PKG Packaging Corp

PACKAGING CORPORATION OF AMERICA

March 23, 2018

Dear PCA Stockholder:

You are cordially invited to attend the 2018 Annual Meeting of Stockholders to be held at our corporate office, located at 1955 West Field Court, Lake Forest, Illinois, on Tuesday, May 15, 2018 at 8:30 a.m., central time.

Following this page is the formal notice of the meeting and our Proxy Statement. Also enclosed is a proxy or voting instruction card, a postage-paid envelope and our 2017 Annual Report to Stockholders.

It is important that your shares are represented at the meeting. Whether or not you expect to attend the meeting, please vote your shares by following the instructions on the enclosed proxy or voting instruction card.

Sincerely,

Mark W. Kowlzan Chairman and Chief Executive Officer

PACKAGING CORPORATION OF AMERICA

1955 West Field Court

Lake Forest, Illinois 60045

(847) 482-3000

NOTICE OF THE

2018 ANNUAL MEETING OF STOCKHOLDERS

May 15, 2018

The Annual Meeting of Stockholders of Packaging Corporation of America will be held at our corporate office located at 1955 West Field Court, Lake Forest, Illinois, on Tuesday, May 15, 2018, beginning at 8:30 a.m., central time. The purpose of the meeting is to:

Only stockholders of record at the close of business on March 19, 2018 are entitled to receive notice of and to vote at the meeting or any postponement or adjournment thereof.

Your vote is important. Whether you plan to attend the meeting or not, you are urged to vote your shares by following the instructions on the enclosed proxy or voting instruction card. If you do attend the meeting, you may vote in person, even if you have returned a proxy card.

By Order of the Board of Directors,

Kent A. Pflederer

Corporate Secretary

March 23, 2018

PACKAGING CORPORATION OF AMERICA

1955 West Field Court

Lake Forest, Illinois 60045

(847) 482-3000

Please note that if you hold your shares in “street name” (that is, through a broker or other nominee), you will need to bring a copy of your voting instruction card or a brokerage statement reflecting your stock ownership as of the record date and check in at the registration desk at the meeting.

What constitutes a quorum?

A quorum is necessary to hold a valid meeting. The presence at the meeting, in person or by proxy, of the holders of a majority of our outstanding common stock on the record date will constitute a quorum for our meeting. Broker non-votes and proxies received but marked as abstentions will be included as present for purposes of establishing a quorum. A broker non-vote occurs when a nominee holding shares for a beneficial owner does not vote on a particular proposal because the nominee does not have discretionary voting power for the particular matter and has not received voting instructions from the beneficial owner. We expect that nominees will not have discretionary authority for Items 1 (Election of Directors) and 3 (Approval of Executive Compensation) and will have discretionary authority for Item 2 (Ratification of Independent Registered Public Accounting Firm).

If a quorum is not present at the annual meeting, the stockholders present may adjourn the annual meeting from time to time, without notice, other than by announcement at the meeting, until a quorum is present or represented. At any such adjourned meeting at which a quorum is present or represented, any business may be transacted that might have been transacted at the original meeting.

How do I vote if shares are held in my name?

If the shares of our common stock are held in your name, you may vote on matters to come before the meeting in two ways:

Your shares will be voted as you indicate. If you return the proxy card but you do not indicate your voting preferences, then the proxies named on the proxy card will vote your shares for all of the directors nominated, and for approval of the other items before the meeting. Should any other matter requiring a vote of stockholders arise, the stockholders confer upon the proxies discretionary authority to vote the shares represented by such proxy on any such other matter in accordance with their best judgment. All of the proxies are our officers.

How do I vote if I hold my shares through a broker, bank or other nominee?

Stockholders whose shares of our common stock are held in street name must either direct the record holder of their shares as to how to vote their shares of our common stock or obtain a proxy from the record holder to vote at the meeting. These stockholders should check the voting instruction cards used by their brokers or nominees for specific instructions on methods of voting, including by telephone or using the Internet.

How do I vote shares I hold in the 401(k) plan?

If you are one of our employees who holds common stock through the PCA Employee Stock Ownership Plan (which holds the PCA common stock in the Packaging Corporation of America Retirement Savings Plan for Salaried Employees, the PCA Common Stock Fund in the Packaging Corporation of America Thrift Plan for Hourly Employees and the PCA Common Stock Fund in the Boise Paper Holdings, L.L.C. Retirement Savings Plan), you will receive from the plan trustee a request for voting instructions with respect to the shares of our common stock representing your proportionate interest in the plans. You are entitled to direct the plan trustee how to vote your proportionate interest of shares in those plans.

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Greatbanc Trust Company (“GTC”) has the responsibility for monitoring the continued investment of PCA common stock held in the plans. GTC is an investment advisor under the Investment Advisors Act of 1940. If you do not elect to vote the proportionate interest of shares you hold in the plans, those shares will be voted by GTC, in its discretion.

How do I change my vote?

If your shares are held in your name, you may revoke your proxy at any time before it is exercised by:

If your shares are held in street name, you must contact your broker or nominee to revoke your proxy. In either case, your last vote will be the vote that is counted.

If your shares are held in the 401(k) plans, you may revoke your previously given voting instructions by filing with Computershare Trust Company, N.A., the tabulator of votes and our transfer agent, either a written notice of revocation or a properly completed and signed voting instruction card bearing a later date. Computershare must receive the notice of revocation or the voting instruction card no later than May 11, 2018.

What vote is required to approve each item?

Election of Directors.     The election of directors at the 2018 annual meeting will be an uncontested election. A “majority of the vote” of the shares present in person or represented by proxy and entitled to vote at the meeting is required for the election of each director (Item 1). Pursuant to our bylaws, a “majority of the vote” is achieved in an uncontested director election if a director receives more votes “for” than “against” his or her election, with abstentions and broker non-votes disregarded.

