As filed pursuant to Rule 424(b)(3)
Registration No. 333-215181

PROXY STATEMENT/PROSPECTUS

MERGER PROPOSED — YOUR VOTE IS IMPORTANT

To the Shareholders of GulfShore Bancshares, Inc.:

On November 3, 2016, Seacoast Banking Corporation of Florida, or Seacoast, Seacoast National Bank, or SNB, GulfShore Bancshares, Inc., or GulfShore, and GulfShore Bank entered into an Agreement and Plan of Merger (which we refer to as the “merger agreement”) that provides for the acquisition of GulfShore by Seacoast. Under the merger agreement, GulfShore will merge with and into Seacoast, with Seacoast as the surviving corporation (which we refer to as the “merger”). Immediately following the merger, GulfShore Bank will merge with and into SNB, with SNB as the surviving bank (which we refer to as the “bank merger”).

In the merger, each share of GulfShore common stock (except for specified shares of GulfShore common stock held by GulfShore or Seacoast and any dissenting shares) will be converted into the right to receive the combination of $1.47 in cash (the “per share cash consideration”) and 0.4807 shares of Seacoast common stock (the “per share stock consideration” and together with the per share cash consideration, the “merger consideration”).

The value of the merger consideration will not be known at the time that GulfShore shareholders vote on the approval of the merger agreement. Based on the closing price of Seacoast’s common stock on the Nasdaq Global Select Market on February 8, 2017, the last practicable date before the date of this document, the value of the merger consideration was approximately $12.29. We urge you to obtain current market quotations for Seacoast (trading symbol “SBCF”) because the value of the per share stock consideration will fluctuate.

Based on the current number of shares of GulfShore common stock outstanding and reserved for issuance under GulfShore employee benefit plans, Seacoast expects to issue approximately 2,784,288 shares of common stock and pay approximately $8.5 million in cash to GulfShore shareholders in the aggregate upon completion of the merger. Based on these numbers, upon completion of the merger, current GulfShore shareholders would own approximately 6.82% of the common stock of Seacoast immediately following the merger. However, any increase or decrease in the number of shares of GulfShore common stock outstanding that occurs for any reason prior to the completion of the merger would cause the actual number of shares issued upon completion of the merger to change.

GulfShore will hold a special meeting of its shareholders in connection with the merger. Holders of GulfShore common stock will be asked to vote to approve the merger agreement and related matters as described in this proxy statement/prospectus. GulfShore shareholders will also be asked to approve the proposal to adjourn the special meeting, if necessary or appropriate, to solicit additional proxies in favor of the merger agreement and related matters, as described in this proxy statement/prospectus.

The special meeting of GulfShore shareholders will be held on Monday, March 27, 2017 at 401 South Florida Avenue, Suite 300, Tampa, Florida 33602, at 10:00 a.m. local time.

GulfShore’s board of directors has determined that the merger agreement and the transactions contemplated thereby, including the merger, are in the best interests of GulfShore and its shareholders, has unanimously approved the merger agreement and recommends that GulfShore shareholders vote “FOR” the proposal to approve the merger agreement and “FOR” the proposal to adjourn the GulfShore special meeting, if necessary or appropriate, to solicit additional proxies in favor of the proposal to approve the merger agreement.

This document, which serves as a proxy statement for the special meeting of GulfShore shareholders and as a prospectus for the shares of Seacoast common stock to be issued in the merger to GulfShore shareholders, describes the special meeting of GulfShore, the merger, the documents related to the merger and other related matters. Please carefully read this entire proxy statement/prospectus, including “ Risk Factors ” beginning on page 20 of this proxy statement/prospectus, for a discussion of the risks relating to the proposed merger. You also can obtain information about Seacoast from documents that Seacoast has filed with the Securities and Exchange Commission.

If you have any questions concerning the merger, GulfShore shareholders should contact Richard Mocsari, Chief Financial Officer of GulfShore at (813) 418-3100. We look forward to seeing you at the meeting.

/s/ Joseph Caballero
Joseph Caballero
President and Chief Executive Officer
GulfShore Bancshares, Inc.

TABLE OF CONTENTS

Neither the Securities and Exchange Commission, the Board of Governors of the Federal Reserve System, the Office of the Comptroller of the Currency, the Federal Deposit Insurance Corporation, nor any state securities commission or any other bank regulatory agency has approved or disapproved the merger, the issuance of the Seacoast common stock to be issued in the merger or the other transactions described in this document or passed upon the adequacy or accuracy of this proxy statement/prospectus. Any representation to the contrary is a criminal offense.

The securities to be issued in the merger are not savings or deposit accounts or other obligations of any bank or non-bank subsidiary of either Seacoast or GulfShore, and they are not insured by the Federal Deposit Insurance Corporation or any other governmental agency.

The date of this proxy statement/prospectus is February 13, 2017, and it is first being mailed or otherwise delivered to the shareholders of GulfShore on or about February 15, 2017.

TABLE OF CONTENTS

NOTICE OF SPECIAL MEETING OF SHAREHOLDERS
TO BE HELD ON MONDAY, MARCH 27, 2017

To the Shareholders of GulfShore Bancshares, Inc.:

GulfShore Bancshares, Inc. (“GulfShore”) will hold a special meeting of shareholders at 10:00 am local time, on Monday, March 27, 2017, at 401 South Florida Avenue, Suite 300, Tampa, Florida 33602, for the following purposes:

We have fixed the close of business on February 10, 2017 as the record date for the GulfShore special meeting. Only holders of record of GulfShore common stock at that time are entitled to notice of, and to vote at, the GulfShore special meeting, or any adjournment or postponement of the GulfShore special meeting. In order for the merger agreement to be approved, at least a majority of the outstanding shares of GulfShore common stock must be voted in favor of the proposal to approve the merger agreement. The special meeting may be adjourned from time to time upon approval of holders of GulfShore common stock without notice other than by announcement at the meeting of the adjournment thereof, and any and all business for which notices are hereby given may be transacted at such adjourned meeting.

GulfShore shareholders have appraisal rights under Florida state law entitling them to obtain payment in cash for the fair value of their shares, provided they comply with each of the requirements under Florida law, including not voting in favor of the merger agreement and providing notice to GulfShore. For more information regarding appraisal rights, please see “ The Merger — Appraisal Rights for GulfShore Shareholders ” beginning on page 50 of this proxy statement/prospectus.

GulfShore shareholders are subject to the Amended and Restated Stockholders’ Agreement, dated as of February 19, 2014, by and among GulfShore and all of its shareholders, which provides for, among other things, the obligation of all GulfShore shareholders to vote for, consent to and raise no objections against, and not otherwise impede or delay, any sale of GulfShore that the GulfShore board of directors and holders representing a majority of the outstanding shares of GulfShore have voted to approve. In the event of the foregoing approval, GulfShore shareholders have also agreed to waive all dissenters rights, appraisal rights and similar rights in connection with such approved sale.

Your vote is important.   We cannot complete the merger unless GulfShore’s shareholders approve the merger agreement.

Regardless of whether you plan to attend the GulfShore special meeting, please vote as soon as possible. If you hold stock in your name as a shareholder of record, please complete, sign, date and

TABLE OF CONTENTS

return the accompanying proxy card in the enclosed postage-paid return envelope as described on the proxy card. If you hold your stock in “street name” through a bank or broker, please follow the instructions on the voting instruction card furnished by the record holder.

The enclosed proxy statement/prospectus provides a detailed description of the special meeting, the merger, the documents related to the merger, including the merger agreement, and other related matters. We urge you to read the proxy statement/prospectus, including any documents incorporated in the proxy statement/prospectus by reference, and its appendices carefully and in their entirety. If you have any questions concerning the merger or the proxy statement/prospectus, would like additional copies of the proxy statement/prospectus or need help voting your shares of GulfShore common stock, please contact Balbina Hyler, Corporate Secretary of GulfShore at (813) 418-3013.

GulfShore’s board of directors has unanimously approved the merger and the merger agreement and recommends that GulfShore shareholders vote “FOR” the proposal to approve the merger agreement and “FOR” the proposal to adjourn the special meeting, if necessary or appropriate, to solicit additional proxies in favor of the proposal to approve the merger agreement.

By Order of the Board of Directors,
/s/ Balbina Hyler
Balbina Hyler
Corporate Secretary

Tampa, Florida
February 13, 2017

TABLE OF CONTENTS

TABLE OF CONTENTS

If you have any questions concerning the merger or this proxy statement/prospectus, would like additional copies of this proxy statement/prospectus or need help voting your shares of GulfShore common stock, please contact Balbina Hyler, Corporate Secretary of GulfShore at (813) 418-3031.

You should rely only on the information contained in, or incorporated by reference into, this proxy statement/prospectus. No one has been authorized to give any information or make any representation about the merger or Seacoast or GulfShore that differs from, or adds to, the information in this proxy statement/prospectus or in documents that are incorporated by reference herein and publicly filed with the SEC. Therefore, if anyone does give you different or additional information, you should not rely on it. You should not assume that the information contained in this proxy statement/prospectus is accurate as of any date other than the date of this proxy statement/prospectus, and you should not assume that any information incorporated by reference into this document is accurate as of any date other than the date of such other document, and neither the mailing of this proxy statement/prospectus to GulfShore shareholders nor the issuance of Seacoast common stock in the merger shall create any implication to the contrary.

This proxy statement/prospectus does not constitute an offer to sell, or a solicitation of an offer to purchase, the securities offered by this proxy statement/prospectus, or the solicitation of a proxy, in any jurisdiction to or from any person to whom or from whom it is unlawful to make such offer, solicitation of an offer or proxy solicitation in such jurisdiction.

TABLE OF CONTENTS

TABLE OF CONTENTS

QUESTIONS AND ANSWERS ABOUT THE MERGER AND THE SPECIAL MEETING			1
SUMMARY			6
Information Regarding Seacoast and GulfShore			6
The Merger			7
Closing and Effective Time of the Merger			7
Merger Consideration			7
Equivalent GulfShore Common Per Share Value			7
Procedures for Converting Shares of GulfShore Common Stock into Merger Consideration			8
Material U.S. Federal Income Tax Consequences of the Merger			8
Appraisal Rights			8
Opinion of GulfShore’s Financial Advisor			9
Treatment of GulfShore Options			9
Interests of GulfShore Directors and Executive Officers in the Merger			9
Regulatory Approvals			10
Conditions to Completion of the Merger			10
Third Party Proposals			11
Termination			11
Termination Fee			12
Nasdaq Listing			12
Accounting Treatment			12
GulfShore Special Meeting			12
Required Shareholder Vote			13
No Restrictions on Resale			13
Market Prices and Dividend Information			13
Comparison of Shareholders’ Rights			14
Risk Factors			15
SEACOAST SELECTED HISTORICAL CONSOLIDATED FINANCIAL DATA			16
MARKET PRICES AND DIVIDEND INFORMATION			18
RISK FACTORS			20
Risks Associated with the Merger			20
Risks Associated with Seacoast’s Business			24
CAUTIONARY STATEMENT ABOUT FORWARD-LOOKING STATEMENTS			25
INFORMATION ABOUT THE GULFSHORE SPECIAL MEETING			26
Time, Date, and Place			26
Matters to be Considered at the Meeting			26
Recommendation of the GulfShore Board of Directors			26
Record Date and Quorum			26
Required Vote			26
How to Vote — Shareholders of Record			27

TABLE OF CONTENTS

How to Vote — Shares Held in “Street Name”			27
Revocation of Proxies			28
Shares Subject to Voting and Joinder Agreements; Shares Held by Directors			28
Solicitation of Proxies			29
Attending the Meeting			29
Questions and Additional Information			29
THE MERGER			30
Background of the Merger			30
GulfShore’s Reasons for the Merger and Recommendation of the GulfShore Board of Directors			33
Seacoast’s Reasons for the Merger			35
Opinion of GulfShore’s Financial Advisor			36
Certain Unaudited Prospective Financial Information of GulfShore			46
Material U.S. Federal Income Tax Consequences of the Merger			47
Accounting Treatment			50
Regulatory Approvals			50
Appraisal Rights for GulfShore Shareholders			50
Board of Directors and Management of Seacoast Following the Merger			51
Interests of GulfShore Directors and Executive Officers in the Merger			51
THE MERGER AGREEMENT			54
The Merger and the Bank Merger			54
Closing and Effective Time of the Merger			54
Merger Consideration			54
Procedures for Converting Shares of GulfShore Common Stock into Merger Consideration			55
Exchange Agent			55
Transmittal Materials and Procedures			55
Treatment of GulfShore Options			56
Conduct of Business Pending the Merger			56
Regulatory Matters			59
Nasdaq Listing			59
Employee Matters			59
Indemnification and Directors’ and Officers’ Insurance			60
Third Party Proposals			60
GulfShore Board Recommendation			61
Representations and Warranties			62
Conditions to Completion of the Merger			64
Termination			65
Termination Fee			66
Release			66
Amendment; Waiver			67
Expenses			67

TABLE OF CONTENTS

COMPARISON OF SHAREHOLDERS’ RIGHTS			68
BUSINESS OF GULFSHORE BANCSHARES, INC.			79
BENEFICIAL OWNERSHIP OF GULFSHORE COMMON STOCK BY MANAGEMENT AND PRINCIPAL SHAREHOLDERS OF GULFSHORE			82
DESCRIPTION OF SEACOAST CAPITAL STOCK			84
Common Stock			84
General			84
Voting Rights			84
Registration Rights			84
Dividends, Liquidation and Other Rights			84
Restrictions on Ownership			84
Preferred Stock			85
General			85
Transfer Agent and Registrar			85
Anti-Takeover Effects of Certain Articles of Incorporation Provisions			85
EXPERTS			88
LEGAL MATTERS			88
OTHER MATTERS			88
DOCUMENTS INCORPORATED BY REFERENCE			88
APPENDICES:
Appendix A — Agreement and Plan of Merger			A-1
Appendix B — Opinion of Sandler O’Neill & Partners, L.P.			B-1
Appendix C — Provisions of Florida Business Corporation Act Relating to Appraisal Rights			C-1

TABLE OF CONTENTS

TABLE OF CONTENTS

TABLE OF CONTENTS

TABLE OF CONTENTS

For further information, see “ The Merger — Material U.S. Federal Income Tax Consequences of the Merger” beginning on page 47 of this proxy statement/prospectus.

The U.S. federal income tax consequences described above may not apply to all holders of GulfShore common stock. Your tax consequences will depend on your individual situation. Accordingly, we strongly urge you to consult your own tax advisor to determine the particular tax consequences of the merger to you.

TABLE OF CONTENTS

Important Notice Regarding the Availability of Proxy Materials for the Special
Shareholder Meeting to be Held on Monday, March 27, 2017.

TABLE OF CONTENTS

TABLE OF CONTENTS

The Merger (see page 30 )

The terms and conditions of the merger are contained in the merger agreement, a copy of which is included as Appendix A to this proxy statement/prospectus and is incorporated by reference herein. You should read the merger agreement carefully and in its entirety, as it is the legal document governing the merger.

In the merger, GulfShore will merge with and into Seacoast, with Seacoast as the surviving company in the merger. Immediately following the merger of GulfShore into Seacoast, GulfShore Bank will merge with and into SNB, with SNB as the surviving bank of such bank merger.

Closing and Effective Time of the Merger (see page 54 )

The closing date is currently expected to occur in the second quarter of 2017. Simultaneously with the closing of the merger, Seacoast will file the articles of merger with the Secretary of State of the State of Florida. The merger will become effective at such time as the articles of merger are filed or such other time as may be specified in the articles of merger. Neither Seacoast nor GulfShore can predict, however, the actual date on which the merger will be completed because it is subject to factors beyond each company’s control, including whether or when the required regulatory approvals and GulfShore’s shareholder approval will be received.

Merger Consideration (see page 54 )

Each issued and outstanding share of GulfShore common stock, other than excluded shares and dissenting shares, will be converted into the right to receive the merger consideration, which is the combination of $1.47 in cash and 0.4807 of a share of Seacoast common stock. No holder of GulfShore common stock will be issued fractional shares of Seacoast common stock in the merger. Each holder of GulfShore common stock who would otherwise have been entitled to receive a fraction of a share of Seacoast common stock will receive, in lieu thereof, cash, without interest, in an amount equal to such fractional part of a share of Seacoast common stock multiplied by the average daily volume weighted average price of Seacoast common stock on the Nasdaq Global Select Market for the ten trading days preceding the closing date. See “ The Merger Agreement — Merger Consideration ” beginning on page 54 of this proxy statement/prospectus.

The value of the shares of Seacoast common stock to be issued in the merger will fluctuate between now and the closing date of the merger. Based on the closing price of Seacoast common stock on November 3, 2016, the date of the signing of the merger agreement, the value of the per share merger consideration payable to holders of GulfShore common stock was approximately $9.76. Based on the closing price of Seacoast common stock on February 8, 2017, the last practicable date before the date of this document, the value of the per share merger consideration payable to holders of GulfShore common stock was approximately $12.29. GulfShore shareholders should obtain current sale prices for Seacoast common stock, which is traded on the Nasdaq Global Select Market under the symbol “SBCF.”