Other Matters.     The affirmative vote of the majority of the votes present in person or represented by proxy and entitled to vote at the meeting is required to approve the matters in Items 2 and 3. If a stockholder abstains from voting or directs the stockholder’s proxy to abstain from voting on the matters, the shares are considered present at the meeting for such matters, but since they are not affirmative votes for the matters, they will have the same effect as votes against the matters. On the other hand, shares resulting in broker non-votes, if any, are not entitled to vote for such matter and will have no effect on the outcome of the vote.

What happens if a nominee for director does not receive a majority of the vote in an uncontested election?

All nominees for the election of directors at the 2018 annual meeting are incumbent directors currently serving on the board and the election is uncontested. An incumbent director nominee who does not receive the necessary number of votes to be elected at the annual meeting would, under Delaware law, continue to serve on the board as a “holdover director.” However, under our bylaws, any director who fails to receive the necessary number of votes to be elected must tender his or her resignation to the board promptly. Our independent directors (excluding the director who tendered the resignation) would be required to determine whether to accept or reject the resignation, or whether to take any other action. The board would then act on the tendered resignation, and publicly disclose its decision, within 90 days following certification of the stockholder vote.

Who will be tabulating and certifying votes at the meeting?

We have engaged Computershare Trust Company, N.A., our transfer agent, to serve as the tabulator of votes and a representative of Computershare to serve as inspector of election and certify the votes.

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How are we soliciting this proxy?

We are soliciting this proxy on behalf of our board of directors by mail and will pay all expenses associated with this solicitation. We have retained Georgeson Inc. to aid in the solicitation of proxy materials for a fee of $8,500 plus expenses. In addition to mailing these proxy materials, certain of our officers and other employees may, without additional compensation, solicit proxies by further mailing or personal conversations, or by telephone, facsimile or other electronic means. We will also, upon request, reimburse brokers and other persons holding stock in their names, or in the names of nominees, for their reasonable out-of-pocket expenses for forwarding proxy materials to the beneficial owners of our common stock and to obtain proxies.

IMPORTANT NOTICE REGARDING THE AVAILABILITY OF PROXY MATERIALS FOR THE

2018 ANNUAL MEETING OF STOCKHOLDERS TO BE HELD ON TUESDAY, MAY 15, 2018

This proxy statement and our 2017 Annual Report to Stockholders are available at

www.edocumentview.com/PKG

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ELECTION OF DIRECTORS

serve on our board primarily because of his extensive experience with information technology and security, as well as his business experience gained from more than 35 years of service at State Farm.

Hasan Jameel is 63 years old and has served as a director of PCA since May 2008. Dr. Jameel is the Jordan Family Distinguished Professor of Natural Resource Innovation at North Carolina State University. He has served on the faculty at North Carolina State University since 1987. From 1979 to 1987, he was employed by International Paper Company at its corporate research center and in its mill operations. In March 2007, Dr. Jameel was named a TAPPI fellow, which is an award given to individuals who have made extraordinary technical or service contributions to the pulp and paper industry and/or TAPPI. TAPPI is the leading association for the worldwide pulp, paper and converting industries. Dr. Jameel was chosen to serve on our board primarily for his technical expertise in pulp and paper manufacturing and his knowledge of, and familiarity with, paper mill operations, which are core to our business, complemented by his general business acumen.

Robert C. Lyons is 54 years old and has served as a director of PCA since August 2011. Mr. Lyons has served as Chief Financial Officer of GATX Corporation, a rail, marine and industrial equipment leasing company, since November 2004 and as Executive Vice President of GATX since June 2012. Mr. Lyons has been employed by GATX since 1997 and was promoted through the treasury and investor relations departments before being elected Vice President, Investor Relations in 2002. Prior to his employment with GATX, Mr. Lyons worked for the Financial Relations Board and in the corporate banking division of The Bank of Tokyo-Mitsubishi. Mr. Lyons was chosen to serve on our board primarily for his extensive financial and accounting background, experience as a chief financial officer of a public company, and his familiarity with strategic and business issues and risks for companies similarly situated to PCA.

Thomas P. Maurer is 66 years old and has served as a director of PCA since May 2014. Mr. Maurer spent his entire career with Ernst & Young, LLP, a global professional services firm, from 1973 until his retirement in 2011. He served as the global coordinating partner on the audits of large companies primarily in the manufacturing and consumer products industries. Mr. Maurer was a member of the Ernst & Young Global Account Partner Group and he served two terms on the Ernst & Young Partner Advisory Council. Mr. Maurer also served as the leader of the Retail, Consumer Products and Industrial Products Group in Ernst & Young’s Chicago office. Mr. Maurer is also a director of Lamb Weston Holdings, Inc. Mr. Maurer was chosen to serve on our board primarily for his experience working with and assisting similarly situated companies to ours, his extensive financial and accounting background and his knowledge of both the manufacturing industry and PCA.

Samuel M. Mencoff is 61 years old and has served as a director of PCA since January 1999 and served as Vice President of PCA from January 1999 through January 2000. Mr. Mencoff has been employed principally by Madison Dearborn Partners, LLC since 1993 and currently serves as Co-Chief Executive Officer. From 1987 until 1993, Mr. Mencoff served as Vice President of First Chicago Venture Capital. Mr. Mencoff has served on the board of Boise Cascade Company during the past five years. Mr. Mencoff was chosen to serve on our board primarily for his substantial operational and financial experience gained from the acquisition and management of similarly-situated portfolio companies as managing director and Co-Chief Executive Officer of Madison Dearborn.

Roger B. Porter is 71 years old and has served as a director of PCA since May 2005. Mr. Porter is currently the IBM Professor of Business and Government at Harvard University and has served on the faculty at Harvard University since 1977. Mr. Porter also held senior economic policy positions in the Gerald Ford, Ronald Reagan and George H.W. Bush White Houses, serving as special assistant to the President and executive secretary of the Economic Policy board from 1974 to 1977, as deputy assistant to the President and director of the White House Office of Policy Development from 1981 to 1985, and as assistant to the President for economic and domestic policy from 1989 to 1993. Mr. Porter is also a director of Tenneco Inc., Zions Bancorporation and Extra Space Storage Inc. Mr. Porter was chosen to serve on our board primarily for his perspectives and insights gained through his significant business, governmental and public policy experience.