Equivalent GulfShore Common Per Share Value

Seacoast common stock trades on the Nasdaq Global Select Market under the symbol “SBCF.” The GulfShore common stock is not listed or traded on any established securities exchange or quotation system. Accordingly, there is no established public trading market for the GulfShore common stock. The following table presents the closing price of Seacoast common stock on November 3, 2016, the last trading date prior to the public announcement of the merger agreement, and February 8, 2017, the last practicable trading day prior to the printing of this proxy statement/prospectus. The table also presents the equivalent value of the merger consideration per share of GulfShore common stock on those dates, calculated by multiplying the closing sales price of Seacoast common stock on those dates by the exchange ratio of 0.4807 and adding $1.47 to such amount.

Date		Seacoast closing sale price				Equivalent GulfShore per share value
November 3, 2016		$	17.24			$	9.76
February 8, 2017		$	22.50			$	12.29

TABLE OF CONTENTS

The value of the shares of Seacoast common stock to be issued in the merger will fluctuate between now and the closing date of the merger. If Seacoast shares increase in value, so will the value of the per share merger consideration. Similarly, if Seacoast shares decline in value, so will the value of the consideration to be received by GulfShore shareholders. GulfShore shareholders should obtain current sale prices for the Seacoast common stock.

Procedures for Converting Shares of GulfShore Common Stock into Merger Consideration (see page 55 )

Promptly after the effective time of the merger, Seacoast’s exchange agent, Continental Stock Transfer and Trust Company, will mail to each holder of record of GulfShore common stock that is converted into the right to receive the merger consideration a letter of transmittal and instructions for the surrender of the holder’s GulfShore stock certificate(s) for the merger consideration (including cash in lieu of any fractional Seacoast shares), and any dividends or distributions to which such holder is entitled to pursuant to the merger agreement.

Please do not send in your certificates until you receive these instructions.

Material U.S. Federal Income Tax Consequences of the Merger (see page 47 )

The merger is intended to qualify as a “reorganization” within the meaning of Section 368(a) of the Code, and it is a condition to the respective obligations of GulfShore and Seacoast to complete the merger that each of GulfShore and Seacoast receives a legal opinion to that effect. If, as expected, the merger qualifies as a “reorganization”, a U.S. holder (as defined in “The Merger — Material U.S. Federal Income Tax Consequences of the Merger” beginning on page 47 of this proxy statement/prospectus) of GulfShore common stock will generally recognize gain (but not loss) in an amount equal to the lesser of: (1) the amount of cash treated as received in exchange for GulfShore common stock in the merger (excluding any cash received in lieu of fractional shares of Seacoast common stock) and (2) the excess, if any, of (a) the sum of the amount of cash treated as received in exchange for GulfShore common stock in the merger (excluding any cash received in lieu of fractional shares of Seacoast common stock) plus the fair market value of Seacoast common stock (including the fair market value of any Seacoast fractional shares treated as received in the merger) over (b) such U.S. holder’s basis in the GulfShore common stock exchanged.

For further information, see “ The Merger — Material U.S. Federal Income Tax Consequences of the Merger” beginning on page 47 of this proxy statement/prospectus.

The U.S. federal income tax consequences described above may not apply to all holders of GulfShore common stock. Your tax consequences will depend on your individual situation. Accordingly, we strongly urge you to consult your own tax advisor to determine the particular tax consequences of the merger to you.

Appraisal Rights (see page 50 and Appendix C)

Under Florida law, GulfShore shareholders have the right to dissent from the merger and receive a cash payment equal to the fair value of their shares of GulfShore stock instead of receiving the merger consideration. To exercise appraisal rights, GulfShore shareholders must strictly follow the procedures established by Sections 607.1301 through 607.1333 of the Florida Business Corporation Act, or the FBCA, which include filing a written objection with GulfShore prior to the special meeting stating, among other things, that the shareholder will exercise his or her right to dissent if the merger is completed, and not voting for approval of the merger agreement. A shareholder’s failure to vote against the merger agreement will not constitute a waiver of such shareholder’s dissenters’ rights. However, all GulfShore shareholders are subject to that certain Amended and Restated Stockholders’ Agreement, dated as of February 19, 2014, which provides for, among other things, the obligation of all GulfShore shareholders to vote for, consent to and raise no objections against, and not otherwise impede or delay, any sale of GulfShore that holders representing a majority of the outstanding shares of GulfShore have voted to approve. In the event of the foregoing approval, GulfShore shareholders have also agreed to waive all dissenters rights, appraisal rights and similar rights in connection with such approved sale. Therefore, if the merger agreement is approved, GulfShore shareholders will be required to waive their statutory appraisal rights.

TABLE OF CONTENTS

Opinion of GulfShore’s Financial Advisor (see page 36 and Appendix B)

GulfShore’s financial advisor in connection with the merger, Sandler O’Neill & Partners, L.P. (“Sandler O’Neill”), has delivered a written opinion, dated November 2, 2016, to the board of directors of GulfShore to the effect that, as of the date of the opinion, based upon and subject to certain matters stated in the opinion, the merger consideration was fair to the holders of GulfShore common stock from a financial point of view. We have attached this opinion to this proxy statement/prospectus as Appendix B. The opinion of Sandler O’Neill is not a recommendation to any GulfShore shareholder as to how to vote on the proposal to approve the merger agreement.

For further information, including with respect to the procedures followed, matters considered and limitations and qualifications on the review undertaken by Sandler O’Neill in providing its opinion, please see the section entitled “ The Merger — Opinion of GulfShore’s Financial Advisor ” beginning on page 36 of this proxy statement/prospectus.

Treatment of GulfShore Options (see page 56 )

Each outstanding option to purchase GulfShore common stock granted under a GulfShore benefit plan shall vest in full to the extent unvested and be cancelled and converted into the right to receive a cash payment equal to the option award consideration.

Recommendation of the GulfShore Board of Directors (see page 26 )

After careful consideration, the GulfShore board of directors unanimously recommends that GulfShore shareholders vote “ FOR ” the approval of the merger agreement and the approval of the adjournment proposal described in this document. Each of the directors of GulfShore has entered into a voting and joinder agreement with Seacoast pursuant to which each has agreed to vote “ FOR ” the approval of the merger agreement and any other matter required to be approved by the shareholders of GulfShore to facilitate the transactions contemplated by the merger agreement, subject to the terms of the voting and joinder agreements.

For more information regarding the voting and joinder agreements, please see the section entitled “ Information About the GulfShore Special Meeting — Shares Subject to Voting and Joinder Agreements; Shares Held by Directors and Executive Officers ” on page 28 of this proxy statement/prospectus.

For a more complete description of GulfShore’s reasons for the merger and the recommendations of the GulfShore board of directors, please see the section entitled “ The Merger — GulfShore’s Reasons for the Merger and Recommendation of the GulfShore Board of Directors ” beginning on page 33 of this proxy statement/prospectus.

Interests of GulfShore Directors and Executive Officers in the Merger (see page 51 )

In the merger, the directors and executive officers of GulfShore will receive the same merger consideration for their GulfShore shares as the other GulfShore shareholders. In considering the recommendation of the GulfShore board of directors that you vote to approve the merger agreement, you should be aware that some of the executive officers and directors of GulfShore may have interests in the merger and may have arrangements that may be considered to be different from, or in addition to, those of GulfShore shareholders generally. Interests of officers and directors that may be different from or in addition to the interests of GulfShore’s shareholders include:

TABLE OF CONTENTS

These interests are discussed in more detail in the section entitled “ The Merger — Interests of GulfShore Directors and Executive Officers in the Merger ” beginning on page 51 of this proxy statement/prospectus. The GulfShore board of directors was aware of these interests and considered them, along with other matters, in reaching its decision to adopt and approve the merger agreement and to recommend that GulfShore shareholders vote in favor of approving the merger agreement.

Regulatory Approvals (see page 50 )

Completion of the merger and the bank merger are subject to various regulatory approvals, including approvals from the Federal Reserve and the OCC. Notifications and/or applications requesting approvals for the merger or for the bank merger may also be submitted to other federal and state regulatory authorities and self-regulatory organizations. The parties have filed notices and applications to obtain the necessary regulatory approvals of the Federal Reserve and the OCC. The parties cannot be certain when or if they will obtain all of the regulatory approvals or, if obtained, whether they will contain terms, conditions or restrictions not currently contemplated that will be detrimental to or have a material adverse effect on the combined company after the completion of the merger. The regulatory approvals to which the completion of the merger and bank merger are subject are described in more detail under the section entitled “ The Merger — Regulatory Approvals ,” beginning on page 50 of this proxy statement/prospectus.

Conditions to Completion of the Merger (see page 64 )

The completion of the merger depends on a number of conditions being satisfied or, where permitted, waived, including but not limited to:

TABLE OF CONTENTS

No assurance is given as to when, or if, the conditions to the merger will be satisfied or waived, or that the merger will be completed.

Third Party Proposals (see page 60 )

GulfShore has agreed to a number of limitations with respect to soliciting, negotiating and discussing acquisition proposals involving persons other than Seacoast, and to certain related matters. The merger agreement does not, however, prohibit GulfShore from considering a bona fide unsolicited written acquisition proposal from a third party if certain specified conditions are met.

Termination (see page 65 )

The merger agreement may be terminated at any time prior to the effective time of the merger:

TABLE OF CONTENTS

Termination Fee (see page 66 )

GulfShore will owe Seacoast a termination fee of $2,125,000 if:

The payment of the termination fee will fully discharge GulfShore from any losses that may be suffered by Seacoast arising out of the termination of the merger agreement.

Nasdaq Listing (see page 59 )

Seacoast will cause the shares of Seacoast common stock to be issued to the holders of GulfShore common stock in the merger to be authorized for listing on the Nasdaq Global Select Market, subject to official notice of issuance, prior to the effective time of the merger.

Accounting Treatment (see page 50 )

Seacoast will account for the merger under the acquisition method of accounting for business combinations under accounting principles generally accepted in the United States of America.

GulfShore Special Meeting (see page 26 )

The special meeting of GulfShore shareholders will be held on Monday, March 27, 2017, at 10:00 a.m., local time, at 401 South Florida Avenue, Suite 300, Tampa, Florida 33602. At the special meeting, GulfShore shareholders will be asked to vote on:

Holders of GulfShore common stock as of the close of business on February 10, 2017, the record date, will be entitled to vote at the special meeting. As of the record date, there were outstanding and entitled to

TABLE OF CONTENTS

notice and to vote an aggregate of 5,464,308 shares of GulfShore common stock held by approximately 166 shareholders of record. Each GulfShore shareholder can cast one vote for each share of GulfShore common stock owned on the record date.

As of the record date, directors of GulfShore, their affiliates, and certain executive officers owned and were entitled to vote 3,511,475 shares of GulfShore common stock, representing approximately 64.26% of the outstanding shares of GulfShore common stock entitled to vote on that date. Pursuant to his, her or its respective voting and joinder agreement, each such person or entity has agreed at any meeting of GulfShore shareholders, however called, or any adjournment or postponement thereof (and subject to certain exceptions) to vote the shares owned in favor of the merger agreement and the adjournment proposal. However, if the GulfShore board of directors makes a company subsequent determination, only 46.63% of the shares owned by a shareholder who is party to a voting and joinder agreement (approximately 29.5% of the outstanding shares of GulfShore common stock entitled to vote at the special meeting) will be required to be voted in favor of the merger agreement and adjournment proposal. As of the record date, Seacoast did not own or have the right to vote any of the outstanding shares of GulfShore common stock.

Required Shareholder Vote (see page 26 )

In order to approve the merger agreement, the holders of a majority of the outstanding shares of GulfShore common stock, as of the record date, must vote in favor of the merger agreement.

No Restrictions on Resale

All shares of Seacoast common stock received by GulfShore shareholders in the merger will be freely tradable, except that shares of Seacoast received by persons who are or become affiliates of Seacoast for purposes of Rule 144 under the Securities Act may be resold by them only in transactions permitted by Rule 144, or as otherwise permitted under the Securities Act.

Market Prices and Dividend Information (see page 18 )

Seacoast common stock is listed and trades on the Nasdaq Global Select Market under the symbol “SBCF.” As of February 8, 2017, there were 38,020,113 shares of Seacoast common stock outstanding. Approximately 54.14% of these shares are owned by institutional investors, as reported by Nasdaq. Seacoast’s top three institutional investors own approximately 32.91% of its outstanding stock. Seacoast has approximately 2,220 shareholders of record.

To Seacoast’s knowledge, the only shareholders who owned more than 5% of the outstanding shares of Seacoast common stock on January 31, 2017 were: CapGen Capital Group III LP (19.63%), 120 West 45 ^th Street, Suite 1010, New York, New York 10036; BlackRock Institutional Trust Company, NA (7.08%), 55 East 52 ^nd Street, New York, New York 10055; and Basswood Capital Management, LLC (6.19%), 645 Madison Avenue, 10 ^th Floor, New York, New York 10022.

GulfShore common stock is not listed or traded on any established securities exchange or quotation system. Accordingly, there is no established public trading market for the GulfShore common stock. Transactions in the shares are privately negotiated directly between the purchaser and the seller and sales, if they do occur, are not subject to any reporting system. The shares of GulfShore are not traded frequently and are subject to transfer restrictions under the GulfShore Amended and Restated Stockholders’ Agreement, dated as of February 19, 2014, by and among GulfShore Bancshares, Inc. and all of the shareholders of GulfShore. As of February 10, 2017, there were 5,464,308 shares of GulfShore common stock outstanding held by approximately 166 shareholders of record.

TABLE OF CONTENTS

The following tables show, for the indicated periods, the high and low sales prices per share for Seacoast common stock, as reported on Nasdaq. Seacoast did not pay cash dividends on its common stock during the periods indicated.

		Seacoast Common Stock
		High				Low				Dividends
2017
First Quarter (through February 8, 2017)		$	22.65			$	20.83			$	0.00
2016
First Quarter		$	16.22			$	13.40			$	0.00
Second Quarter		$	17.19			$	15.21			$	0.00
Third Quarter		$	17.80			$	15.50			$	0.00
Fourth Quarter		$	22.90			$	16.02			$	0.00
2015
First Quarter		$	14.46			$	12.02			$	0.00
Second Quarter		$	16.09			$	13.81			$	0.00
Third Quarter		$	16.26			$	14.11			$	0.00
Fourth Quarter		$	16.95			$	14.10			$	0.00
2014
First Quarter		$	12.51			$	10.55			$	0.00
Second Quarter		$	11.28			$	10.00			$	0.00
Third Quarter		$	11.27			$	10.03			$	0.00
Fourth Quarter		$	14.24			$	10.80			$	0.00
2013
First Quarter		$	11.25			$	7.75			$	0.00
Second Quarter		$	11.00			$	8.50			$	0.00
Third Quarter		$	12.30			$	10.10			$	0.00
Fourth Quarter		$	12.49			$	10.10			$	0.00

Dividends from SNB are Seacoast’s primary source of funds to pay dividends on its common stock. Under the National Bank Act, national banks may in any calendar year, without the approval of the OCC, pay dividends to the extent of net profits for that year, plus retained net profits for the preceding two years (less any required transfers to surplus). The need to maintain adequate capital in SNB also limits dividends that may be paid to Seacoast. Beginning in the third quarter of 2008, Seacoast reduced its dividend per share of common stock to a de minimis $0.01. On May 19, 2009, Seacoast’s board of directors voted to suspend quarterly dividends on its common stock entirely.

Any dividends paid on Seacoast’s common stock would be declared and paid at the discretion of its board of directors and would be dependent upon Seacoast’s liquidity, financial condition, results of operations, capital requirements and such other factors as the board of directors may deem relevant.

GulfShore does not pay quarterly dividends to its common shareholders.

Comparison of Shareholders’ Rights (see page 68 )

The rights of GulfShore shareholders who continue as Seacoast shareholders after the merger will be governed by the articles of incorporation and bylaws of Seacoast rather than the articles of incorporation and bylaws of GulfShore. For more information, please see the section entitled “ Comparison of Shareholders’ Rights ” beginning on page 68 of this proxy statement/prospectus.

TABLE OF CONTENTS

Risk Factors (see page 20 )

Before voting at the GulfShore special meeting, you should carefully consider all of the information contained or incorporated by reference into this proxy statement/prospectus, including the risk factors set forth in the section entitled “ Risk Factors ” beginning on page 20 of this proxy statement/prospectus or described in Seacoast’s reports filed with the SEC, which are incorporated by reference into this proxy statement/prospectus. Please see the section entitled “ Documents Incorporated by Reference ” beginning on page 88 of this proxy statement/prospectus.

TABLE OF CONTENTS

SEACOAST SELECTED HISTORICAL CONSOLIDATED FINANCIAL DATA

The following selected historical consolidated financial data as of and for the twelve months ended December 31, 2015, 2014, 2013, 2012 and 2011 is derived from the audited consolidated financial statements of Seacoast.

The following selected historical consolidated financial data as of and for the nine months ended September 30, 2016 and 2015 is derived from the unaudited consolidated financial statements of Seacoast and has been prepared on the same basis as the selected historical consolidated financial data derived from the audited consolidated financial statements and, in the opinion of Seacoast’s management, reflects all adjustments, consisting only of normal recurring adjustments, necessary for a fair presentation of this data for those dates.