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Thomas S. Souleles is 49 years old and has served as a director of PCA since September 2010, and previously served on PCA’s Board of Directors from 1999 to 2008. Mr. Souleles has been employed principally by Madison Dearborn Partners, LLC since 1995 and currently serves as a Managing Director concentrating on investments in the basic industries sector. Mr. Souleles has served on the board of directors of Boise Cascade Company and Multi Packaging Solutions International Ltd. during the past five years. Mr. Souleles was chosen to serve on our board primarily for his substantial operational and financial experience gained from the acquisition and management of similarly-situated portfolio companies, including several in the paper and forest products industry, as managing director of Madison Dearborn and his expertise in financial analysis.

Paul T. Stecko is 73 years old and has served as a director of PCA since March 1999, including as Chairman from March 1999 through December 2015. He served as a Senior Advisor to PCA through the end of 2017. He served as Executive Chairman of PCA from July 2010 until his retirement as an officer and employee of the company in December 2013. Mr. Stecko served as Chief Executive Officer of PCA from January 1999 to July 2010. From November 1998 to April 1999, Mr. Stecko served as President and Chief Operating Officer of Tenneco Inc. From January 1997 to November 1998, Mr. Stecko served as Chief Operating Officer of Tenneco. From December 1993 through January 1997, Mr. Stecko served as President and Chief Executive Officer of Tenneco Packaging Inc. Prior to joining Tenneco Packaging, Mr. Stecko spent 16 years with International Paper Company. Mr. Stecko is a member of the board of directors of Tenneco Inc. and State Farm Mutual Insurance Company. Mr. Stecko was chosen to serve on our board primarily for his extensive experience in the paper and packaging industries and general business experience, including more than ten successful years as our chief executive officer.

James D. Woodrum is 55 years old and has served as a director of PCA since May 2009. Mr. Woodrum has served as Clinical Professor at the Kellogg School of Management at Northwestern University since September 2013. He served as a member of the faculty of The Wisconsin School of Business at the University of Wisconsin — Madison from 2007 to September 2013. He also has served as a consultant since 2007. Prior to joining University of Wisconsin — Madison, from 1984 to 2006, Mr. Woodrum was employed by Hewitt Associates, a human resources consulting and outsourcing firm, in a variety of positions of increasing responsibility. Mr. Woodrum was chosen to serve on our board primarily for his broad experience in human resources, corporate governance and compensation matters, as well as his experience working with corporate boards and his general business acumen.

The board of directors unanimously recommends a vote

FOR the election of each of the director nominees.

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Determination of Director Independence

Our corporate governance guidelines provide that a majority of the board of directors will consist of independent directors. All of our directors other than Mark W. Kowlzan, our chairman and chief executive officer, and Paul T. Stecko, our former chairman who served as an executive officer from 1999 to 2013 and in an advisory capacity through the end of 2017, are independent and not employed by us. In determining independence of those directors, the nominating and governance committee conducts an annual review and reports its findings to the full board. The nominating and governance committee determines if any material relationships exist that would impair the independence of any of the non-employee directors and makes a recommendation to the board as to the independence of the directors.

A director may not qualify as independent unless the board of directors affirmatively determines that the director has no material relationship with us. The board of directors has not adopted categorical standards of materiality for independence purposes (other than those set forth in the New York Stock Exchange (“NYSE”) listing standards). In connection with the review performed at its February 27, 2018 meeting, the committee and the board were not aware of any relationship that would disqualify a non-employee director from being independent. The board and the nominating and governance committee considered the following relationships in making its determination.

Madison Dearborn Partners, which employs Mr. Mencoff as co-Chief Executive Officer and Mr. Souleles as Managing Director, is a private equity firm that has investments in companies that may purchase products or services from, or provide products and services to, us in the ordinary course of business in amounts that are not material in amount or significance. Mr. Mencoff and Mr. Souleles are not compensated directly or indirectly as a result of any such transactions, do not otherwise have an interest in such transactions and are not involved in any manner in such transactions. Accordingly, we do not consider any such transactions to impair their independence. As Mr. Mencoff may be deemed to beneficially own more than 10% of certain portfolio companies, we report certain of these transactions under “Transactions with Related Persons” elsewhere in this proxy statement.

Based on the report and recommendation of the nominating and governance committee, the board of directors has determined that the following directors and nominees, which constitute nine of the eleven nominees for election to the board, are independent: Cheryl K. Beebe, Duane C. Farrington, Hasan Jameel, Robert C. Lyons, Thomas P. Maurer, Samuel M. Mencoff, Roger B. Porter, Thomas S. Souleles and James D. Woodrum.

2017 Board of Directors Meetings

The board met eight times during 2017. All nominees for election at the 2018 annual meeting attended all meetings of the board and the committees on which he or she was a member held during the year. All of our directors attended the 2017 Annual Meeting of Stockholders, and all of our directors are expected to attend the 2018 Annual Meeting of Stockholders.

Leadership Structure

Effective January 1, 2016, the board determined to combine the roles of Chairman and Chief Executive Officer because of the efficiency and effectiveness of board conduct and proceedings gained from Mr. Kowlzan’s familiarity with our operations as a result of serving as chief executive officer and a director, enabling the board to focus on the most relevant decisions, issues and risks involving the company. As the company’s strategy focuses on operational excellence, the board believes that familiarity with company operations is important to board leadership, which is achieved under the current leadership structures.

To help maintain a strong and appropriate independent director presence, the independent members of the board have elected Mr. Mencoff as the “lead director.” The lead director is an independent director elected by the independent directors on the board. In addition to presiding at executive sessions of independent directors, the

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lead director has the responsibility to: coordinate with the chairman regarding the establishment of the agenda and topics for board and stockholder meetings; retain independent advisors on behalf of the board as the board may determine is necessary or appropriate; serve as a liaison between the management directors and independent directors when circumstances dictate; participate actively in any recruitment of new directors; regularly meet with the CEO to provide board feedback; and perform such other functions as the independent directors may designate from time to time. The independent directors meet in executive sessions at every regularly scheduled board meeting and otherwise as necessary, and met in executive session four times during 2017.