The results of operations as of and for the nine months ended September 30, 2016 are not necessarily indicative of the results that may be expected for the twelve months ending December 31, 2016 or any future period. You should read the following selected historical consolidated financial data in conjunction with: (i) the section entitled “Management’s Discussion and Analysis of Financial Condition and Results of Operations” and Seacoast’s audited consolidated financial statements and accompanying notes included in Seacoast’s Annual Report on Form 10-K for the twelve months ended December 31, 2015; and (ii) the section entitled “Management’s Discussion and Analysis of Financial Condition and Results of Operations” and Seacoast’s unaudited consolidated financial statements and accompanying notes included in Seacoast’s Quarterly Report on Form 10-Q for the nine months ended September 30, 2016, both of which are incorporated by reference into this proxy statement/prospectus. See “ Documents Incorporated by Reference ” beginning on page 88 of this proxy statement/prospectus.

		Nine months ended September 30,								Year ended December 31,
		2016				2015				2015				2014				2013				2012				2011
Net interest income		$	102,163			$	80,387			$	109,487			$	74,907			$	65,206			$	64,809			$	66,839
Provision for loan losses			1,411				2,275				2,644				(3,486	)			3,188				10,796				1,974
Noninterest income:
Other			27,505				24,236				32,018				24,744				24,319				21,444				18,345
Bargain purchase gain			—				—				416				—				—								—
Loss on sale of loan			—				—				—				—				—				(1,238	)			—
Securities gains, net			361				160				161				469				419				7,619				1,220
Noninterest expenses			100,584				76,601				103,770				93,366				75,152				82,548				77,763
Income (loss) before income taxes			28,034				25,907				35,668				10,240				11,604				(710	)			6,667
Provision (benefit) for income taxes			9,603				9,802				13,527				4,544				(40,385	)			—				—
Net income (loss)		$	18,431			$	16,105			$	22,141			$	5,696			$	51,989			$	(710	)		$	6,667
Per Share Data
Net income (loss) available to common shareholders:
Diluted		$	0.49			$	0.48			$	0.66			$	0.21			$	2.44			$	(0.24	)		$	0.16
Basic			0.50				0.48				0.66				0.21				2.46				(0.24	)			0.16
Cash dividends declared			0				0				0				0				0				0				0
Book value per share common			11.45				10.20				10.29				9.44				8.40				6.16				6.46
Assets			4,513,934				3,378,108				3,534,780				3,093,335				2,268,940				2,173,929				2,137,375
Securities			1,258,751				937,208				994,291				949,279				641,611				656,868				668,339
Net loans			2,746,654				2,080,119				2,137,202				1,804,814				1,284,139				1,203,977				1,182,509
Deposits			3,510,493				2,742,296				2,844,387				2,416,534				1,806,045				1,758,961				1,718,741
Shareholders’ equity			435,519				350,280				353,453				312,651				198,604				165,546				170,077

TABLE OF CONTENTS

		Nine months ended September 30,								Year ended December 31,
		2016				2015				2015				2014				2013				2012				2011
Performance ratios:
Return on average assets			0.60	%			0.66	%			0.67	%			0.23	%			2.38	%			(0.03	)%			0.32	%
Return on average equity			6.06				6.49				6.56				2.22				28.36				(0.43	)			4.03
Net interest margin (1)			3.67				3.62				3.64				3.25				3.15				3.22				3.42
Average equity to average assets			9.96				10.21				10.22				10.34				8.38				7.81				8.01

TABLE OF CONTENTS

MARKET PRICES AND DIVIDEND INFORMATION

Seacoast common stock is listed and trades on the Nasdaq Global Select Market under the symbol “SBCF.” As of February 8, 2017, there were 38,020,113 shares of Seacoast common stock outstanding. Approximately 54.14% of these shares are owned by institutional investors, as reported by Nasdaq. Seacoast’s top three institutional investors own approximately 32.91% of its outstanding stock. Seacoast has approximately 2,220 shareholders of record.

To Seacoast’s knowledge, the only shareholders who owned more than 5% of the outstanding shares of Seacoast common stock on February 8, 2017 were: CapGen Capital Group III LP (19.63%), 120 West 45 ^th Street, Suite 1010, New York, New York 10036; BlackRock Institutional Trust Company, NA (7.08%), 55 East 52 ^nd Street, New York, New York 10055; and Basswood Capital Management, LLC (6.19%), 645 Madison Avenue, 10 ^th Floor, New York, New York 10022.

GulfShore common stock is not listed or traded on any established securities exchange or quotation system. Accordingly, there is no established public trading market for the GulfShore common stock. Transactions in the shares are privately negotiated directly between the purchaser and the seller and sales, if they do occur, are not subject to any reporting system. The shares of GulfShore are not traded frequently and are subject to transfer restrictions under the GulfShore Amended and Restated Stockholders’ Agreement, dated as of February 19, 2014, by and among GulfShore Bancshares, Inc. and all of the shareholders of GulfShore. As of February 10, 2017, there were 5,464,308 shares of GulfShore common stock outstanding, which were held by 166 holders of record.

The following tables show, for the indicated periods, the high and low sales prices per share for Seacoast common stock, as reported on Nasdaq. Cash dividends declared and paid per share on Seacoast common stock are also shown for the periods indicated below. Seacoast did not pay cash dividends on its common stock during the periods indicated.

The high and low sales prices reflect inter-dealer prices, without retail mark-up, mark-down or commission, and may not necessarily represent actual transactions.

		Seacoast Common Stock
		High				Low				Dividend
2014
First Quarter		$	12.51			$	10.55			$	—
Second Quarter		$	11.28			$	10.00			$	—
Third Quarter		$	11.27			$	10.03			$	—
Fourth Quarter		$	14.24			$	10.80			$	—
2015
First Quarter		$	14.46			$	12.02			$	—
Second Quarter		$	16.09			$	13.81			$	—
Third Quarter		$	16.26			$	14.11			$	—
Fourth Quarter		$	16.95			$	14.10			$	—
2016
First Quarter		$	16.22			$	13.40			$	—
Second Quarter		$	17.19			$	15.21			$	—
Third Quarter		$	17.80			$	15.50			$	—
Fourth Quarter		$	22.90			$	16.02			$	—
2017
First Quarter (through February 8, 2017)		$	22.65			$	20.83			$	—

TABLE OF CONTENTS

Dividends from SNB are Seacoast’s primary source of funds to pay dividends on its common stock. Under the National Bank Act, national banks may in any calendar year, without the approval of the OCC, pay dividends to the extent of net profits for that year, plus retained net profits for the preceding two years (less any required transfers to surplus). The need to maintain adequate capital in SNB also limits dividends that may be paid to Seacoast. Beginning in the third quarter of 2008, Seacoast reduced its dividend per share of common stock to a de minimis $0.01. On May 19, 2009, Seacoast’s board of directors voted to suspend quarterly dividends on its common stock entirely.

Any dividends paid on Seacoast’s common stock would be declared and paid at the discretion of its board of directors and would be dependent upon Seacoast’s liquidity, financial condition, results of operations, capital requirements and such other factors as the board of directors may deem relevant.

GulfShore does not pay dividends to its common shareholders.

TABLE OF CONTENTS

TABLE OF CONTENTS

of GulfShore. It is currently expected that the former shareholders of GulfShore as a group will receive shares in the merger constituting approximately 6.82% of the outstanding shares of the combined company’s common stock immediately after the merger. Because of this, GulfShore shareholders who receive shares of Seacoast common stock in the merger will have less influence on the management and policies of the combined company than they now have on the management and policies of GulfShore.

Seacoast and GulfShore will be subject to business uncertainties and contractual restrictions while the merger is pending.

Uncertainty about the effect of the merger on employees, customers, suppliers and vendors may have an adverse effect on the business, financial condition and results of operations of GulfShore and Seacoast. These uncertainties may impair Seacoast’s or GulfShore’s ability to attract, retain and motivate key personnel, depositors and borrowers pending the consummation of the merger, as such personnel, depositors and borrowers may experience uncertainty about their future roles following the consummation of the merger. Additionally, these uncertainties could cause customers (including depositors and borrowers), suppliers, vendors and others who deal with Seacoast or GulfShore to seek to change existing business relationships with Seacoast or GulfShore or fail to extend an existing relationship. In addition, competitors may target each party’s existing customers by highlighting potential uncertainties and integration difficulties that may result from the merger.

Seacoast and GulfShore have a small number of key personnel. The pursuit of the merger and the preparation for the integration in connection therewith may place a burden on each company’s management and internal resources. Any significant diversion of management attention away from ongoing business concerns and any difficulties encountered in the transition and integration process could have a material adverse effect on each company’s business, financial condition and results of operations.

In addition, the merger agreement restricts GulfShore from taking certain actions without Seacoast’s consent while the merger is pending. These restrictions may, among other matters, prevent GulfShore from pursuing otherwise attractive business opportunities, selling assets, incurring indebtedness, engaging in significant capital expenditures in excess of certain limits set forth in the merger agreement, entering into other transactions or making other changes to GulfShore’s business prior to consummation of the merger or termination of the merger agreement. These restrictions could have a material adverse effect on GulfShore’s business, financial condition and results of operations. Please see the section entitled “ The Merger Agreement — Conduct of Business Pending the Merger ” beginning on page 56 of this proxy statement/prospectus for a description of the covenants applicable to GulfShore and Seacoast.

Seacoast may fail to realize the cost savings estimated for the merger.

Although Seacoast estimates that it will realize cost savings from the merger when fully phased in, it is possible that the estimates of the potential cost savings could turn out to be incorrect. For example, the combined purchasing power may not be as strong as expected, and therefore the cost savings could be reduced. In addition, unanticipated growth in Seacoast’s business may require Seacoast to continue to operate or maintain some facilities or support functions that are currently expected to be combined or reduced. The cost savings estimates also depend on Seacoast’s ability to combine the businesses of Seacoast and GulfShore in a manner that permits those costs savings to be realized. If the estimates turn out to be incorrect or Seacoast is not able to combine the two companies successfully, the anticipated cost savings may not be fully realized or realized at all, or may take longer to realize than expected.

The combined company expects to incur substantial expenses related to the merger.

The combined company expects to incur substantial expenses in connection with completing the merger and combining the business, operations, networks, systems, technologies, policies and procedures of Seacoast and GulfShore. Although Seacoast and GulfShore have assumed that a certain level of transaction and combination expenses would be incurred, there are a number of factors beyond their control that could affect the total amount or the timing of these expenses. Many of the expenses that will be incurred, by their nature, are difficult to estimate accurately at the present time. Due to these factors, the transaction and combination expenses associated with the merger could, particularly in the near term, exceed the savings that the combined

TABLE OF CONTENTS

company expects to achieve from the elimination of duplicative expenses and the realization of economies of scale and cost savings related to the combination of the businesses following the completion of the merger. In addition, prior to completion of the merger, each of GulfShore and Seacoast will incur or have incurred substantial expenses in connection with the negotiation and completion of the transactions contemplated by the merger agreement. If the merger is not completed, Seacoast and GulfShore would have to recognize these expenses without realizing the anticipated benefits of the merger.

Seacoast and GulfShore may waive one or more of the conditions to the merger without re-soliciting GulfShore shareholder approval for the merger agreement.

Each of the conditions to the obligations of Seacoast and GulfShore to complete the merger may be waived, in whole or in part, to the extent permitted by applicable law, by agreement of Seacoast and GulfShore, if the condition is a condition to both parties’ obligation to complete the merger, or by the party for which such condition is a condition of its obligation to complete the merger. The boards of directors of Seacoast and GulfShore may evaluate the materiality of any such waiver to determine whether amendment of this proxy statement/prospectus and re-solicitation of proxies is necessary. Seacoast and GulfShore, however, generally do not expect any such waiver to be significant enough to require re-solicitation of GulfShore’s shareholders. In the event that any such waiver is not determined to be significant enough to require re-solicitation of GulfShore’s shareholders, the companies will have the discretion to complete the merger without seeking further shareholder approval.

If the merger fails to qualify as a “reorganization” within the meaning of Section 368(a) of the Code, GulfShore shareholders may be required to recognize additional gain or recognize loss on the exchange of their shares of GulfShore common stock in the merger for U.S. federal income tax purposes.

The merger is intended to qualify as a “reorganization” within the meaning of Section 368(a) of the Code, and it is a condition to the respective obligations of GulfShore and Seacoast to complete the merger that each of GulfShore and Seacoast receives a legal opinion to that effect. None of these opinions will be binding on the Internal Revenue Service. GulfShore and Seacoast have not sought and will not seek any ruling from the Internal Revenue Service regarding any matters relating to the merger, and as a result, there can be no assurance that the Internal Revenue Service will not assert, or that a court would not sustain, a position contrary to any of the conclusions set forth herein. If the merger fails to qualify as a “reorganization” within the meaning of Section 368(a) of the Code, GulfShore shareholders may be required to recognize additional gain or recognize loss on the exchange of their shares of GulfShore common stock in the merger for U.S. federal income tax purposes. For further information, see “ The Merger — Material U.S. Federal Income Tax Consequences of the Merger” beginning on page 47 of this proxy statement/prospectus.

Regulatory approvals may not be received, may take longer than expected or impose conditions that are not presently anticipated.

Before the transactions contemplated by the merger agreement, including the merger and the bank merger, may be completed, various approvals must be obtained from bank regulatory authorities. These governmental entities may impose conditions on the granting of such approvals. Such conditions or changes and the process of obtaining regulatory approvals could have the effect of delaying completion of the merger or of imposing additional costs or limitations on Seacoast following the merger. The regulatory approvals may not be received at all, may not be received in a timely fashion, and may contain conditions on the completion of the merger that are not anticipated or have a material adverse effect. If the consummation of the merger is delayed, including by a delay in receipt of necessary governmental approvals, the business, financial condition and results of operations of each company may also be materially adversely affected.

The fairness opinion of GulfShore’s financial advisor will not reflect changes in circumstances between the date of the opinion and the completion of the merger.

GulfShore’s board of directors received an opinion from its financial advisor to address the fairness of the consideration to be received by the holders of GulfShore common stock pursuant to the merger agreement from a financial point of view as of the date of such opinion. Subsequent changes in the operation and prospects of Seacoast or GulfShore, general market and economic conditions and other factors that may be

TABLE OF CONTENTS

beyond the control of Seacoast or GulfShore, may significantly alter the value of Seacoast or the price of the shares of Seacoast common stock by the time the merger is completed. Because GulfShore does not anticipate asking its financial advisor to update its opinion, the opinion will not address the fairness of the merger consideration from a financial point of view at the time the merger is completed, or as of any other date other than the date of such opinion. For a description of the opinion that GulfShore’s board received from its financial advisor, please refer to the section entitled “ The Merger — Opinion of GulfShore’s Financial Advisor ” beginning on page 36 of this proxy statement/prospectus.

GulfShore’s executive officers and directors have financial interests in the merger that are different from, or in addition to, the interests of GulfShore shareholders generally.

Executive officers of GulfShore negotiated the terms of the merger agreement with Seacoast, and the GulfShore board of directors unanimously approved and recommended that GulfShore shareholders vote to approve the merger agreement. In considering these facts and the other information contained in this proxy statement/prospectus, you should be aware that certain GulfShore and GulfShore Bank executive officers and directors have financial interests in the merger that are different from, or in addition to, the interests of GulfShore shareholders generally. See “ The Merger — Interests of GulfShore Directors and Executive Officers in the Merger ” on page 51 for information about these financial interests.

The termination fee and the restrictions on third party acquisition proposals set forth in the merger agreement may discourage others from trying to acquire GulfShore.

Until the completion of the merger, with some limited exceptions, GulfShore is prohibited from initiating, soliciting, knowingly inducing or encouraging, or knowingly taking any action to facilitate, or participating in any discussions or negotiations concerning, a proposal to acquire GulfShore, such as a merger or other business combination transaction, with any person other than Seacoast. In addition, GulfShore has agreed to pay to Seacoast in certain circumstances a termination fee equal to $2,125,000. These provisions could discourage other companies from trying to acquire GulfShore even though those other companies might be willing to offer greater value to GulfShore shareholders than Seacoast has offered in the merger. The payment of any termination fee could also have an adverse effect on GulfShore’s financial condition. See “ The Merger Agreement — GulfShore Board Recommendation ” beginning on page 61 and “ The Merger Agreement — Termination Fee ” beginning on page 66 of this proxy statement/prospectus.

Failure of the merger to be completed, the termination of the merger agreement or a significant delay in the consummation of the merger could negatively impact Seacoast and GulfShore.

If the merger is not consummated, the ongoing business, financial condition and results of operations of each party may be materially adversely affected and the market price of Seacoast’s common stock may decline significantly, particularly to the extent that the current market price reflects a market assumption that the merger will be consummated. If the consummation of the merger is delayed, the business, financial condition and results of operations of each company may be materially adversely affected. If the merger agreement is terminated and GulfShore’s board of directors seeks another merger or business combination, GulfShore’s shareholders cannot be certain that GulfShore will be able to find a party willing to engage in a transaction on more attractive terms than the merger.

Some of the performing loans in the GulfShore loan portfolio being acquired by Seacoast may be under-collateralized, which could affect Seacoast’s ability to collect all of the loan amount due.