Risk Management

Issues relating to risk management are regularly discussed among management, the board and the audit committee. Financial risks, including risks relating to our internal controls, are presented to, and discussed with the audit committee, including through our annual internal control assessment, periodic internal audit reports and through the annual internal audit plan. The company’s compliance program objectives and achievements are also discussed at least quarterly with the audit committee and annually with the full board. Business and operational risks are discussed with the board at every regularly scheduled meeting through the review of our performance, our business and industry operating conditions and our strategic direction. Management, through the chief financial officer, our internal audit department, our chief technology officer, our general counsel and our chairman and chief executive officer, periodically presents and discusses with the board risk assessments focusing on the key risks to PCA. The most recent presentation and discussion occurred at the February 27, 2018 board meeting. Key topics discussed during the year included the assessment of our environmental, health and safety management and compliance programs, insurance and risk management, our legal compliance programs and objectives, cybersecurity risks, compensation policies and our management of key business and operating risks.

Board Committees

The board has standing nominating and governance, compensation and audit committees. As required under NYSE rules and the committee charters, each of these committees consists solely of independent directors. Additional committee service eligibility requirements for audit committee members and compensation committee members are set forth in the committee charters and described below.

Nominating and Governance Committee

Mr. Porter (Chair), Mr. Mencoff, Mr. Souleles and Mr. Woodrum serve on the nominating and governance committee. The nominating and governance committee met two times during 2017.

The nominating and governance committee’s primary responsibilities include, among other things:

The committee leads our board recruiting and nominating efforts. As the committee believes that the size of the board is appropriate, we have not recruited new directors since 2015. The nominating and governance committee seeks to identify as candidates for director persons from various backgrounds, with a variety of life experiences, with a reputation for integrity and good business judgment, and who have experience in highly responsible positions in professions or industries relevant to the conduct of our business. In selecting potential new candidates, the committee will take into account the current composition of the board and the extent to which a candidate’s particular expertise and experience will complement the expertise and experience of other directors.

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The committee also considers diversity as a factor in seeking new candidates and recruited and elected one ethnically diverse candidate in the last three years, such candidate being the only new director elected to PCA’s board in that time period. The committee believes that the diversity that exists in the board composition is a benefit to PCA, and will continue efforts to recruit candidates from a pool that includes qualified diverse candidates.

Among other things, the primary skills and experience sought by the committee and the board include relevant leadership or technical experience in the paper, packaging and manufacturing sectors, expertise in capital allocation, senior leadership experience in complex business environments, governance and public policy expertise and expertise in finance, accounting and information technology. Multiple board members possess each of these attributes. Accordingly, the committee believes that the board as currently composed adequately satisfies the objectives described above, and recommended the nomination of each member for an additional term.

We have not established term limits or a mandatory retirement age from our board. As our board is focused on our strategic goal of operational excellence, it is important for board members to have a high degree of familiarity with our operations. We believe that experience gained from board service promotes this objective, and has helped lead to a well-functioning and highly performing board. The median tenure of our board members is nine years.

The committee leads annual performance evaluations of the board, its committees and its members. Areas covered include quality of information provided to the board, the quality of interaction between the board and management, the frequency of meetings of the board and the overall effectiveness of board proceedings, conduct and leadership.

For more information on consideration of nominees for our board, see “Other Information —Recommendations for Board Nominated Director Nominees.” The written charter of the nominating and governance committee is available on PCA’s website at www.packagingcorp.com under the section Investor Relations — Corporate Governance.

Compensation Committee

Mr. Woodrum (Chair), Mr. Mencoff, Mr. Porter and Mr. Souleles serve on the compensation committee. Each member of the compensation committee must satisfy all independence standards applicable to compensation committee members as set forth in the rules of the SEC and the listing standards of the New York Stock Exchange. The committee must have two members that qualify as “non-employee directors” pursuant to SEC Rule 16b-3 and “outside directors” for purposes of Section 162(m) of the Internal Revenue Code of 1986, as amended (“Code Section 162(m)”). As composed, the committee satisfies these standards. The committee met six times during 2017.

The compensation committee’s primary responsibilities include, among other things:

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The committee maintains a Section 162(m) subcommittee, which consists of Mr. Woodrum and Mr. Porter. This subcommittee has the responsibility of considering and approving compensation for our executive officers which is intended to qualify as “performance based compensation” under Code Section 162(m). Recent tax legislation has eliminated the “performance based compensation” exemption from Section 162(m)’s deduction limit, subject to transition rules. We will retain the subcommittee for the purpose of certifying attainment of performance goals and otherwise making necessary approvals for compensation that will remain deductible under those transition rules.

The written charters of the compensation committee and the subcommittee are available on PCA’s website at www.packagingcorp.com under the section Investor Relations — Corporate Governance.

The agenda for meetings of the committee and the subcommittee is determined by its chairman with the assistance of Mr. Pflederer, our general counsel and corporate secretary. Mr. Kowlzan and Mr. Pflederer regularly attend meetings. Due to his familiarity with our compensation history, philosophy and objectives, Mr. Stecko also attends meetings of the committee. At meetings in which compensation decisions are made for the named executive officers, the committee or subcommittee meets in executive session with no members of management present. For compensation matters on which the board acts, the chairman of the committee reports the committee’s recommendations on executive compensation to the board. Independent advisors and the human resources department support the committee and the subcommittee in their duties and may be delegated authority to fulfill certain administrative duties regarding the compensation programs. The committee has authority under its charter to retain, approve fees for and terminate advisors, consultants and agents, as it deems necessary to assist in the fulfillment of its responsibilities. Before engaging compensation consultants, independent legal counsel and other compensation advisors, the committee will assess the independence of any such persons, taking into consideration all factors relevant to that person’s independence from management.