In an acquisition transaction, the purchasing financial institution may be acquiring under-collateralized loans from the seller. Under-collateralized loans are risks that are inherent in any acquisition transaction and are mitigated through the loan due diligence process that the purchaser performs and the estimated fair market value adjustment that the purchaser places on the seller’s loan portfolio. The year a loan was originated can impact the current value of the collateral. Many Florida banks have performing loans that are under-collateralized because of the decline in real estate values during the 2006 through 2010 economic downturn. While real estate values generally commenced stabilizing in 2011, and in some markets began to increase in recent years, nonetheless like other financial services institutions, GulfShore’s and Seacoast’s loan portfolios have under-collateralized loans that are still performing.

TABLE OF CONTENTS

When it acquires another loan portfolio, Seacoast will place what is referred to as a fair market value adjustment on the acquired loan portfolio to address certain risk characteristics, including those inherent to collateral and credit. Credit characteristics include but are not limited to product type, collateral type, vintage, credit score, lien position, risk rating, loan terms and payment performance. A discount rate is applied to the risk-adjusted expected cash flow to calculate the present value of the loan portfolio. With respect to the GulfShore loan portfolio, Seacoast has placed a preliminary $3.5 million fair value total adjustment. Seacoast has engaged a third party valuation firm that assisted in valuing the acquired portfolio as of the acquisition date. There is no assurance that this preliminary adjustment is sufficient for this loan portfolio.

Risks Associated with Seacoast’s Business

New lines of business or new products and services may subject Seacoast to additional risks.

From time to time, Seacoast may implement or may acquire new lines of business or offer new products and services within existing lines of business. There are substantial risks and uncertainties associated with these efforts, particularly in instances where the markets are not fully developed. In developing and marketing new lines of business and/or new products and services, Seacoast may invest significant time and resources. Initial timetables for the introduction and development of new lines of business and/or new products or services may not be achieved and price and profitability targets may not prove feasible. External factors, such as compliance with regulations, competitive alternatives and shifting market preferences, may also impact the successful implementation of a new line of business or a new product or service. Furthermore, any new line of business and/or new product or service could have a significant impact on the effectiveness of Seacoast’s system of internal controls. Failure to successfully manage these risks in the development and implementation of new lines of business or new products or services could have a material adverse effect on Seacoast’s business, financial condition and results of operations.

An interruption in or breach in security of Seacoast’s information systems may result in a loss of customer business and have an adverse effect on Seacoast’s results of operations, financial condition and cash flows.

Seacoast relies heavily on communications and information systems to conduct its business. Any failure, interruption or breach in security of these systems could result in failures or disruptions in Seacoast’s customer relationship management, general ledger, deposits, servicing or loan origination systems. If any such failures, interruptions or security breaches of its communications or information systems occur, they may not be adequately addressed by Seacoast. Further, the occurrence of any such failures, interruptions or security breaches could damage Seacoast’s reputation, result in a loss of customer business, subject Seacoast to additional regulatory scrutiny or expose Seacoast to civil litigation and possible financial liability, any of which could have a material adverse effect on Seacoast’s results of operations, financial condition and cash flows.

TABLE OF CONTENTS

TABLE OF CONTENTS

INFORMATION ABOUT THE GULFSHORE SPECIAL MEETING

This section contains information about the special meeting that GulfShore has called to allow GulfShore shareholders to vote on the approval of the merger agreement. The GulfShore board of directors is mailing this proxy statement/prospectus to you, as a GulfShore shareholder, on or about February 15, 2017. Together with this proxy statement/prospectus, the GulfShore board of directors is also sending you a notice of the special meeting of GulfShore shareholders and a form of proxy that the GulfShore board of directors is soliciting for use at the special meeting and at any adjournments or postponements of the special meeting.

Time, Date, and Place

The special meeting is scheduled to be held on Monday, March 27, 2017 at 10:00 a.m., local time, at 401 South Florida Avenue, Suite 300, Tampa, Florida 33602.

Matters to be Considered at the Meeting

At the special meeting, GulfShore shareholders will be asked to consider and vote on:

At this time, the GulfShore board of directors is unaware of any other matters that may be presented for action at the special meeting. If any other matters are properly presented, however, and you have completed, signed and submitted your proxy, the person(s) named as proxy will have the authority to vote your shares in accordance with his or her judgment with respect to such matters. A copy of the merger agreement is included in this proxy statement/prospectus as Appendix A, and we encourage you to read it carefully in its entirety.

Recommendation of the GulfShore Board of Directors

The GulfShore board of directors unanimously recommends that GulfShore shareholders vote “ FOR ” the merger proposal and “ FOR ” the adjournment proposal. See “ The Merger — GulfShore’s Reasons for the Merger and Recommendations of the GulfShore Board of Directors .”

Record Date and Quorum

February 10, 2017 has been fixed as the record date for the determination of GulfShore shareholders entitled to notice of, and to vote at, the special meeting and any adjournment or postponement thereof. At the close of business on the record date, there were 5,464,308 shares of GulfShore common stock outstanding and entitled to vote at the special meeting, held by approximately 166 holders of record.

A quorum is necessary to transact business at the special meeting. The presence, in person or by proxy, of the holders of a majority of the outstanding shares of GulfShore common stock entitled to vote at the meeting is necessary to constitute a quorum. Shares of GulfShore common stock represented at the special meeting but not voted, including shares that a shareholder abstains from voting and shares held in “street name” with a bank, broker or other nominee for which a shareholder does not provide voting instructions, will be counted for purposes of establishing a quorum. Once a share of GulfShore common stock is represented at the special meeting, it will be counted for the purpose of determining a quorum not only at the special meeting but also at any adjournment or postponement of the special meeting. In the event that a quorum is not present at the special meeting, it is expected that the special meeting will be adjourned or postponed.

Required Vote

The affirmative vote of the holders of a majority of the outstanding shares of GulfShore common stock must vote in favor of the proposal to approve the merger agreement. If you vote to “ ABSTAIN ” with respect

TABLE OF CONTENTS

to the merger proposal or if you fail to vote on the merger proposal, or fail to instruct your bank or broker how to vote with respect to the merger proposal, this will have the same effect as voting “ AGAINST ” the merger proposal.

The adjournment proposal will be approved if the votes of GulfShore common stock cast in favor of the adjournment proposal exceed the votes cast against the adjournment proposal. If you vote to “ ABSTAIN ” with respect to the adjournment proposal or if you fail to vote on the adjournment proposal, or fail to instruct your bank or broker how to vote with respect to the adjournment proposal, this will have no effect on the outcome of the vote on the adjournment proposal.

Each share of GulfShore common stock you own as of the record date for the special meeting entitles you to one vote at the special meeting on all matters properly presented at the meeting.

How to Vote — Shareholders of Record

Voting in Person .  If you are a shareholder of record, you can vote in person by submitting a ballot at the special meeting. Nevertheless, we recommend that you vote by proxy as promptly as possible, even if you plan to attend the special meeting. This will ensure that your vote is received. If you attend the special meeting, you may vote by ballot, thereby canceling any proxy previously submitted.

Voting by Proxy .  Your proxy card includes instructions on how to vote by mailing in the proxy card. If you choose to vote by proxy, please mark each proxy card you receive, sign and date it, and promptly return it in the envelope enclosed with the proxy card. If you sign and return your proxy without instruction on how to vote your shares, your shares will be voted “ FOR ” the merger proposal and “ FOR ” the adjournment proposal. At this time, the GulfShore board of directors is unaware of any other matters that may be presented for action at the special meeting. If any other matters are properly presented, however, and you have signed and returned your proxy card, the person(s) named as proxy will have the authority to vote your shares in accordance with his or her judgment with respect to such matters. Please do not send in your stock certificates with your proxy card. You will receive a separate letter of transmittal and instructions on how to surrender your GulfShore stock certificates for the merger consideration.

How to Vote — Shares Held in “Street Name”

If you are a GulfShore shareholder and your shares are held in “street name” through a bank, broker or other holder of record, you must provide the record holder of your shares with instructions on how to vote your shares. Please follow the voting instructions provided by the bank, broker or other nominee. You may not vote shares held in street name by returning a proxy card directly to GulfShore or by voting in person at the GulfShore special meeting unless you provide a “legal proxy,” which you must obtain from your bank, broker or other nominee. Further, brokers, banks or other nominees who hold shares of GulfShore common stock on behalf of their customers may not give a proxy to GulfShore to vote those shares with respect to any of the proposals without specific instructions from their customers, as brokers, banks and other nominees do not have discretionary voting power on these matters. Therefore, if you are a GulfShore shareholder and you do not instruct your broker, bank or other nominee on how to vote your shares:

YOUR VOTE IS IMPORTANT.  WHETHER OR NOT YOU PLAN TO ATTEND THE SPECIAL MEETING IN PERSON, PLEASE MARK, SIGN AND DATE THE ENCLOSED PROXY CARD AND PROMPTLY RETURN IT IN THE ENCLOSED POSTAGE-PAID ENVELOPE. SHAREHOLDERS WHO ATTEND THE SPECIAL MEETING MAY REVOKE THEIR PROXIES BY VOTING IN PERSON.

TABLE OF CONTENTS

Revocation of Proxies

You can revoke your proxy at any time before your shares are voted. If you are a shareholder of record, then you can revoke your proxy by:

If you choose to send a completed proxy card bearing a later date or a notice of revocation, the new proxy card or notice of revocation must be received before the beginning of the special meeting. Attendance at the special meeting will not, in and of itself, constitute revocation of a proxy. If you hold your shares in street name with a bank, broker or other nominee, you must follow the directions you receive from your bank, broker or other nominee to change your vote. Your last vote will be the vote that is counted.

Shares Subject to Voting and Joinder Agreements; Shares Held by Directors

A total of 3,511,475 shares of GulfShore common stock, representing approximately 64.26% of the outstanding shares of GulfShore common stock entitled to vote at the special meeting are subject to voting and joinder agreements between Seacoast and each of GulfShore’s directors and related affiliates, and certain executive officers. Pursuant to his, her, or its respective voting and joinder agreement, each such director, director-affiliate, and officer has agreed to, at any meeting of GulfShore shareholders, however called, or any adjournment or postponement thereof (and subject to certain exceptions), vote (or cause to be voted) his, her, or its shares of GulfShore common stock beneficially owned by such director, director-affiliate or officer:

If the GulfShore board of directors makes a company subsequent determination in accordance with the terms of the merger agreement (see the section entitled “The Merger Agreement — GulfShore Board Recommendation on page 61 of this proxy statement/prospectus) only 46.63% of the shares owned by a shareholder who is party to a voting and joinder agreement (approximately 29.5% of the outstanding shares of GulfShore common stock entitled to vote at the special meeting) will be required to be voted as set forth above.

Further, without the prior written consent of Seacoast, each director, director-affiliate and officer who is party to a voting and joinder agreement has agreed not to sell or otherwise transfer any shares of GulfShore common stock and has agreed that he, she, or it will be bound by certain terms of the merger agreement as if he, she, or it was a party thereto, including by releasing Seacoast, its affiliates, and certain related parties from claims related to GulfShore arising prior to the closing of the merger. The foregoing summary of the voting and joinder agreements entered into by GulfShore’s directors, director-affiliates, and certain executive officers does not purport to be complete, and is qualified in its entirety by reference to the form of voting and joinder agreement attached as Exhibit A to the merger agreement, which is attached as Appendix A to this document.

TABLE OF CONTENTS

For more information about the beneficial ownership of GulfShore common stock by each greater than 5% beneficial owner, each director and executive officer and executive officers as a group, see “ Beneficial Ownership of GulfShore Common Stock by Management and Principal Shareholders of GulfShore .”

Solicitation of Proxies

The proxy for the special meeting is being solicited on behalf of the GulfShore board of directors. GulfShore will bear the entire cost of soliciting proxies from you. GulfShore will reimburse brokerage firms and other custodians, nominees and fiduciaries for reasonable expenses incurred by them in sending proxy materials to the beneficial owners of GulfShore stock. GulfShore may use its directors, officers and employees, who will not be specially compensated, to solicit proxies from GulfShore shareholders, either personally or by telephone, facsimile, letter or other electronic means.

Attending the Meeting

All holders of GulfShore common stock, including shareholders of record and shareholders who hold their shares in street name through banks, brokers or other nominees, are cordially invited to attend the special meeting. Shareholders of record can vote in person at the special meeting. If you are not a shareholder of record and would like to vote in person at the special meeting, you must produce a legal proxy executed in your favor by the record holder of your shares. In addition, you must bring a form of personal photo identification with you in order to be admitted at the special meeting. We reserve the right to refuse admittance to anyone without proper proof of share ownership or without proper photo identification. The use of cameras, sound recording equipment, communications devices or any similar equipment during the special meeting is prohibited without GulfShore’s express written consent.

Questions and Additional Information

If you have more questions about the merger or how to submit your proxy or vote, or if you need additional copies of this proxy statement/prospectus or the enclosed proxy card or voting instructions, please contact Balbina Hyler, Corporate Secretary of GulfShore, at (813) 418-3031.

TABLE OF CONTENTS

TABLE OF CONTENTS

At the August 4, 2016 meeting, investment bankers from Sandler O’Neill’s and the other investment banking firm’s financial institution practices met with the board to assist the board in answering the strategic and sale process questions, as well as submit their proposals to represent the GulfShore board as independent financial advisor in connection with a potential business combination. Each firm presented details on its credentials and relevant transaction experience, relevant knowledge of and relationships with prospective buyers, how they would approach the sale process, and the terms of their respective engagement proposals as independent financial advisor. Each firm also reviewed various marketing approaches, and based on dialogue with the board and executive management, provided further input on a “targeted auction process” to sell GulfShore.

At the August 4, 2016 meeting, following the discussions with the investment banking firms, the board unanimously voted to immediately move forward with a sale process. Further, the board discussed the two investment banking firms’ proposals and concluded by voting unanimously to engage Sandler O’Neill to advise the GulfShore board in the sale process. After discussion of whether to create a special committee of the board to facilitate the sale process, the board concluded that because of the relative availability of board members for meetings, as well as the depth of merger and acquisition experience of various board members and executive management, it would be unnecessary to constitute a special committee for purposes of the process.

During the period from August 1 through August 5, 2016, GulfShore’s senior management, with input and review from GulfShore’s legal counsel, Foley & Lardner LLP (“Foley”), finalized the engagement of Sandler O’Neill to advise GulfShore in the sale process. A final engagement letter with Sandler O’Neill was executed on August 5, 2016.

During the period from August 5, 2016 through September 21, 2016, Sandler O’Neill and GulfShore’s senior management team advanced sale process preparations, including finalizing a targeted buyers list and the completion of customary marketing materials (including a confidential information memorandum and proposed form of nondisclosure agreement). This process also included population of a virtual data room with customary due diligence materials on GulfShore and as commonly requested by prospective buyers. At GulfShore’s direction, Sandler O’Neill proceeded to make contact with the targeted buyer list, which included a high priority group of 10 prospective buyers. The group included public and private banking companies, regional banks, non-Florida based banks, and Florida-based banks, and it included prospective buyers with total assets ranging from approximately $1 billion to $20 billion.

As a result of this process, GulfShore entered into nondisclosure agreements with nine prospective buyers, including Seacoast, who performed varying levels of due diligence. The executive management team met with six prospective buyers, and ultimately received six letters of intent, including from Seacoast. GulfShore’s senior executive management held various calls and in-person meetings with the prospective buyers. Similarly, the meetings presented management with initial opportunities for high-level reverse due diligence inquiries. In late September 2016, Foley and GulfShore, with input from Sandler O’Neill, prepared a draft merger agreement with key terms left blank that Sandler O’Neill distributed to prospective buyers and encouraged the prospective buyers to provide their comments via a markup of the draft merger agreement.

On September 20, 2016, the board held a special meeting with the senior executives and Sandler O’Neill to review the six first round offers from prospective buyers. Sandler O’Neill provided a process overview and a summary of the bids received, and discussed financial aspects of each bid and bidder. The board also discussed and considered potential strategic and cultural fits, integration success histories, and client, employee, and community impacts of the prospective merger partners. In consideration of the preceding, the board unanimously voted to advance with three of the prospective buyers, one of which was Seacoast, on the condition that all indicate a willingness to enhance their proposed pricing and transaction structures. The three final bidders presented indications, which included either all stock, or a stock and cash mix, and with pricing ranging from approximately $9.00 to $10.28 per GulfShore share. Sandler O’Neill was charged by the board with relaying the message to each of the prospective buyers to enhance their offers for further consideration. The other three bidders’ GulfShore chose not to advance with were declined as a result of some, or all of the

TABLE OF CONTENTS

following: lower bid price, undesirable transaction structure, liquidity of consideration (or lack thereof) and potential transaction execution risk (one prospective buyer required a private placement of equity capital in concert with the transaction).

During the period September 21 through October 20, 2016, Sandler O’Neill and management engaged in additional discussions and negotiations with the three finalist bidders. On September 26, one of the remaining bidders indicated an inability to increase its pricing from its initial letter of intent and exited the bidding process. The bidder indicated it performed analysis to increase pricing via various cash and stock mix adjustments, but its capital position became a limiting factor.

Follow-up management meetings were held by the final two bidders, “Bidder A” and Seacoast, and GulfShore’s management.

Bidder A met in-person with GulfShore’s executive management team on September 23, 2016, for further due diligence and advanced discussions, which were primarily focused on strategic approach, the history of each party and their respective approaches to growth, as well as the potential cultural fit of each party. On September 30, 2016, Bidder A communicated to Sandler O’Neill that it would not be moving forward in the bid process. There was no stated reason for the exit provided to Sandler O’Neill or GulfShore management.

Seacoast advanced its due diligence and held an on-site review of loan files during the weekend of October 14, 2016. Additionally, GulfShore’s executive team advanced a more detailed reverse due diligence question-and-answer session with the Seacoast executive team regarding strategic fit, integration plans, valuation approach, potential cost savings, recent merger transaction details and integration activities, and overall forward view of shareholder value creation opportunities as a combined entity.

On October 19, 2016, Seacoast provided a final, non-binding, indication of interest for the purchase of GulfShore. The indication of interest described the proposed transaction and strategic rationale, cultural fit, opportunities for the combined enterprises, and stated that the goal of the combination was to create a premier banking franchise in the Tampa Bay market and that ownership would represent great value to shareholders in terms of investment performance, upside price potential, and liquidity. The indication outlined the proposed purchase price, form of consideration, absence of financing contingencies, and employee approach and opportunities. The indication of interest further stated that due diligence had been completed and further opportunity for reverse diligence would be offered to GulfShore, and it outlined the proposed transaction timing, all subject to regulatory approval and execution of a definitive merger agreement along with other customary items. Seacoast also delivered with its proposal a markup of the definitive merger agreement that had previously been provided to Seacoast by Sandler O’Neill.

On October 20, 2016, the GulfShore board held a special meeting with executive management and Sandler O’Neill to review the second round offers from prospective buyers. As a result of Bidder A backing out of the process, the meeting focused on the indication of interest from Seacoast. Sandler O’Neill reviewed details of the updated bid from Seacoast, which included an increased offer value per share and adjusted consideration mix (of stock and cash). The total offer value, including value of options, was $53.9 million, equating to $9.65 per GulfShore share, and the proposed consideration was a mix of 75% stock and 25% cash. The pricing represented a deal value per GulfShore share requal to the last twelve month’s net income per share multiple of 37.6x; and a deal value per share to September 30, 2016 tangible book value ratio per share of 144%. Sandler O’Neill also observed that in calculating a normalized tangible book value target of 9% (GulfShore’s exceeded 11%), with all excess tangible common equity being paid dollar for dollar, Seacoast’s proposal represented a tangible book value multiple of 154%.

There was then a board discussion regarding the offer details, consideration, impact to shareholders and employees, and market response. Subsequently, the board voted unanimously for Sandler O’Neill to request an improved proposal with an increased price per share from Seacoast. The board determined that the opportunity was favorable and in the best interest of GulfShore and its shareholders, but that a higher valuation was justified and should be pursued before an agreement could be reached. After Sandler O’Neill broke from the board meeting to communicate the board’s position to Seacoast, Seacoast responded with a revised offer of $9.80 per GulfShore share with consideration to consist of an 85% common stock and 15% cash mix. The

TABLE OF CONTENTS

board voted unanimously to accept the revised indication of interest. Seacoast and GulfShore executed a revised indication of interest on October 20, 2016.

GulfShore’s executive management met in-person on October 28, 2016 with Seacoast for reverse due diligence meetings and discussions.

During period from October 20, 2016 through November 2, 2016, Foley and Seacoast’s counsel, Cadwalader, Wickersham & Taft LLP (“Cadwalader”), along with management and financial advisors of both companies, negotiated the terms of the merger agreement and the related ancillary agreements (including the form of voting agreement and form of director restrictive covenant agreement) and came to substantial agreement on or around November 1, 2016.

On November 1, 2016, the GulfShore and GulfShore Bank boards convened a special meeting with their senior executives, Sandler O’Neill, and Foley to review the final negotiated definitive merger agreement and related ancillary documents. Representatives of Sandler O’Neill reviewed the financial aspects of the proposed merger with Seacoast. Foley summarized the material terms of the merger agreement and ancillary agreements, and also reviewed with the GulfShore board the legal standards applicable to the board’s decisions and actions with respect to the proposed merger. Foley then responded to questions, and the GulfShore board engaged in discussion, regarding various transaction terms, including the circumstances under which the board would have the right to entertain superior third-party offers prior to the closing of the merger, the termination fee that would be payable by GulfShore if the merger agreement were terminated under certain circumstances, the affirmative and negative covenants that would be applicable to GulfShore and GulfShore Bank prior to the merger, and the circumstances under which GulfShore could terminate the merger agreement due to decline in the trading price of Seacoast stock prior to the closing.

At the meeting, there was also substantial discussion regarding the restrictive covenant agreement and voting agreement that Seacoast was requiring each GulfShore director to execute. It was discussed that the voting and joinder agreements would require additional modification to allow directors to maintain their fiduciary independence to vote for alternative offers, should they arise during the period between signing of the merger agreement and closing. The board, management, Foley, and Sandler O’Neill discussed potential acceptable modifications to the form of voting and joinder agreement and directed management and Foley to discuss and negotiate potential modifications to the agreement. The special meeting was then adjourned. It was determined a modification whereby only a limited percentage of director shares would be required to vote for the merger agreement could accomplish the goal of Seacoast and maintain directors’ independence and fiduciary responsibilities. The special meeting was then recessed, after which Foley and Cadwalader discussed modifications to the voting and joinder agreement, and it was agreed that, under the voting agreement, each director would be permitted to vote a portion of his or her shares (53.37%) against the merger under certain circumstances relating to receipt of a competing proposal that was superior to the Seacoast merger. Foley and Cadwalader also discussed and agreed to potential revisions to the restrictive covenant agreements requested by the directors. The special meeting was then reconvened later the same day after GulfShore and Seacoast modified the restrictive covenant agreements and voting and joinder agreements. The board reviewed the modified versions of the two agreements with input from Foley. Then the meeting was recessed again to allow Foley and Cadwalader to continue to revise the transaction documents. On November 2, 2016, Sandler O’Neill delivered its written opinion to the GulfShore board of directors to the effect that, as of the date of such opinion, and subject to the procedures followed, assumptions made, matters considered, and qualifications and limitations on the review undertaken by Sandler O’Neill as set forth in its opinion, the merger consideration was fair to the holders of GulfShore common stock from a financial point of view.

On November 3, 2016, the board reconvened its meeting and voted unanimously to approve the merger agreement and voting and joinder agreements. Later the same day, all directors had agreed upon and executed their respective restrictive covenant agreements, and after the close of markets, GulfShore, GulfShore Bank, Seacoast, and Seacoast Bank all executed the merger agreement. A press release announcing the transaction was issued the next morning.

GulfShore’s Reasons for the Merger and Recommendation of the GulfShore Board of Directors

After careful consideration, GulfShore’s board of directors, at a meeting held on November 3, 2016, determined that the merger agreement is in the best interests of GulfShore and its shareholders. Accordingly,

TABLE OF CONTENTS

GulfShore’s board of directors adopted and approved the merger agreement and recommends that GulfShore shareholders vote “FOR” the approval of the merger agreement. In reaching its decision to adopt and approve the merger agreement and the merger and the other transactions contemplated by the merger agreement, and to recommend that its shareholders approve the merger agreement, the GulfShore board of directors consulted with GulfShore’s management, as well as its financial and legal advisors, and considered a number of factors, including the following material factors:

TABLE OF CONTENTS

The foregoing discussion of the factors considered by the GulfShore board of directors is not intended to be exhaustive, but rather includes the material factors considered by the GulfShore board of directors. In reaching its decision to adopt and approve the merger agreement, the GulfShore board of directors did not quantify or assign any relative weights to the factors considered, and individual directors may have given different weights to different factors. The GulfShore board of directors considered all these factors as a whole, including discussions with, and questioning of, GulfShore’s management and GulfShore’s financial and legal advisors, and overall considered the factors to be favorable to, and to support, its determination.

FOR THE REASONS SET FORTH ABOVE, THE GULFSHORE BOARD OF DIRECTORS HAS UNANIMOUSLY ADOPTED AND APPROVED THE MERGER AGREEMENT AND THE TRANSACTIONS CONTEMPLATED THEREBY AND UNANIMOUSLY RECOMMENDS THAT YOU VOTE “FOR” THE MERGER PROPOSAL AND “FOR” THE ADJOURNMENT PROPOSAL.

Seacoast’s Reasons for the Merger

As a part of Seacoast’s growth strategy, Seacoast routinely evaluates opportunities to acquire financial institutions. The acquisition of GulfShore is consistent with Seacoast’s expansion strategy. Seacoast’s board of directors, senior management and other officers of SNB reviewed the business, financial condition, results of operations and prospects for GulfShore, the market condition of the market area in which GulfShore conducts business, the compatibility of the management and the proposed financial terms of the merger. In addition, management of Seacoast believes that the merger will facilitate Seacoast’s entry into the attractive Tampa market area, provide opportunities for future growth and provide the potential to realize cost savings. Seacoast’s board of directors also considered the financial condition and valuation for both GulfShore and Seacoast as well as the financial and other effects the merger would have on Seacoast’s shareholders and stakeholders. The board considered the fact that the acquisition is expected to be accretive and is a low-risk alternative to de novo expansion into Tampa, an attractive market that is adjacent to Orlando, where Seacoast’s acquisitions of Floridian Financial Corporation and the BMO Harris Orlando banking franchise in 2016 made Seacoast the largest Florida-based bank in the MSA. The Tampa metropolitan region ranks itself as one of the fastest growing markets in the state and the country.

While management of Seacoast believes that revenue opportunities will be achieved and costs savings will be obtained following the merger, Seacoast has not quantified the amount of enhancements or projected the areas of operation in which such enhancements will occur.

TABLE OF CONTENTS

In view of the variety of factors considered in connection with its evaluation of the merger, the Seacoast board did not find it useful to and did not attempt to quantify, rank or otherwise assign relative weights to factors it considered. Further, individual directors may have given differing weights to different factors. In addition, the Seacoast board did not undertake to make any specific determination as to whether any particular factor, or any aspect of any particular factor, was favorable or unfavorable to its ultimate determination. Rather, the board conducted an overall analysis of the factors it considered material, including thorough discussions with, and questioning of, Seacoast’s management.

Opinion of GulfShore’s Financial Advisor

GulfShore retained Sandler O’Neill to act as financial advisor to GulfShore’s board of directors in connection with GulfShore’s consideration of a possible business combination. Sandler O’Neill is a nationally recognized investment banking firm whose principal business specialty is financial institutions. In the ordinary course of its investment banking business, Sandler O’Neill is regularly engaged in the valuation of financial institutions and their securities in connection with mergers and acquisitions and other corporate transactions.

Sandler O’Neill acted as financial advisor in connection with the proposed transaction and participated in certain of the negotiations leading to the execution of the merger agreement. On November 2, 2016, Sandler O’Neill delivered to GulfShore’s board of directors its written opinion, dated November 2, 2016, to the effect that, as of such date, the consideration provided for in the merger was fair to the holders of GulfShore common stock from a financial point of view . The full text of Sandler O’Neill’s opinion is attached as Appendix B to this proxy statement/prospectus. The opinion outlines the procedures followed, assumptions made, matters considered and qualifications and limitations on the review undertaken by Sandler O’Neill in rendering its opinion. The description of the opinion set forth below is qualified in its entirety by reference to the full text of the opinion. Holders of GulfShore common stock are urged to read the entire opinion carefully in connection with their consideration of the proposed merger.

Sandler O’Neill’s opinion speaks only as of the date of the opinion. The opinion was directed to GulfShore’s board of directors in connection with its consideration of the merger agreement and the merger and does not constitute a recommendation to any shareholder of GulfShore as to how any such shareholder should vote at any meeting of shareholders called to consider and vote upon the approval of the merger agreement and the merger. Sandler O’Neill’s opinion was directed only to the fairness, from a financial point of view, of the merger consideration to the holders of GulfShore common stock and does not address the underlying business decision of GulfShore to engage in the merger, the form or structure of the merger or any other transactions contemplated in the merger agreement, the relative merits of the merger as compared to any other alternative transactions or business strategies that might exist for GulfShore or the effect of any other transaction in which GulfShore might engage. Sandler O’Neill did not express any opinion as to the fairness of the amount or nature of the compensation to be received in the merger by any officer, director or employee of GulfShore or Seacoast, or any class of such persons, if any, relative to the compensation to be received in the merger by any other shareholder, including the merger consideration to be received by the holders of GulfShore common stock. Sandler O’Neill’s opinion was approved by Sandler O’Neill’s fairness opinion committee.

In connection with its opinion, Sandler O’Neill reviewed and considered, among other things:

TABLE OF CONTENTS

Sandler O’Neill also discussed with certain members of the senior management of GulfShore the business, financial condition, results of operations and prospects of GulfShore and held similar discussions with certain members of the senior management of Seacoast regarding the business, financial condition, results of operations and prospects of Seacoast.

In performing its review, Sandler O’Neill relied upon the accuracy and completeness of all of the financial and other information that was available to and reviewed by it from public sources, that was provided to Sandler O’Neill by GulfShore or Seacoast or their respective representatives or that was otherwise reviewed by Sandler O’Neill, and Sandler O’Neill assumed such accuracy and completeness for purposes of rendering its opinion without any independent verification or investigation. Sandler O’Neill relied on the assurances of the respective managements of GulfShore and Seacoast that they were not aware of any facts or circumstances that would have made any of such information inaccurate or misleading. Sandler O’Neill was not asked to and did not undertake an independent verification of any of such information and did not assume any responsibility or liability for the accuracy or completeness thereof. Sandler O’Neill did not make an independent evaluation or perform an appraisal of the specific assets, the collateral securing assets or the liabilities (contingent or otherwise) of GulfShore or Seacoast or any of their respective subsidiaries, nor was Sandler O’Neill furnished with any such evaluations or appraisals. Sandler O’Neill rendered no opinion or evaluation on the collectability of any assets or the future performance of any loans of GulfShore or Seacoast. Sandler O’Neill did not make an independent evaluation of the adequacy of the allowance for loan losses of GulfShore or Seacoast, or of the combined entity after the merger, and it did not review any individual credit files relating to GulfShore or Seacoast. Sandler O’Neill assumed, with GulfShore’s consent, that the respective allowances for loan losses for both GulfShore and Seacoast were adequate to cover such losses and would be adequate on a pro forma basis for the combined entity.

In preparing its analyses, Sandler O’Neill used certain internal financial projections for GulfShore for the years ending December 31, 2016 through December 31, 2019 and an estimated long-term balance sheet growth rate for the year thereafter, as provided by or discussed with the senior management of GulfShore, as well as publicly available consensus mean analyst estimates for Seacoast for the years ending December 31, 2016, December 31, 2017 and December 31, 2018 and an estimated long-term balance sheet growth rate for the years after December 31, 2017 and an estimated long-term earnings per share growth rate for the years after December 31, 2018, as provided by or discussed with the senior management of Seacoast. Sandler O’Neill also received and used in its pro forma analyses certain assumptions relating to purchase accounting adjustments, cost savings and transaction expenses, as provided by the senior management of Seacoast. With respect to the foregoing information, the respective senior managements of GulfShore and Seacoast confirmed

TABLE OF CONTENTS

to Sandler O’Neill that such information reflected (or, in the case of the publicly available consensus mean analyst estimates referred to above, were consistent with) the best currently available estimates and judgments of those respective senior managements as to the future financial performance of GulfShore and Seacoast, respectively, and the other matters covered thereby, and Sandler O'Neill assumed that the future financial performance reflected in such information would be achieved. Sandler O’Neill expressed no opinion as to such information, or the assumptions on which such information was based. Sandler O’Neill also assumed that there had been no material change in the respective assets, financial condition, results of operations, business or prospects of GulfShore or Seacoast since the date of the most recent financial statements made available to it. Sandler O’Neill assumed in all respects material to its analysis that GulfShore and Seacoast would remain as going concerns for all periods relevant to its analysis.

Sandler O’Neill also assumed, with GulfShore’s consent, that (i) each of the parties to the Agreement would comply in all material respects with all material terms and conditions of the Agreement and all related agreements, that all of the representations and warranties contained in such agreements were true and correct in all material respects, that each of the parties to such agreements would perform in all material respects all of the covenants and other obligations required to be performed by such party under such agreements and that the conditions precedent in such agreements were not and would not be waived, (ii) in the course of obtaining the necessary regulatory or third party approvals, consents and releases with respect to the merger, no delay, limitation, restriction or condition would be imposed that would have an adverse effect on GulfShore, Seacoast or the merger or any related transaction, (iii) the merger and any related transactions would be consummated in accordance with the terms of the merger agreement without any waiver, modification or amendment of any material term, condition or agreement thereof and in compliance with all applicable laws and other requirements, and (iv) the merger would qualify as a tax-free reorganization for federal income tax purposes. Finally, with GulfShore’s consent, Sandler O’Neill relied upon the advice that GulfShore received from its legal, accounting and tax advisors as to all legal, accounting and tax matters relating to the merger and the other transactions contemplated by the merger agreement. Sandler O’Neill expressed no opinion as to any such matters.

Sandler O’Neill’s opinion was necessarily based on financial, economic, market and other conditions as in effect on, and the information made available to it as of, the date of its opinion. Events occurring after the date of its opinion could materially affect Sandler O’Neill’s opinion. Sandler O’Neill has not undertaken to update, revise, reaffirm or withdraw its opinion or otherwise comment upon events occurring after the date of its opinion. Sandler O’Neill expressed no opinion as to the trading values of GulfShore common stock or Seacoast common stock at any time or what the value of Seacoast common stock would be once it is actually received by the holders of GulfShore common stock.