The audit committee’s primary responsibilities include, among other things:

Both the independent registered public accounting firm and the internal auditors regularly meet privately with the audit committee and have unrestricted access to the audit committee. The committee meets with the internal auditors and the independent registered public accounting firm, with and without management present, to discuss the results of their examinations, their evaluations of our internal controls and the overall quality of our financial reporting.

The written charter of the audit committee is available on our website at www.packagingcorp.com under the section Investor Relations — Corporate Governance.

Communication with the Board of Directors

Interested parties, including stockholders, may communicate directly with the lead director, the chairman of the audit committee, the board of directors or the independent directors as a group by writing to those individuals or the group at the following address: c/o Kent A. Pflederer, Corporate Secretary, Packaging Corporation of America, 1955 West Field Court, Lake Forest, IL 60045. Correspondence will be forwarded to the appropriate person or persons. When reporting a concern, please supply sufficient information so that the matter may be addressed properly. Although you are encouraged to identify yourself to assist us in effectively addressing your concern, you may choose to remain anonymous, and we will use our reasonable efforts to protect your identity to the extent appropriate or permitted by law. In addition, employees may communicate confidentially any concerns related to our accounting, internal accounting controls or auditing matters, business principles or policies, or suspected violations, by calling the toll-free help line established by us. The toll-free help line is monitored by non-PCA personnel and all calls are communicated to our corporate security department. Any complaints regarding accounting, internal controls or auditing matters are forwarded directly to the chairman of the audit committee and the chief financial officer.

Code of Ethics

All of our employees, including all officers, are required to abide by our long-standing Statement of Business Principles. Also, separate Codes of Ethics for our executive officers and principal accounting personnel, as well as our directors, are in place to help ensure that our business is conducted in a consistently legal and ethical manner. These documents cover all areas of professional conduct, including employment policies, conflicts of interest, fair dealing and the protection of confidential information, as well as strict adherence to all laws and regulations applicable to the conduct of our business. The full text of our Statement of Business Principles and the Codes of Ethics are published on our website at www.packagingcorp.com under the section Investor Relations — Corporate Governance.

We will disclose future amendments to, or waivers from, certain provisions of these Codes of Ethics for executive officers and directors on our website within four business days following the date of such amendment or waiver, if they occur.

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Corporate Governance Guidelines

We have in place Corporate Governance Guidelines governing the function and performance of the board and its committees, which, among other things, sets forth the qualifications and other criteria for director nominees. The current guidelines appear on our website at www.packagingcorp.com under the section Investor Relations — Corporate Governance.

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RATIFICATION OF APPOINTMENT OF THE INDEPENDENT REGISTERED PUBLIC

ACCOUNTING FIRM

requires specific pre-approval before engaging the independent registered public accounting firm. The committee may delegate pre-approval authority to one or more of its members. The member or members to whom such authority is delegated must report, for information purposes only, any pre-approval decisions to the entire audit committee at its next scheduled meeting.

COMPENSATION DISCUSSION AND ANALYSIS

Compensation Objectives

The compensation committee of our board of directors oversees the executive compensation program. The committee intends for the program to accomplish the following:

The committee believes that these objectives have been accomplished, with the company’s management driving consistently strong performance in our industry and substantial returns for our investors since our inception.

2017 Summary

PCA continued its strong performance in 2017, with record earnings, production and corrugated products volume and continued execution of its growth strategy, culminating in substantial value creation for its shareholders. Earnings per share, excluding special items ¹ , improved from $4.88 in 2016 to $6.02 in 2017. Reported earnings, including special items, improved from $4.75 per share in 2016 to $7.07 in 2017. The company’s packaging segment, paper segment and whole company EBITDA margins led their respective industries, when compared to other domestic public companies in our industries. The company continued to execute on its strategy to grow profitably, with the acquisition of Sacramento Container and its announced conversion of the Wallula white papers machine to containerboard. The company also benefited from its accretive acquisitions made in recent years with profitable contributions from the TimBar and Columbus Container operations acquired in 2016.

PCA’s stock price improved from $84.82 at the beginning of the year to $120.55 at the end of the year. Through the end of 2017, PCA’s one, three and five year cumulative total shareholder return (assuming reinvestment of dividends) is as follows:

PCA’s executive compensation levels for 2017 increased, primarily due to higher annual incentive compensation and long-term equity compensation. PCA’s annual cash incentive awards increased by approximately 6% primarily as a result of record earnings and strong margin performance. PCA increased annual equity compensation by approximately 10%, primarily reflecting a higher year-over-year stock price at the time of the awards ($107.71 in 2017 compared to $67.57 in 2016). Our total compensation in 2017 also included

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equity awarded pursuant to the discretionary vesting component of our performance units awarded in 2013, which were 15% of the 2013 target shares (out of a maximum of 20%), reflecting achievement of the highest return on invested capital in the performance unit peer group and high total shareholder return over that three-year period.

Our compensation structure, objectives and philosophy have largely remained consistent as PCA has sustained outstanding performance over the long term. While we do target certain aspects of our compensation to formulaic performance against pre-determined goals, we also believe that our compensation committee should retain discretion over other elements of compensation, taking into account all relevant business factors to achieve appropriate levels of compensation. In addition to comparison of compensation against market using a peer group, we regularly assess our compensation practices and award forms and structures. We believe that our practices have achieved the right results, with compensation properly tied to company performance. Shareholders have overwhelmingly supported our practices, with our “say-on-pay” vote receiving at least 94% of the vote over each of the last four years, with last year’s say-on-pay vote receiving 94% of the vote. We did not make material changes to our compensation practices in response to the vote.

Comparative Assessments

Consistent with our compensation objectives described above, our executive compensation program is designed to be competitive with the programs that are offered at paper, packaging and related manufacturing companies comparable to us. While comparing our compensation to other companies may not always be totally appropriate due to aspects of our business, these comparisons assist the committee’s decision making process.

At the direction of the committee, we have retained Meridian Compensation Partners, LLC, a nationally recognized compensation consulting firm, to assess the compensation of our named executive officers relative to a group of named executive officers at other peer companies and provide us with information in support of our compensation practices. The assessments include the compilation of compensation data from the peer group companies selected by management and approved by the committee, and the comparison of the compensation of each of our named executive officers relative to similar officers at the peer group companies. Representatives of Meridian and other consultants have not attended meetings of the compensation committee and have not otherwise participated in any compensation decisions or the design of our executive compensation program.