In rendering its opinion, Sandler O’Neill performed a variety of financial analyses. The summary below is not a complete description of the analyses underlying Sandler O’Neill’s opinion or the presentation made by Sandler O’Neill to GulfShore’s board of directors, but is a summary of all material analyses performed by Sandler O’Neill in connection with its opinion and provided by Sandler O’Neill to GulfShore’s board together with its opinion. The summary includes information presented in tabular format. In order to fully understand the financial analyses, these tables must be read together with the accompanying text. The tables alone do not constitute a complete description of the financial analyses. The preparation of a fairness opinion is a complex process involving subjective judgments as to the most appropriate and relevant methods of financial analysis and the application of those methods to the particular circumstances. The process, therefore, is not necessarily susceptible to a partial analysis or summary description. Sandler O’Neill believes that its analyses must be considered as a whole and that selecting portions of the factors and analyses to be considered without considering all factors and analyses, or attempting to ascribe relative weights to some or all such factors and analyses, could create an incomplete view of the evaluation process underlying its opinion. Also, no company included in Sandler O’Neill’s comparative analyses described below is identical to GulfShore or Seacoast and no transaction is identical to the merger. Accordingly, an analysis of comparable companies or transactions involves complex considerations and judgments concerning differences in financial and operating characteristics of the companies and other factors that could affect the public trading values or merger transaction values, as the case may be, of GulfShore and Seacoast and the companies to which they are being compared. In arriving at its opinion, Sandler O’Neill did not attribute any particular weight to any

TABLE OF CONTENTS

analysis or factor that it considered. Rather, Sandler O’Neill made qualitative judgments as to the significance and relevance of each analysis and factor. Sandler O’Neill did not form an opinion as to whether any individual analysis or factor (positive or negative) considered in isolation supported or failed to support its opinion. Rather, Sandler O’Neill made its determination as to the fairness of the merger consideration on the basis of its experience and professional judgment after considering the results of all its analyses taken as a whole.

In performing its analyses, Sandler O’Neill also made numerous assumptions with respect to industry performance, business and economic conditions and various other matters, many of which are beyond the control of GulfShore, Seacoast and Sandler O’Neill. The analyses performed by Sandler O’Neill are not necessarily indicative of actual values or future results, both of which may be significantly more or less favorable than suggested by such analyses. Sandler O’Neill prepared its analyses solely for purposes of rendering its opinion and provided such analyses to GulfShore’s board of directors at its November 2, 2016 meeting. Estimates on the values of companies do not purport to be appraisals or necessarily reflect the prices at which companies or their securities may actually be sold. Such estimates are inherently subject to uncertainty and actual values may be materially different. Accordingly, Sandler O’Neill’s analyses do not necessarily reflect the value of GulfShore common stock or the prices at which GulfShore common stock or Seacoast common stock may be sold at any time. The analyses of Sandler O’Neill and its opinion were among a number of factors taken into consideration by GulfShore’s board of directors in making its determination to approve the merger agreement and should not be viewed as determinative of the merger consideration or the decision of GulfShore’s board of directors or management with respect to the fairness of the merger. The type and amount of consideration payable in the merger were determined through negotiation between GulfShore and Seacoast.

Summary of Proposed Merger Consideration and Implied Transaction Metrics.   Sandler O’Neill reviewed the financial terms of the proposed merger. Using the per share cash consideration and the implied value of the per share stock consideration based on the closing price of Seacoast common stock on November 2, 2016, Sandler O’Neill calculated an aggregate implied transaction value of approximately $54.8 million, or an implied transaction price per share of $9.80. Based upon financial information for GulfShore as of or for the last twelve months (“LTM”) ended September 30, 2016 and for 2016 and 2017 as provided by the senior management of GulfShore, Sandler O’Neill calculated the following implied transaction metrics:

Implied Transaction Price Per Share/Last Twelve Months Earnings Per Share:			38.1x
Implied Transaction Price Per Share/2016E Earnings Per Share:			39.1x
Implied Transaction Price Per Share/2017E Earnings Per Share:			30.8x
Implied Transaction Price Per Share/Book Value Per Share:			146	%
Implied Transaction Price Per Share/Tangible Book Value Per Share:			146	%
Core Deposit Premium (1) :			7.2	%

Stock Trading History.   Sandler O’Neill reviewed the historical stock price performance of Seacoast common stock for the three-year period ended November 2, 2016. Sandler O’Neill then compared the relationship between the stock price performance of Seacoast to stock price movements in the Seacoast Peer Group (as described below) as well as certain stock indices.

Seacoast Three-Year Stock Price Performance

		Beginning November 1, 2013				Ending November 2, 2016
Seacoast			100	%			150.9	%
Seacoast Peer Group			100	%			153.3	%
NASDAQ Bank Index			100	%			123.3	%
S&P 500 Index			100	%			119.1	%

TABLE OF CONTENTS

Comparable Company Analyses.   Sandler O’Neill used publicly available information to compare selected financial information for GulfShore with a group of financial institutions selected by Sandler O’Neill (the “GulfShore Peer Group”). The GulfShore Peer Group consisted of major exchange traded banks and thrifts headquartered in the Southeast and Southwest with assets between $150 million and $900 million and last twelve months return on average assets between 0.25% and 1.00%, excluding announced merger targets. The GulfShore Peer Group consisted of the following companies:

ASB Bancorp, Inc.		Home Federal Bancorp, Inc. of Louisiana
Auburn National Bancorporation, Inc.		HomeTown Bankshares Corporation
Bancorp 34, Inc.		Old Point Financial Corporation
Bank of the James Financial Group, Inc.		Select Bancorp, Inc.
Carolina Trust Bancshares, Inc.		Southwest Georgia Financial Corporation
First US Bancshares, Inc.		Village Bank and Trust Financial Corp.

The analysis compared financial information for GulfShore provided by GulfShore as of or for the twelve months ended September 30, 2016 (unless otherwise noted) with the corresponding publicly available data for the GulfShore Peer Group as of or for the twelve months ended September 30, 2016 (or, if data as of or for the twelve months ended September 30, 2016 was not publicly available, as of or for the twelve months ended June 30, 2016), with pricing data as of November 2, 2016. The analysis also included certain other data for the GulfShore Peer Group. The table below sets forth the data for GulfShore and the high, low, median and mean data for the GulfShore Peer Group.

GulfShore Comparable Company Analysis

		GulfShore				GulfShore Peer Group Median				GulfShore Peer Group Mean				GulfShore Peer Group High				GulfShore Peer Group Low
Total assets (in millions)		$	332			$	534			$	579			$	898			$	287
Loans/Deposits			90.6	%			90.5	%			85.2	%			97.1	%			56.8	%
Non-performing assets (1) /Total assets			0.69	%			1.23	%			1.40	%			4.90	%			0.22	%
Tangible common equity/Tangible assets			11.03	%			10.25	%			9.99	%			13.14	%			6.19	%
Leverage Ratio			10.76	%			10.74	%			10.64	%			12.89	%			8.00	%
Total RBC Ratio			14.04	%			14.82	%			15.25	%			20.57	%			10.69	%
CRE/Total RBC Ratio			226.0	%			221.0	%			224.4	%			413.1	%			135.2	%
Last Twelve Months Return on average assets (2)			0.47	%			0.66	%			0.60	%			0.97	%			0.26	%
Last Twelve Months Return on average equity (2)			4.15	%			6.09	%			5.88	%			10.26	%			2.28	%
Last Twelve Months Net interest margin (2)			3.29	%			3.76	%			3.86	%			5.16	%			3.06	%
Last Twelve Months Efficiency ratio (2)			72.7	%			74.9	%			77.5	%			102.6	%			59.4	%
Price/Tangible book value			—				108	%			109	%			139	%			77	%
Price/Last Twelve Months Earnings per share			—				18.0x				22.3x				37.3x				10.8x
Current Dividend Yield			—				0.4	%			1.0	%			3.2	%			0.0	%
Last Twelve Months Dividend ratio			—				9.2	%			17.5	%			69.1	%			0.0	%
Market value (in millions)			—			$	54			$	63			$	102			$	28

Sandler O’Neill used publicly available information to perform a similar analysis for Seacoast and a group of financial institutions selected by Sandler O’Neill (the “Seacoast Peer Group”). The Seacoast Peer

TABLE OF CONTENTS

Group consisted of major exchange traded banks and thrifts headquartered in the Southeast with assets between $3.0 billion and $7.0 billion, excluding announced merger targets. The Seacoast Peer Group consisted of the following companies:

Ameris Bancorp		First Bancorp
BNC Bancorp		Park Sterling Corporation
CenterState Banks, Inc.		ServisFirst Bancshares, Inc.
City Holding Company		State Bank Financial Corporation
Fidelity Southern Corporation

The analysis compared financial information for Seacoast provided by Seacoast as of or for the twelve months ended September 30, 2016 with the corresponding publicly available data for the Seacoast Peer Group as of or for the twelve months ended September 30, 2016 (or, if data as of or for the twelve months ended September 30, 2016 was not publicly available, as of or for the twelve months ended June 30, 2016), with pricing data as of November 2, 2016. The analysis also compared price to 2016 earnings per share and price to 2017 earnings per share multiples of Seacoast and the Seacoast Peer Group. The table below sets forth the data for Seacoast and the high, low, median and mean data for the Seacoast Peer Group:

Seacoast Comparable Company Analysis

		Seacoast				Seacoast Peer Group Median				Seacoast Peer Group Mean				Seacoast Peer Group High				Seacoast Peer Group Low
Total assets (in millions)		$	4,514			$	4,396			$	4,773			$	6,802			$	3,227
Loans/Deposits			78.9	%			91.3	%			89.5	%			95.4	%			79.3	%
Non-performing assets (1) /Total assets			1.12	%			0.89	%			0.99	%			1.98	%			0.27	%
Tangible common equity/Tangible assets			8.02	%			8.80	%			9.15	%			14.45	%			7.62	%
Leverage Ratio			9.20	%			9.79	%			9.89	%			14.64	%			8.20	%
Total RBC Ratio			13.40	%			12.29	%			12.99	%			17.56	%			10.65	%
CRE/Total RBC Ratio			208.7	%			239.8	%			235.1	%			377.8	%			117.5	%
Last Twelve Months Return on average assets			0.62	%			1.02	%			1.04	%			1.46	%			0.62	%
Last Twelve Months Return on average equity			6.23	%			9.43	%			9.84	%			16.89	%			5.48	%
Last Twelve Months Net interest margin			3.67	%			3.94	%			3.89	%			4.79	%			3.32	%
Last Twelve Months Efficiency ratio			67.5	%			59.1	%			59.4	%			75.7	%			38.5	%
Price/Tangible book value			182	%			197	%			195	%			286	%			143	%
Price/Last Twelve Months Earnings per share			25.3x				17.2x				18.1x				23.7x				15.2x
Price/Median Analyst 2016E Earnings per share			17.0x				15.8x				16.4x				20.8x				14.3x
Price/Median Analyst 2017E Earnings per share			14.4x				13.8x				14.2x				16.9x				11.6x
Current Dividend Yield			0.0	%			1.6	%			1.7	%			3.4	%			0.6	%
Last Twelve Months Dividend ratio			0.0	%			25.4	%			27.4	%			50.7	%			10.1	%
Market value (in millions)		$	646			$	783			$	843			$	1,407			$	396

TABLE OF CONTENTS

Analysis of Selected Nationwide Merger Transactions .  Sandler O’Neill reviewed a group of selected merger and acquisition transactions involving U.S. banks and thrifts (the “Nationwide Transactions”). The Nationwide Precedent Transactions group consisted of transactions with deal values greater than $25 million announced between June 30, 2016 and November 2, 2016 and publicly disclosed targets with total assets between $200 million and $500 million. The National Transactions group was composed of the following transactions:

Acquiror		Target
First Bancshares, Inc.		Iberville Bank
Salem Five Bancorp		Georgetown Bancorp, Inc.
CVB Financial Corp.		Valley Commerce Bancorp
HomeTrust Bancshares, Inc.		TriSummit Bancorp, Inc.
United Community Financial Corp.		Ohio Legacy Corp.
National Commerce Corp.		Private Bancshares, Inc.
Standard Financial Corp		Allegheny Valley Bancorp, Inc.
Stonegate Bank		Insignia Bank
First Defiance Financial		Commercial Bancshares, Inc.
Monona Bankshares, Inc.		MCB Bankshares, Inc.
Middlefield Banc Corp.		Liberty Bank NA
Arbor Bancorp, Inc.		Birmingham Bloomfield Bancshares
Equity Bancshares, Inc.		Community First Bancshares, Inc.

Using the latest publicly available information prior to the announcement of the relevant transaction, Sandler O’Neill reviewed the following transaction metrics: transaction price to last-twelve-months earnings per share, transaction price to tangible book value per share, and core deposit premium. Sandler O’Neill compared the indicated transaction multiples for the merger to the high, low, mean and median multiples of the Nationwide Transactions group.

		GulfShore/ Seacoast				Nationwide Transactions Median				Nationwide Transactions Mean				Nationwide Transactions High				Nationwide Transactions Low
Transaction price/Last Twelve Months earnings per share:			38.1x				18.2x				21.7x				42.2x				9.0x
Transaction price/Tangible book value per share:			146	%			140	%			143	%			177	%			104	%
Core deposit premium:			7.2	%			6.5	%			6.5	%			14.0	%			0.8	%

TABLE OF CONTENTS

Analysis of Selected Regional Merger Transactions . Sandler O’Neill reviewed a group of selected merger and acquisition transactions involving U.S. banks and thrifts headquartered in Florida (the “Regional Transactions”). The Regional Transactions group consisted of transactions with deal values greater than $15 million announced between January 1, 2015 and November 2, 2016 and publicly disclosed targets headquartered in Florida with total assets between $200 million and $600 million. The Regional Transactions group was composed of the following transactions:

Acquiror		Target
CenterState Banks		Platinum Bank Holding Co.
Stonegate Bank		Insignia Bank
Sunshine Bancorp, Inc.		FBC Bancorp, Inc.
Stonegate Bank		Regent Bancorp, Inc.
Seacoast Banking Corporation of Florida		Floridian Financial Group, Inc.
CenterState Banks		Hometown of Homestead Banking Co.
Fidelity Southern Corp.		American Enterprise Bankshares, Inc.
Republic Bancorp, Inc.		Cornerstone Bancorp, Inc.
CenterState Banks		Community Bank of South Florida, Inc.
Ameris Bancorp		Jacksonville Bancorp, Inc.
HCBF Holding Company		OGS Investments, Inc.
National Commerce Corp.		Reunion Bank of Florida
Home BancShares, Inc.		Florida Business BancGroup, Inc.
Seacoast Banking Corporation of Florida		Grand Bankshares, Inc.
Sunshine Bancorp, Inc.		Community Southern Holdings, Inc.
Ameris Bancorp		Merchant & Southern Banks of Florida, Inc.

Using the latest publicly available information prior to the announcement of the relevant transaction, Sandler O’Neill reviewed the following transaction metrics: transaction price to last-twelve-months earnings per share, transaction price to tangible book value per share, and core deposit premium to core deposits. Sandler O’Neill compared the indicated transaction multiples for the merger to the high, low, mean and median multiples of the Regional Transactions group.

		GulfShore/ Seacoast				Regional Transactions Median				Regional Transactions Mean				Regional Transactions High				Regional Transactions Low
Transaction price/Last Twelve Months earnings per share:			38.1x				24.9x				27.0x				66.3x				10.3x
Transaction price/Tangible book value per share:			146	%			142	%			149	%			237	%			111	%
Core deposit premium:			7.2	%			5.8	%			6.8	%			17.0	%			0.9	%

Net Present Value Analyses.   Sandler O’Neill performed an analysis that estimated the net present value per share of GulfShore common stock assuming GulfShore performed in accordance with financial projections for the years ending December 31, 2016 through December 31, 2019 and the estimated long-term balance sheet growth rate for the year thereafter as provided by or discussed with the senior management of GulfShore. To approximate the terminal value of a share of GulfShore common stock at December 31, 2020, Sandler O’Neill applied price to 2020 earnings per share multiples ranging from 12.0x to 22.0x and price to December 31, 2020 tangible book value per share multiples ranging from 90% to 160%. The terminal values were then discounted to present values using different discount rates ranging from 10.0% to 15.0% which were chosen to reflect different assumptions regarding required rates of return of holders or prospective buyers of GulfShore common stock. As illustrated in the following tables, the analysis indicated an imputed range of values per share of GulfShore common stock of $5.27 to $11.80 when applying multiples of earnings per share and $4.35 to $9.46 when applying multiples of tangible book value per share.