Compensation is compared to a peer group designed to include: (1) direct industry competitors, (2) companies viewed by PCA and its investors as operating in related paper, packaging or container industries and that are comparable in size or scope, across such measures as total revenues, taking into account the integrated nature of PCA’s business, and market capitalization; (3) other companies of similar size and scope in the basic materials

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sector and (4) manufacturing companies of similar size or scope headquartered near the location of PCA’s headquarters. The following companies in the following table were selected for 2017 to be part of the peer group. The composition of the peer group was unchanged from 2015 and 2016.

PCA’s 2017 revenues are slightly above the median of the group, its market capitalization is between the median and 75 ^th percentile of the group and its one-year total stockholder return and its three-year total stockholder return were above the 75 ^th percentile of the group.

In May 2017, Meridian completed a compensation assessment against the peer group, using the most recently filed proxy statements to obtain comparative 2016 compensation data.

The committee uses these assessments to help ensure that our executive compensation is competitive and appropriately reflective of performance. The committee also uses these assessments as a guide when determining each element of incentive compensation, the mix of base salary, annual performance-based, cash incentive awards and equity grants within the overall compensation package, and the total compensation compared to the peer group companies. There is no pre-established policy or target for the mix between cash and non-cash, or short and long-term incentive compensation.

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The committee was generally satisfied with the competitive placement of our officers and, accordingly, did not make competitive adjustments to executive compensation for 2017.

Elements of Compensation

Base Salary

We provide a base salary to attract and retain executive officers and compensate them for their services during the year. Base salary levels are designed to be competitive with peer companies, while taking into account individual experience, performance and accomplishments. Merit-based increases to salaries of named executive officers are generally based on the committee’s assessment of the individual’s performance and are consistent with merit-based increases for the overall salaried employee population. During 2017, base salaries were increased by approximately 3% for each named executive officer.

Annual Cash Incentive Awards

Our annual cash incentive award program is designed to motivate performance in the most important aspects of our business. Target and maximum awards and performance factors to be considered for actual payouts are determined each February at the regularly scheduled compensation committee meeting. Historically, payouts are determined based on consideration of actual performance at or around year end.

Target award levels and maximums are determined based upon our review of competitive information and the importance to our business of, and our expectations for, the individual positions. We place a cap on awards, which in 2017 was 200% of the target award. Our Performance Incentive Plan places an overall maximum on incentive awards at $20,000,000 for all plan participants, which have included our named executive officers. The available pool for annual cash incentive awards for our executive officers is 2% of our EBITDA, subject to the overall plan maximum, as more fully described in note 3 to the Summary Compensation Table. The 2017 target awards were $1,700,000 for Mr. Kowlzan; $1,150,000 for Mr. Hassfurther; $800,000 for Mr. Mundy; $425,000 for Mr. Carter; and $350,000 for Mr. Pflederer. Target awards are established for purposes of determining maximum payouts under the incentive plan, and were increased from prior years to provide appropriate incentives as PCA continues to profitably grow its business, increasing its revenues and overall enterprise value. In practice, we also consider awards made in prior years based upon performance in those years and review performance against those prior years in conjunction with the final determination of awards. Awards made in 2015 and 2016 are disclosed in the Summary Compensation Table and ranged from $545,000 for Mr. Pflederer to $2,500,000 for Mr. Kowlzan in 2016 and from $382,500 for Mr. Pflederer to $2,082,500 for Mr. Kowlzan in 2015.

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Consistent with prior years, the committee established the following performance factors for determination of 2017 awards:

Specific weights are not assigned to each factor, but in a given year, some factors may be deemed more important than others depending on specific circumstances and business conditions for that year. We believe it is important to enable the committee to exercise business judgment and consider uncontrollable or extraneous factors, either positive or negative, in assessing performance and making the awards.

At the end of each year, management prepares and presents to the committee a recommended individual award for each of the named executive officers. In making the recommendation, an analysis of the factors described above is completed, provided and discussed with the committee.

Actual incentive awards for 2017 to the named executive officers averaged 154% of the 2017 target awards. In addition to comparing awards to approved target levels, the committee also compares its current year awards with prior year awards as part of its determination. The committee considered that, for the top five officers,

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awards approximately 6% higher than the 2016 awards for comparable positions were appropriate. In determining the actual awards, the committee considered the following factors:

PCA continued its outstanding performance, benefiting from the execution of its growth strategy through successful acquisitions and internal capital projects. With record earnings, maintenance of the highest margins in its competitive group and continued profitable growth, incentive awards were 6% higher than 2016, a year in which PCA also generated record earnings and significant shareholder value. 2017 awards averaged 154% of incentive plan targets for the executive officers. The factors described above were applied consistently for the executive officers and non-executive management.

Equity Awards

Named executive officers have the opportunity to receive equity awards under our Long-Term Equity Incentive Plan. The purpose of the plan is to promote our long-term growth and profitability by aligning the interests of our executive officers with the interests of our stockholders and by attracting, retaining and rewarding the best available persons for positions of responsibility. Our equity awards have resulted in substantial share ownership by our officers.

In 2017, we made two forms of equity awards to our named executive officers in approximately equal amounts.

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Award levels were determined as follows:

Upon vesting, the ROIC performance units will be paid out in shares of our common stock. The amount paid out is determined based upon our average return on invested capital compared to a peer group consisting of the following companies: AptarGroup, Inc; Bemis Company; Berry Plastics Group, Inc.; Cascades, Inc.; Clearwater Paper Corporation; Crown Holdings, Inc.; Domtar Corporation; PH Glatfelter Co.; Graphic Packaging Holding Company; Greif, Inc.; International Paper Company; KapStone Paper and Packaging Corporation; Owens-Illinois, Inc.; Resolute Forest Products, Inc.; Sealed Air Corporation; Silgan Holdings Inc.; Sonoco Products Co.; and WestRock Company.