TABLE OF CONTENTS

Earnings Per Share Multiples

		Discount Rate				12.0x				14.0x				16.0x				18.0x				20.0x				22.0x
			10.0	%			$6.44				$7.51				$8.58				$9.66				$10.73				$11.80
			11.0	%			$6.18				$7.21				$8.24				$9.27				$10.30				$11.33
			12.0	%			$5.94				$6.93				$7.92				$8.91				$9.89				$10.88
			13.0	%			$5.70				$6.65				$7.61				$8.56				$9.51				$10.46
			14.0	%			$5.48				$6.40				$7.31				$8.22				$9.14				$10.05
			15.0	%			$5.27				$6.15				$7.03				$7.91				$8.79				$9.66

Tangible Book Value Per Share Multiples

		Discount Rate				90%				104%				118%				132%				146%				160%
			10.0	%			$5.32				$6.15				$6.97				$7.80				$8.63				$9.46
			11.0	%			$5.11				$5.90				$6.70				$7.49				$8.28				$9.08
			12.0	%			$4.90				$5.67				$6.43				$7.19				$7.96				$8.72
			13.0	%			$4.71				$5.45				$6.18				$6.91				$7.64				$8.38
			14.0	%			$4.53				$5.23				$5.94				$6.64				$7.35				$8.05
			15.0	%			$4.35				$5.03				$5.71				$6.39				$7.06				$7.74

Sandler O’Neill also considered and discussed with the GulfShore board of directors how this analysis would be affected by changes in the underlying assumptions, including variations with respect to net income. To illustrate this impact, Sandler O’Neill performed a similar analysis assuming GulfShore’s net income varied from 20% above projections to 20% below projections. This analysis resulted in the following range of per share values for GulfShore common stock, applying the price to 2020 earnings per share multiples range of 12.0x to 22.0x referred to above and a discount rate of 12.09%.

Earnings Per Share Multiples

		Annual Budget Variance				12.0x				14.0x				16.0x				18.0x				20.0x				22.0x
			(20.0	)%			$4.73				$5.52				$6.31				$7.10				$7.89				$8.68
			(10.0	)%			$5.32				$6.21				$7.10				$7.99				$8.87				$9.76
			(5.0	)%			$5.62				$6.56				$7.49				$8.43				$9.37				$10.30
			0.0	%			$5.92				$6.90				$7.89				$8.87				$9.86				$10.85
			5.0	%			$6.21				$7.25				$8.28				$9.32				$10.35				$11.39
			10.0	%			$6.51				$7.59				$8.68				$9.76				$10.85				$11.93
			20.0	%			$7.10				$8.28				$9.46				$10.65				$11.83				$13.01

Sandler O’Neill also performed an analysis that estimated the net present value per share of Seacoast common stock assuming that Seacoast performed in accordance with publicly available consensus mean analyst estimates for Seacoast for the years ending December 31, 2016, December 31, 2017 and December 31, 2018, and the estimated long-term balance sheet growth rate for the years after December 31, 2017 and estimated long-term annual earnings growth rate for the years after December 31, 2018 as provided by or discussed with the senior management of Seacoast. To approximate the terminal value of Seacoast common stock at December 31, 2020, Sandler O’Neill applied price to 2020 earnings per share multiples ranging from 14.0x to 24.0x and price to December 31, 2020 tangible book value per share multiples ranging from 130% to 220%. The terminal values were then discounted to present values using different discount rates ranging from 9.0% to 14.0% chosen to reflect different assumptions regarding required rates of return of holders or prospective buyers of Seacoast common stock. As illustrated in the following tables, the analysis indicated an imputed range of values per share of Seacoast common stock of $12.51 to $26.24 when applying multiples of earnings per share and $11.22 to $23.23 when applying multiples of tangible book value per share.

TABLE OF CONTENTS

Earnings Per Share Multiples

		Discount Rate				14.0x				16.0x				18.0x				20.0x				22.0x				24.0x
			9.0	%			$15.31				$17.50				$19.68				$21.87				$24.06				$26.24
			10.0	%			$14.69				$16.79				$18.89				$20.99				$23.09				$25.19
			11.0	%			$14.11				$16.12				$18.14				$20.15				$22.17				$24.18
			12.0	%			$13.55				$15.48				$17.42				$19.35				$21.29				$23.22
			13.0	%			$13.02				$14.88				$16.74				$18.60				$20.45				$22.31
			14.0	%			$12.51				$14.30				$16.09				$17.87				$19.66				$21.45

Tangible Book Value Per Share Multiples

		Discount Rate				130%				148%				166%				184%				202%				220%
			9.0	%			$13.73				$15.63				$17.53				$19.43				$21.33				$23.23
			10.0	%			$13.17				$15.00				$16.82				$18.65				$20.47				$22.29
			11.0	%			$12.65				$14.40				$16.15				$17.90				$19.65				$21.41
			12.0	%			$12.15				$13.83				$15.51				$17.19				$18.88				$20.56
			13.0	%			$11.67				$13.29				$14.90				$16.52				$18.14				$19.75
			14.0	%			$11.22				$12.77				$14.32				$15.88				$17.43				$18.98

Sandler O’Neill also considered and discussed with the GulfShore board of directors how this analysis would be affected by changes in the underlying assumptions, including variations with respect to net income. To illustrate this impact, Sandler O’Neill performed a similar analysis assuming Seacoast’s net income varied from 20% above estimates to 20% below estimates. This analysis resulted in the following range of per share values for Seacoast common stock, applying the price to 2020 earnings per share multiples range of 14.0x to 24.0x referred to above and a discount rate of 10.21%.

Earnings Per Share Multiples

		Annual Budget Variance				14.0x				16.0x				18.0x				20.0x				22.0x				24.0x
			(20.0	)%			$11.65				$13.32				$14.98				$16.65				$18.31				$19.98
			(10.0	)%			$13.11				$14.98				$16.86				$18.73				$20.60				$22.47
			(5.0	)%			$13.84				$15.82				$17.79				$19.77				$21.75				$23.72
			0.0	%			$14.57				$16.65				$18.73				$20.81				$22.89				$24.97
			5.0	%			$15.29				$17.48				$19.66				$21.85				$24.03				$26.22
			10.0	%			$16.02				$18.31				$20.60				$22.89				$25.18				$27.47
			20.0	%			$17.48				$19.98				$22.47				$24.97				$27.47				$29.97

Sandler O’Neill noted that the net present value analysis is a widely used valuation methodology, but the results of such methodology are highly dependent upon the numerous assumptions that must be made, and the results thereof are not necessarily indicative of actual values or future results.

Pro Forma Merger Analysis.   Sandler O’Neill analyzed certain potential pro forma effects of the merger, assuming the merger closes at the end of the first calendar quarter of 2017. In performing this analysis, Sandler O’Neill utilized the following information: (i) financial projections for GulfShore for the years ending December 31, 2016 through December 31, 2019 and an estimated long-term balance sheet growth rate for the year thereafter, as provided by or discussed with the senior management of GulfShore; (ii) publicly available consensus mean analyst estimates for Seacoast for the years ending December 31, 2016, December 31, 2017 and December 31, 2018 and an estimated long-term balance sheet growth rate for the years after December 31, 2017 and an estimated long-term earnings per share growth rate for the years after December 31, 2018, as provided by or discussed with the senior management of Seacoast; and (iii) certain assumptions relating to purchase accounting adjustments, cost savings and transaction expenses, as provided by the senior management of Seacoast. The analysis indicated that the merger could be accretive to

TABLE OF CONTENTS

Seacoast’s earnings per share (excluding one-time transaction costs and expenses) in the years ended December 31, 2017, December 31, 2018, December 31, 2019 and December 31, 2020, dilutive to Seacoast’s estimated tangible book value per share at close and at December 31, 2017, December 31, 2018 and December 31, 2019 and accretive to Seacoast’s estimated tangible book value per share at December 31, 2020.

In connection with this analysis, Sandler O’Neill considered and discussed with the GulfShore board of directors how the analysis would be affected by changes in the underlying assumptions, including the impact of final purchase accounting adjustments determined at the closing of the transaction, and noted that the actual results achieved by the combined company may vary from projected results and the variations may be material.

Sandler O’Neill’s Relationship.   Sandler O’Neill has acted as GulfShore’s financial advisor in connection with the merger and will receive a fee for its services in an amount currently estimated to be approximately $585,000, a substantial portion of which fee is contingent upon the closing of the merger. Sandler O’Neill also received a $150,000 fee upon rendering its fairness opinion to the GulfShore Board of Directors, which will be credited in full towards the transaction fee which will become payable to Sandler O’Neill on the day of closing of the merger. GulfShore has also agreed to indemnify Sandler O’Neill against certain claims and liabilities arising out of its engagement and to reimburse Sandler O’Neill for certain of its out-of-pocket expenses incurred in connection with its engagement.

Sandler O’Neill did not provide any other investment banking services to GulfShore in the two years preceding the date of this opinion. In the two years preceding the date of its opinion, Sandler O’Neill has provided certain investment banking services to Seacoast and received fees for such services. In 2015, Sandler O'Neill was engaged as Seacoast’s financial advisor in connection with Seacoast’s acquisition of Grand Bankshares, Inc. In the ordinary course of its business as a broker-dealer, Sandler O’Neill may purchase securities from and sell securities to GulfShore and its affiliates. Sandler O’Neill may also actively trade the equity and debt securities of Seacoast and their respective affiliates for its own account and for the accounts of its customers.

Certain Unaudited Prospective Financial Information of GulfShore

Background

GulfShore does not as a matter of course make public projections as to future earnings or other results due to, among other reasons, the inherent uncertainty of and changes to the underlying assumptions and estimates. In connection with the proposed merger, however, GulfShore senior management provided to Sandler O'Neill, GulfShore’s financial advisor, for purposes of performing its financial analyses described above under “ The Merger — Opinion of GulfShore’s Financial Advisor ,” and to Seacoast, for purposes of its due diligence review of GulfShore, certain unaudited prospective financial information with respect to GulfShore.

This non-public unaudited prospective financial information was not prepared with a view toward public disclosure or with a view toward complying with the guidelines established by the American Institute of Certified Public Accountants with respect to prospective financial information or published guidelines of the SEC regarding forward-looking statements or GAAP, but, in the view of GulfShore’s management, was prepared on a reasonable basis, reflected the best then-available estimates and judgments and presented, to the best of GulfShore management’s knowledge and belief, the expected course of action and the expected future financial performance of GulfShore on a standalone basis. A summary of certain significant elements of the unaudited prospective financial information prepared by the management of GulfShore is set forth below and is included in this proxy statement/prospectus because such information was made available to Sandler O'Neill in connection with the preparation of its fairness opinion, as well as to Seacoast.

The following unaudited prospective financial information was prepared solely for internal use and is subjective in many respects. The unaudited prospective financial information reflects numerous estimates and assumptions made with respect to business, economic, market, competition, regulatory and financial conditions and matters specific to GulfShore and its respective business, all of which are difficult to predict and many of which are beyond GulfShore’s or Seacoast’s control. The unaudited prospective financial information reflects both assumptions as to certain business decisions that are subject to change and, in many respects, subjective

TABLE OF CONTENTS

judgment, and thus is susceptible to multiple interpretations and periodic revisions based on actual experience and business developments. Neither GulfShore nor Seacoast can give any assurance that the unaudited prospective financial information and the underlying estimates and assumptions will be realized. In addition, because the unaudited prospective financial information covers multiple years, such information by its nature becomes less predictive with each successive year. Actual results may differ materially from those set forth below, and important factors that may affect actual results and cause the unaudited prospective financial information to be inaccurate include, but are not limited to, risks and uncertainties relating to GulfShore’s business, banking industry performance, general business and economic conditions, customer requirements, competition and adverse changes in applicable laws, regulations or rules. For other factors that could cause actual results to differ, please see the sections entitled “ Cautionary Statement About Forward-Looking Statements ” and “ Risk Factors ” beginning on page 25 and page 20, respectively, of this proxy statement/prospectus.

GulfShore’s independent registered public accounting firm has not compiled, examined or performed any procedures with respect to the accompanying unaudited prospective financial information contained herein, nor have they expressed any opinion or any other form of assurance on such information or its achievability, and assume no responsibility for, and disclaim any association with, such information.

By including in this proxy statement/prospectus a summary of certain financial forecasts, neither GulfShore nor Seacoast, nor any of their respective representatives, has made or makes any representation to any person regarding the ultimate performance of GulfShore compared to the information contained in the financial forecasts. GulfShore and Seacoast do not undertake any obligation to update or otherwise revise the financial forecasts or financial information to reflect circumstances existing since their preparation or to reflect the occurrence of subsequent or unanticipated events, even in the event that any or all of the underlying assumptions are shown to be in error, or to reflect changes in general economic or industry conditions.

Projections Prepared by GulfShore Management

The following table presents selected unaudited financial information from GulfShore Bank on a standalone basis (without giving effect to the proposed merger) for the years ending December 31, 2016 through December 2019 prepared by GulfShore's management as of June 2016.

GulfShore Bank
(dollars in thousands, except per share data)		2016				2017				2018				2019
Total Assets		$	341,032.2			$	374,896.5			$	426,024.7			$	486,352.2
Net Income			1,377.3				1,751.4				2,726.2				3,702.5
Earnings per Share (1)			0.25				0.32				0.50				0.68

(1)

For GulfShore Bancshares, Inc. and based on basic share count as of June 30, 2016 (excluding options)

Material U.S. Federal Income Tax Consequences of the Merger

The following section summarizes the anticipated material U.S. federal income tax consequences of the merger generally applicable to U.S. holders (as defined below) of GulfShore common stock. These opinions and the following discussion are based on, and subject to, the Code, the Treasury regulations promulgated under the Code, existing interpretations, court decisions, and administrative rulings, all of which are in effect as of the date of this proxy statement/prospectus, and all of which are subject to change, possibly with retroactive effect. Any such change could affect the continuing validity of the discussion.

This summary only addresses the material U.S. federal income tax consequences of the merger to the GulfShore shareholders that hold GulfShore common stock as a capital asset within the meaning of Section 1221 of the Code. This summary does not address all aspects of U.S. federal income taxation that may be applicable to GulfShore shareholders in light of their particular circumstances or to GulfShore shareholders subject to special treatment under U.S. federal income tax law, such as:

•

shareholders who are not U.S. holders;

•

pass-through entities or investors in pass-through entities;

TABLE OF CONTENTS

In addition, the discussion does not address any alternative minimum tax or any state, local or foreign tax consequences of the merger, nor does it address any tax consequences arising under the unearned income Medicare contribution tax pursuant to the Health Care and Education Reconciliation Act of 2010.

U.S. Holders

For purposes of this summary, the term “U.S. holder” means a beneficial holder of GulfShore common stock that is:

If a partnership (including any entity or arrangement, domestic or foreign, that is treated as a partnership for U.S. federal income tax purposes) holds GulfShore common stock, the tax treatment of a partner will generally depend on the status of the partners and the activities of the partnership. Partnerships and partners in such a partnership should consult their tax advisers about the tax consequences of the merger to them.

The Merger

The parties intend for the merger to qualify as a “reorganization” within the meaning of Section 368(a) of the Code. It is a condition to GulfShore’s obligation to complete the merger that GulfShore receive an opinion from Hacker, Johnson & Smith PA, dated as of the closing date of the merger, to the effect that the merger will qualify as a “reorganization” within the meaning of Section 368(a) of the Code. It is a condition to Seacoast’s obligation to complete the merger that Seacoast receive an opinion from Cadwalader, Wickersham & Taft LLP, dated as of the closing date of the merger, to the effect that the merger will qualify as a “reorganization” within the meaning of Section 368(a) of the Code. In addition, in connection with the filing of the registration statement of which this document is a part, each of Hacker, Johnson & Smith PA and Cadwalader, Wickersham & Taft LLP has delivered an opinion to GulfShore and Seacoast, respectively, to the same effect as the opinions described above. These opinions will be based on representation letters provided by GulfShore and Seacoast and on customary factual assumptions. None of the opinions described above will be binding on the Internal Revenue Service. GulfShore and Seacoast have not sought and will not seek any ruling from the Internal Revenue Service regarding any matters relating to the merger, and as a result, there can be no assurance that the Internal Revenue Service will not assert, or that a court would not sustain, a position contrary to any of the conclusions set forth below. In addition, if any of the representations or

TABLE OF CONTENTS

assumptions upon which those opinions are based are inconsistent with the actual facts, the United States federal income tax consequences of the merger could be adversely affected. The remainder of this discussion assumes that the merger will qualify as a “reorganization” within the meaning of Section 368(a) of the Code.

As a result of the merger, upon exchanging all of its shares, a U.S. holder of GulfShore common stock will generally recognize gain (but not loss) in an amount equal to the lesser of: (1) the amount of cash treated as received in exchange for GulfShore common stock in the merger (excluding any cash received in lieu of fractional shares of Seacoast common stock) and (2) the excess, if any, of (a) the sum of the amount of cash treated as received in exchange for GulfShore common stock in the merger (excluding any cash received in lieu of fractional shares of Seacoast common stock) plus the fair market value of Seacoast common stock (including the fair market value of any Seacoast fractional shares treated as received in the merger) over (b) such holder’s basis in the GulfShore common stock exchanged. If you acquired different blocks of GulfShore common stock at different times or at different prices, you should consult your individual tax advisor regarding the manner in which gain or loss should be determined.

Except as described in the section entitled “Dividend Treatment” below, any recognized gain will generally be long-term capital gain if, as of the effective date of the merger, your holding period with respect to the surrendered GulfShore common stock exceeds one year. The aggregate tax basis of the Seacoast common stock you receive as a result of the merger (including any fractional shares of Seacoast common stock deemed received) will be the same as your aggregate tax basis in GulfShore common stock you surrender in the merger, decreased by the amount of cash you receive that is treated as received in exchange for GulfShore common stock (excluding any cash received in lieu of a fractional share of Seacoast common stock) and increased by the amount of gain, if any, you recognize in the exchange (excluding any gain resulting from cash received in lieu of a fractional share of Seacoast common stock). The holding period of the Seacoast common stock you receive as a result of the exchange will include the holding period of GulfShore common stock you surrendered in the merger.