The peer group was intended to be a comprehensive group of publicly traded paper and packaging companies, which may compete with us for investor capital. The peer group was the same as the group used for units awarded in 2015 and 2016 and is not intended to be the same group used for comparative assessments as described above under “ — Comparative Assessments.”

Annual return on invested capital for PCA and each peer company will be calculated for 2018, 2019 and 2020 and averaged. Return on invested capital means pre-tax operating profit before publicly reported special items divided by the sum of total debt and total equity.

The units will vest on June 21, 2021, the fourth anniversary of the date of the award, as long as the recipient is employed by, or otherwise provides services to, PCA. If PCA performs in the top quartile of the group, a number of shares equal to 100% of the units will be paid out with the committee having discretion to award up to an additional 20%. If PCA performs in the second quartile of the group, 80% of the units will be paid out, with the committee having discretion to award up to an additional 20%. If PCA performs in the third quartile of the group, 40% of the units will be paid out, with the committee having the discretion to award an additional 40%. If PCA performs in the fourth quartile, there is no payout. The committee may consider factors it determines to be appropriate in connection with the discretionary vesting, including ranking within the quartile and business conditions that drove performance during the period.

Annual awards are made to the named executive officers on the same date as other plan participants. Historically, the grant date has been between June 12th and July 2nd of each year. We have chosen to pay cash incentive awards at the beginning of the year, and to make equity grants near mid-year. This timing gives us an opportunity to discuss with the named executive officers and other key managers their compensation and

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performance twice per year, instead of once per year, which reinforces our philosophy to them that our compensation plans are based on pay-for-performance.

Prior Year Awards

The performance period for the performance units awarded in 2013 ended on December 31, 2016. PCA achieved top quartile performance, resulting in 100% of the units being earned. Under the terms of the performance units described above, with top quartile vesting, the committee retained the discretion to award an additional 20% of the target shares at or around the time of the vesting of those units on June 24, 2017, considering factors that it determined to be appropriate. As PCA was the top ranked company in the peer group on the ROIC measure, and generated a total shareholder return of 46.3% over the three-year period ending December 31, 2016, which was second highest in the ROIC performance group, the committee determined to award an additional 15% of the target shares to each named executive officer. Under applicable reporting rules, the value of those shares on June 24, 2017 are reported as 2017 compensation in the summary compensation table.

The performance period for the performance units awarded in 2014 ended on December 31, 2017. PCA achieved top quartile performance, resulting in 100% of the units being earned, subject to continued service through June 23, 2018, the vesting date. The number of shares earned by each named executive officer is as follows: Mr. Kowlzan, 18,963 shares; Mr. Hassfurther, 15,100 shares; Mr. Carter, 2,634 shares and Mr. Pflederer, 2,809 shares, plus, in all cases, shares with a value equal to all dividends declared on the shares earned. The committee has the discretion to award up to 20% of the target shares on or around the vesting date and will make such determination later in 2018.

Defined Benefit Retirement Plans

Effective May 1, 2004, we adopted a grandfathered pension plan for certain salaried employees (the “PCA Pension Plan”), including Mr. Kowlzan and Mr. Hassfurther, each of whom previously had participated in the pension plan of our former parent company, Pactiv Corporation. During the period from April 12, 1999, when we became a stand-alone company, through April 30, 2004, PCA eligible salaried employees, including Mr. Kowlzan and Mr. Hassfurther, were allowed to continue to participate in the Pactiv pension plans and Pactiv’s supplemental executive retirement plan, for an agreed upon fee paid by us to Pactiv. The benefit formula for the PCA Pension Plan is comparable to that of the Pactiv pension plan except that the PCA Pension Plan uses career average base pay in the benefit formula in lieu of final average base pay. The PCA Pension Plan recognizes service earned under both the new PCA Pension Plan and the prior Pactiv pension plan. Benefits earned under the PCA Pension Plan are reduced by retirement benefits earned under the Pactiv pension plan through April 30, 2004. All assets and liabilities associated with benefits earned through April 30, 2004 for our salaried employees and retirees were retained by the Pactiv pension plan.

In addition to the PCA Pension Plan, Mr. Kowlzan and Mr. Hassfurther participate in a PCA supplemental executive retirement plan (the “SERP”). Benefits are determined using the same formula as the PCA Pension Plan but in addition to counting career average base pay, the SERP also recognizes incentive awards and any pay earned in excess of IRS qualified plan compensation limits. Benefits earned under the SERP are reduced by benefits paid from the PCA Pension Plan and any prior qualified pension and SERP benefits earned under the Pactiv pension plan.

Mr. Mundy, Mr. Carter and Mr. Pflederer do not receive any pension benefits because they joined PCA after April 12, 1999.

401(k) Plan

We offer a defined contribution 401(k) plan to our salaried employees, including the named executive officers. We have historically provided to PCA employees a company matching contribution of up to 5.2% of

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participant contributions and a company retirement contribution for employees not eligible to participate in our defined benefit pension plan, including Mr. Mundy, Mr. Carter and Mr. Pflederer. For certain highly compensated salaried employees including the named executive officers, who make the maximum contribution to the plan permitted by tax regulations, we provide an extended match program under which the equivalent amount of the suspended company matching contribution is paid directly to the employee in the form of supplemental, taxable compensation.

Deferred Compensation Plan

We provide a voluntary non-qualified deferred compensation plan for eligible officers, including the named executive officers. Certain officers not eligible to participate in the defined benefit pension plan, including Mr. Mundy, Mr. Carter and Mr. Pflederer, receive an annual contribution to the deferred compensation plan in lieu of pension benefits.

Perquisites

Other than club memberships for officers and key management with sales responsibilities, including Mr. Hassfurther, we do not provide perquisites.

Health and Welfare Benefits

The named executive officers are offered health coverage, life and disability insurance under the same programs as all other salaried employees.

Potential Payments Upon Termination or a Change of Control

Changes in employment status such as termination, death or disability, a change of control or retirement can trigger a benefit or accelerate a benefit for our salaried employees, including the named executive officers. These payments are described below. Named executive officers are not entitled to receive any incremental benefits or accelerated benefits that are different in scope, terms or operation than what are generally available to our salaried employees who are eligible to participate in our various compensation plans. However, the committee will consider post-retirement or post-termination arrangements and acceleration of certain equity awards for named executive officers on a case-by-case basis.

Payments Made Upon Termination

In general, when a named executive officer terminates employment with us, other than a termination for cause, the named executive officer is entitled to receive the amounts they have earned during the term of their employment and any benefits allowed as part of our compensation plans. These amounts that they will receive include the following:

Payments Made Upon Death or Disability

In the event of the death or disability of a named executive officer, in addition to the items identified above, all named executive officers will receive benefits under our disability plan or payments under our life insurance plan, as appropriate. Under our equity incentive plan, upon death or disability, generally all restrictions on restricted stock will lapse and performance units will be paid out at 100%.

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Payments Made Upon a Change In Control

There are no employment agreements for any named executive officers, nor are we contractually obligated to make any type of cash payment to any named executive officer in the event of a change of control. In connection with a change of control, restricted stock awarded before 2016 immediately vests and performance units awarded before 2016 immediately vest and are paid out at 100%. We adopted double trigger a change of control provisions for restricted stock and performance units awarded in 2016 and 2017. If a substitute equity award meeting certain conditions is provided to the executive officer in connection with a change of control, that award will not vest as a result of the change of control unless the officer’s employment is terminated or the officer resigns for good reason within two years after a change of control. “Good reason” includes breach of certain obligations by the company, diminution of duties or authority of the officer, certain reductions of compensation of the officer or relocation of the principal office where the officer works.

Based on the closing market price of our common stock of $120.55 on the New York Stock Exchange on December 31, 2017, the value of unvested restricted stock and performance units held by each named executive officer that would vest immediately upon a change of control, and, in the case of awards made in 2016 or 2017, if the officer was terminated or resigned for good reason within two years after such change in control was: Mr. Kowlzan, $23,486,587; Mr. Hassfurther, $16,562,797; Mr. Mundy, $4,425,531; Mr. Carter, $4,520,187; and Mr. Pflederer, $3,189,706.

Severance Benefits

We have no contractual obligation to pay severance to any of our named executive officers in the event of a termination. Any severance payments made to our named executive officers would be considered on a case-by-case basis, and any payment of severance that might be deemed appropriate would require approval of the committee. The committee will assess post-retirement arrangements with retiring named executive officers on a case-by-case basis, taking into account transitional needs, expertise needed, customer relationships, the company’s succession plans and other factors, such as non-competition and non-solicitation covenants, that the committee determines to be important.

Tax Implications

The committee has considered the provisions of Code Section 162(m), which generally limits the annual tax deductibility of compensation paid to each named executive officer to $1 million. To the extent possible, the committee intends to preserve the federal income tax deductibility, but may choose to provide compensation that may not be deductible if it believes that such payments are appropriate to ensure that our named executive officers receive total compensation that is competitive with our peer group, reflects superior performance or otherwise achieves our compensation objectives, such as the motivation and retention of our executive officers. The Code Section 162(m) performance factors and annual grant limitations under the Performance Incentive Plan and Long-Term Equity Incentive Plan are intended to enable us to provide incentive compensation to certain of our executive officers in a manner that qualifies for an exemption, as “performance-based compensation”, from the deduction limitations under Section 162(m). As recent tax legislation has eliminated the ability to deduct “performance based compensation” in 2018 and beyond, our ability to deduct “performance based compensation” will be limited to certain compensation awarded prior to the end of 2017 to the extent permitted by the transition rules included in such legislation.

Policies Applicable to Executive Officers

Trading in Our Stock

Our trading policy prohibits our directors and executive officers from participating in short-swing trading, short selling or entering into any derivative securities related to their ownership of our common stock or pledging our stock. All transactions in PCA common stock by our directors and executive officers are subject to trading

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window periods and additionally must be pre-cleared by our chief executive officer and our general counsel to ensure compliance with applicable securities laws.

Compensation Recovery Policy

We have an executive compensation recovery policy, which relates to the recoupment of any bonus, equity-based award or other compensation given to a current or former corporate officer, as defined in the policy, in the event of a restatement of the company’s reported financial results. The named executive officers are included within this policy. If the compensation committee determines that any compensation was made to one of the covered officers based on later restated financial statements, the committee may adjust such compensation within 60 months of the restatement, and may seek to recover the part of any compensation that was paid based upon the financial performance in the reported financial statements that were restated. If the individual fails to repay any amount required under this policy, the committee may pursue appropriate legal remedies to recoup such amount. The committee may set-off the amount owed against any amount or award that would otherwise be granted to the individual or reduce any future compensation or benefit to such individual. The compensation committee will revise the policy consistent with regulations under the Dodd-Frank Act once those regulations are final.

Share Ownership Guidelines

We maintain stock ownership guidelines that apply to all of our directors and our executive officers. The individual guidelines are owning stock having a value equal to or greater than:

Non-management directors must hold stock having a value equal to at least $200,000.

The committee may, from time to time, temporarily suspend or reevaluate and revise participants’ guidelines to give effect to changes in our common stock price or other factors the committee deems relevant. Shares that count towards satisfaction of the guidelines include: (1) shares owned outright by the participant or an immediate family member that shares the same household; (2) shares held in our defined contribution plans; and (3) restricted stock or restricted stock units issued by us, whether or not vested. Shares underlying option awards and performance units (prior to certification of achievement of the performance goals) do not count toward achievement of the share ownership guidelines.

Participants are required to achieve their guideline within five years of becoming subject to the guidelines. The committee has the authority to review each participant’s compliance (or progress towards compliance) with the guidelines from time to time. In its discretion, the committee may impose conditions, restrictions or limitations on any non-compliant participant as the committee determines to be necessary or appropriate.

All of our non-management directors and named executive officers are in compliance with, or are achieving adequate progress towards, the guidelines.

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