Cash In Lieu of Fractional Shares .  If you receive cash in the merger instead of a fractional share interest in Seacoast common stock, you will be treated as having received such fractional share in the merger, and then as having received cash in exchange for such fractional share. Gain or loss would be recognized in an amount equal to the difference between the amount of cash received and your adjusted tax basis allocable to such fractional share. Except as described in the section entitled “Dividend Treatment” below, this gain or loss will generally be a capital gain or loss, and will be long-term capital gain or loss if, as of the effective date of the merger, you have held your shares of GulfShore common stock for more than one year.

Dividend Treatment .  There are certain circumstances in which all or part of the gain you recognize will be treated as a dividend rather than as capital gains. In general, this determination depends upon whether, and to what extent, the merger reduces your deemed percentage share ownership interest in Seacoast. Because the possibility of dividend treatment depends primarily upon your particular circumstances, including the application of certain constructive ownership rules, you should consult your own tax advisor regarding the potential tax consequences of the merger to you.

Backup Withholding and Information Reporting

In general, information reporting requirements may apply to the cash payments made to a U.S. holder in connection with the merger, unless an exemption applies. Backup withholding may be imposed on the above payments if a U.S. holder (1) fails to provide a taxpayer identification number or appropriate certificates or (2) otherwise fails to comply with all applicable requirements of the backup withholding rules.

Any amounts withheld from payments to a U.S. holder under the backup withholding rules are not an additional tax and will be allowed as a refund or credit against its applicable U.S. federal income tax liability, provided the required information is furnished to the IRS. U.S. holders should consult their own tax advisors regarding the application of backup withholding based on their particular circumstances and the availability and procedure for obtaining an exemption from backup withholding.

The foregoing discussion is for general information purposes only and is not intended to be a complete analysis or description of all potential U.S. federal income tax consequences of the merger. The discussion does not address tax consequences which may vary with, or are contingent on, your

TABLE OF CONTENTS

individual circumstances. Moreover, the discussion does not address any non-income tax or any foreign, state or local tax consequences of the merger. Accordingly, you are strongly encouraged to consult with your own tax advisor as to the tax consequences of the merger in your particular circumstances, including the applicability and effect of the unearned income Medicare contribution tax pursuant to the Health Care and Education Reconciliation Act of 2010, the alternative minimum tax and any state, local or foreign and other tax laws and of changes in those laws.

Accounting Treatment

The merger will be accounted for using the acquisition method of accounting with Seacoast treated as the acquiror. Under this method of accounting, GulfShore’s assets and liabilities will be recorded by Seacoast at their respective fair values as of the date of completion of the merger. Financial statements of Seacoast issued after the merger will reflect these values and will not be restated retroactively to reflect the historical financial position or results of operations of Seacoast.

Regulatory Approvals

Under federal law, the merger must be approved (unless such requirement for approval has been waived) by the Federal Reserve and the bank merger must be approved by the OCC. Once the Federal Reserve approves the merger (unless such requirement for approval has been waived), the parties must wait for up to thirty days before completing the merger. With the concurrence of the U.S. Department of Justice and permission from the Federal Reserve, however, the merger may be completed on or after the fifteenth day after approval from the Federal Reserve (unless such requirement for approval has been waived). Similarly, after receipt of approval of the bank merger from the OCC, the parties must wait for up to thirty days before completing the bank merger. If, however, there are no adverse comments from the U.S. Department of Justice and Seacoast receives permission from the OCC to do so, the bank merger may be completed on or after the fifteenth day after approval from the OCC.

There is no assurance as to whether the regulatory approvals will be obtained or as to the dates of the approvals. There also can be no assurance that the regulatory approvals received will not contain any condition that would increase any of the minimum regulatory capital requirements of Seacoast following the bank merger or have a material adverse effect. See “ The Merger Agreement — Conditions to Completion of the Merger .”

The OCC approved the bank merger on February 1, 2017.

Appraisal Rights for GulfShore Shareholders

Holders of GulfShore common stock as of the record date are entitled to appraisal rights under the FBCA. Pursuant to Section 607.1302 of the FBCA, a GulfShore shareholder who does not wish to accept the consideration to be received pursuant to the terms of the merger agreement may dissent from the merger and elect to receive the fair value of his or her shares of GulfShore common stock immediately prior to the date of the special meeting to vote on the proposal to approve the merger agreement, excluding any appreciation or depreciation in anticipation of the merger unless exclusion would be inequitable. Under the terms of the merger agreement, if holders of 2% or more of the outstanding shares of GulfShore common stock validly exercise their appraisal rights, then Seacoast will not be obligated to complete the merger.

In order to exercise appraisal rights, a dissenting GulfShore shareholder must strictly comply with the statutory procedures of Sections 607.1301 through 607.1333 of the FBCA, which are summarized below. A copy of the full text of those Sections is included as Appendix C to this proxy statement/prospectus. GulfShore shareholders are urged to read Appendix C in its entirety and to consult with their legal advisors. Failure to adhere strictly to the requirements of Florida law in any regard will cause a forfeiture of any appraisal rights.

GulfShore shareholders are also subject to the Amended and Restated Stockholders’ Agreement, dated as of February 19, 2014 by and among GulfShore and all of its shareholders, which provides for, among other things, the obligation of all GulfShore shareholders to vote for, consent to and raise no objections against, and not otherwise impede or delay, any sale of GulfShore that holders representing a majority of the outstanding shares of GulfShore have voted to approve. In the event of the foregoing approval, GulfShore shareholders

TABLE OF CONTENTS

have also agreed to waive all dissenters rights, appraisal rights and similar rights in connection with such approved sale. Therefore, if the merger agreement is approved, GulfShore shareholders will be required to waive their statutory appraisal rights.

BECAUSE OF THE COMPLEXITY OF THE PROVISIONS OF FLORIDA LAW RELATING TO DISSENTERS’ APPRAISAL RIGHTS, SHAREHOLDERS WHO ARE CONSIDERING DISSENTING FROM THE MERGER ARE URGED TO CONSULT THEIR OWN LEGAL ADVISORS.

Board of Directors and Management of Seacoast Following the Merger

The members of the board of directors and officers of Seacoast immediately prior to the effective time of the merger will be the directors and officers of the surviving company and will hold office until their respective successors are duly elected and qualified, or their earlier death, resignation or removal.

Information regarding the executive officers and directors of Seacoast is contained in documents filed by Seacoast with the SEC and incorporated by reference into this proxy statement/prospectus, including Seacoast’s Annual Report on Form 10-K for the year ended December 31, 2015 and its definitive proxy statement on Schedule 14A for its 2016 annual meeting, filed with the SEC on March 14, 2016 and April 7, 2016, respectively. See “ Where You Can Find More Information ” and “ Documents Incorporated by Reference. ”

Interests of GulfShore Directors and Executive Officers in the Merger

In the merger, the directors and executive officers of GulfShore will receive the same merger consideration for their GulfShore shares as the other GulfShore shareholders. In considering the recommendation of the GulfShore board of directors that you vote to approve the merger agreement, you should be aware that some of the executive officers and directors of GulfShore may have interests in the merger and may have arrangements, as described below, that may be considered to be different from, or in addition to, those of GulfShore shareholders generally. The GulfShore board of directors was aware of these interests and considered them, among other matters, in reaching its decision to adopt and approve the merger agreement and to recommend that GulfShore shareholders vote in favor of approving the merger agreement. For a more complete description of GulfShore’s reasons for the merger and the recommendations of the GulfShore board of directors, please see the section entitled “ The Merger — Background of the Merger” and “The Merger — GulfShore’s Reasons for the Merger and Recommendations of the GulfShore Board of Directors ” beginning on page 30 of this proxy statement/prospectus. GulfShore’s shareholders should take these interests into account in deciding whether to vote “FOR” the proposal to approve the merger agreement. These interests are described in more detail below, and certain of them are quantified in the narrative below.

Payments under Certain Contracts

GulfShore has entered into employment agreements with each of Mr. Caballero, Mr. O’Carroll, Richard Mocsari, Chief Financial Officer and Senior Vice-President, and Drew Peterson, Chief Credit Officer and Senior Vice-President. As discussed below, the employment agreements with Messrs. Caballero and O’Carroll will be superseded as of the effective time of the merger by their new employment agreements with SNB. Under Messrs. Mocsari and Peterson’s employment agreements, if either experiences a qualifying termination during the twelve months following the closing of the merger, such individual will be entitled to severance equal to one times his annual wages and one year of his benefit premium cost. For purposes of the employment agreements, a qualifying termination occurs if (i) the individual is terminated by GulfShore, (ii) there is a material reduction in the individual’s compensation or employment related benefits, (iii) there is a material change in the individual’s job duties or existing management responsibilities, or a change in title that diminishes the individual’s management responsibilities, reporting hierarchy, or status within GulfShore, or (iv) there is a material change in the individual’s working conditions, including a relocation of GulfShore or a material change in GulfShore’s business objectives or policies. The employment agreements provide for non-competition and non-solicitation covenants for a period of time equivalent to the duration of severance (other than, in the case of the non-competition covenant, severance paid due to termination by GulfShore within one year following a change in control) or, in the case of the non-solicitation covenant, for one-year following a termination for cause or a resignation other than due to good reason.

TABLE OF CONTENTS

Entry into Employment Agreements

As a condition to Seacoast’s entry into and obligation to consummate the merger, SNB and each of Mr. Caballero and Mr. O’Carroll entered into an employment agreement, each effective as of the effective date of the merger with a three year initial term. Each of the employment agreements supersedes in its entirety the existing employment agreement between the respective executive and GulfShore. The employment agreements acknowledge that each executive will be entitled to a one-time cash payment equal to, in the case of Mr. Caballero, $696,000 plus two times his 2016 annual bonus and an amount equal to 24 months of his medical, health and life insurance premiums costs and, in the case of Mr. O'Carroll, $225,000 plus one times his 2016 annual bonus and an amount equal to 12 months of his medical, health and life insurance premiums costs.

Pursuant to Mr. Caballero’s employment agreement, Mr. Caballero will serve as EVP, Tampa Market Executive of SNB. The agreement provides for, among other things, an annual salary of $348,000 per year. If Mr. Caballero is terminated without cause or if Mr. Caballero is required to have a principal place of business more than thirty miles from Tampa during the initial term, Mr. Caballero will be entitled to twelve months of salary payable in ten equal monthly installments, payment of earned but unpaid bonus, and up to twelve months of continued benefits, subject to Mr. Caballero signing a release in favor of Seacoast. The employment agreement also contains restrictive covenants providing for non-recruitment of employees, non-solicitation of customers and non-competition which are effective for a period ending on the later of (x) the third anniversary of the effective date and (y) the first anniversary of Mr. Cabellero’s termination of employment for any reason. The non-competition covenant will not apply following a termination of Mr. Caballero’s employment by SNB without cause after a change in control of SNB or Mr. Cabellero’s termination for cause at any time.

Pursuant to Mr. O’Carroll’s employment agreement, Mr. O’Carroll will serve as SVP, Commercial Banking Manager of SNB. The agreement provides for, among other things, an annual salary of $225,000 per year. If Mr. O’Carroll is terminated without cause or if Mr. O’Carroll is required to have a principal place of business more than thirty miles from Tampa during the initial term, Mr. Caballero will be entitled to up to twelve months of salary payable in ten equal monthly installments, payment of earned but unpaid bonus, and twelve months of continued benefits, subject to Mr. O’Carroll signing a release in favor of Seacoast. The employment agreement also contains restrictive covenants providing for non-recruitment of employees, non-solicitation of customers and non-competition. The non-recruitment and non-solicitation covenants are effective for a period ending on the later of (x) the third anniversary of the effective date and (y) the first anniversary of Mr. O’Carroll’s termination of employment. The non-compete covenant is effective for a period ending on the later of (x) the second anniversary of the effective date and (y) the first anniversary of Mr. O’Carroll’s termination of employment for any reason or his resignation subject to garden leave. The non-competition covenant will not apply following a termination of Mr. O’Carroll’s employment by SNB without cause after a change in control of SNB or Mr. O’Carroll’s termination for cause at any time. Seacoast has the option to extend Mr. O’Carroll’s employment for up to twelve months following his notice of resignation. During such time, Mr. O’Carroll would receive base salary and be subject to the restrictive covenants.

Treatment of GulfShore Option Awards

In the merger, GulfShore stock options held by directors and executive officers of GulfShore will be treated the same as all outstanding GulfShore stock options. For a description of this treatment, please see the section entitled “ The Merger — Treatment of GulfShore Options ” on page 56 of this proxy statement/prospectus. The executive officers hold 177,993 options and the non-employee directors hold 0 options.

Director Restrictive Covenant Agreement; Release

Each member of the GulfShore and GulfShore Bank boards of directors have entered into a restrictive covenant agreement, covering a two-year period commencing with the effective time of the merger, with Seacoast in the form attached as Exhibit D to the merger agreement attached as Appendix A to this document. However, directors would be permitted to serve on other bank boards within the restricted territory after the first anniversary of the restrictive covenant agreement. In addition, each of the members of the GulfShore and

TABLE OF CONTENTS

GulfShore Bank boards of directors have agreed via the voting and joinder agreements entered into concurrently with the signing of the merger agreement to release certain claims against GulfShore occurring prior to the effective time of the merger, effective as of the effective time of the merger.

Indemnification and Insurance

As described under “ The Merger Agreement — Indemnification and Directors’ and Officers’ Insurance ” beginning on page 60 of this proxy statement/prospectus, after the effective time of the merger, Seacoast will indemnify and defend the present and former directors and officers of GulfShore and its subsidiaries against claims pertaining to matters occurring at or prior to the closing of the merger as permitted by GulfShore’s articles of incorporation and bylaws in effect as of the date of the merger agreement and under applicable law. Seacoast also has agreed, for a period of six years after the effective time of the merger, to provide coverage to present and former directors and officers of GulfShore pursuant to GulfShore’s existing directors’ and officers’ liability insurance. This insurance policy may be substituted, but must contain at least the same coverage and amounts, and contain terms no less advantageous than the coverage currently provided by GulfShore. In no event shall Seacoast be required to expend for the tail insurance a premium amount in excess of 200% of the annual premiums paid by GulfShore for its directors’ and officers’ liability insurance in effect as of the date of the merger agreement.

TABLE OF CONTENTS

TABLE OF CONTENTS

under the FBCA. Shares of GulfShore common stock outstanding immediately prior to the effective time of the merger and which are held by a shareholder who does not vote to approve the merger agreement and who properly demands the fair value of such shares pursuant to, and who complies with, the appraisal procedures under the FBCA are referred to as “dissenting shares.” See “ The Merger — Appraisal Rights for GulfShore Shareholders ” and Appendix C — Provisions of Florida Business Corporation Act relating to Appraisal Rights on pages 50 and C- 1 , respectively.

If Seacoast changes the number of or provides for the exchange of shares of Seacoast common stock issued and outstanding prior to the effective time of the merger as a result of a stock split, reverse stock split, stock dividend or distribution, recapitalization, reclassification, exchange or similar transaction with respect to the outstanding Seacoast common stock, then the per share stock consideration will be equitably adjusted.

Based upon the closing sale price of the Seacoast common stock on the Nasdaq Global Select Market of $22.50 on February 8, 2017, the last practicable trading date prior to the printing of this proxy statement/prospectus, the value of the merger consideration was approximately $12.29.

The value of the shares of Seacoast common stock to be issued to GulfShore shareholders in the merger will fluctuate between now and the closing date of the merger. We make no assurances as to whether or when the merger will be completed, and you are advised to obtain current sale prices for the Seacoast common stock. See “ Risk Factors — Because the sale price of the Seacoast common stock will fluctuate, you cannot be sure of the value of the consideration that you will receive in the merger until the closing .”

Procedures for Converting Shares of GulfShore Common Stock into Merger Consideration

TABLE OF CONTENTS

certificate surrendered or will establish to the satisfaction of Seacoast that such tax has been paid or is not required to be paid. The shares of Seacoast common stock constituting the stock portion of the merger consideration may be in uncertificated book-entry form, unless a physical certificate is otherwise required by any applicable law.

Treatment of GulfShore Options

Each GulfShore stock option outstanding and unexercised immediately prior to the effective time of the merger, whether or not vested or exercisable, will be cancelled and automatically converted into the right to receive a cash amount equal to the aggregate number of shares of GulfShore common stock subject to such option multiplied by the excess, if any, of the merger consideration share value over the exercise price of such option (the “option award consideration”). The “merger consideration share value” is the sum of (i) the per share cash consideration of $1.47 plus (ii) the average volume weighted average price of Seacoast common stock for the ten days preceding the closing date multiplied by the per share stock consideration of 0.4807 shares of Seacoast common stock.

Conduct of Business Pending the Merger

Pursuant to the merger agreement, GulfShore has agreed to certain restrictions on its activities until the effective time of the merger. In general, GulfShore has agreed that, except as otherwise permitted by the merger agreement, or as required by applicable law, or with the prior written consent of Seacoast, it will: