SKYW SkyWest Inc

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SECURITIES AND EXCHANGE COMMISSION

Washington, D.C. 20549

FORM 11-K

FOR ANNUAL REPORTS OF EMPLOYEE STOCK

REPURCHASE SAVINGS AND SIMILAR PLANS

PURSUANT TO SECTION 15(d) OF THE

SECURITIES EXCHANGE ACT OF 1934

x                               ANNUAL REPORT PURSUANT TO SECTION 15(d) OF THE SECURITIES EXCHANGE ACT OF 1934

for the year ended December 31, 2016

or

o                                  TRANSITION REPORT PURSUANT TO SECTION 15 (d) OF THE SECURITIES EXCHANGE ACT OF 1934

For the transition period from                             to                             

Commission File No. 000-14719

ATLANTIC SOUTHEAST AIRLINES, INC. INVESTMENT SAVINGS PLAN

(Full title of the plan)

SKYWEST, INC.

444 South River Road

St. George, Utah 84790

(Name of issuer of the securities held pursuant to the

plan and the address of its principal executive office)

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Atlantic Southeast Airlines, Inc. Investment Savings Plan

I ndex to Financial Statements and Supplemental Schedule

*Other supplemental schedules required by section 2520-103.10 of the Department of Labor’s Rules and Regulations for Reporting and Disclosure under the Employee Retirement Income Security Act of 1974 have been omitted because they are not applicable.

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See accompanying notes to financial statements.

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See accompanying notes to financial statements.

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ATLANTIC SOUTHEAST AIRLINES, INC. INVESTMENT SAVINGS PLAN

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Plan Termination

Under the provisions of the Plan, the Company reserves the right to amend or terminate the Plan at any time in accordance with the provisions of ERISA, provided that amendments will not divert a vested interest or permit any part of the funds to revert to the Company or to be used for any purpose other than for the exclusive benefit of participants or their beneficiaries.  If the Plan is terminated, each participant’s account will become fully vested.

Notes Receivable from Participants

Participants may borrow a minimum of $1,000 up to a maximum of the lesser of $50,000 or 50% of their vested account balances.  Loan terms range from one to five years.  Loans are secured by the vested balance in the participant’s account and bear interest at a rate commensurate with local prevailing rates as determined at the time of the loan.

Forfeitures

Forfeitures of terminated participants’ nonvested accounts are used to reduce future matching contributions of the Company. The forfeitures account had a balance of approximately $19 and $108,000 as of December 31, 2016 and 2015, respectively.

2. Summary of Significant Accounting Policies

Basis of Presentation

The Plan’s financial statements have been prepared on the accrual basis of accounting in accordance with accounting principles generally accepted in the United States of America (“U.S. GAAP”).

Risks and Uncertainties

The Plan provides for investments in securities that are exposed to various risks, such as interest rate, currency exchange rate, credit and overall market fluctuation.  Due to the level of risk associated with certain investment securities, it is reasonably possible that changes in the values of investment securities will occur in the near term and that such changes could materially affect participants’ account balances and the amounts reported in the statements of assets available for benefits.

Valuation of Investments and Income Recognition

Mutual funds are valued at quoted market prices, which represent the net asset values of units held by the Plan at year-end.  Units of the Company’s common stock fund and stable value funds are valued using the net asset value, which approximates fair value, on the last business day of the Plan year.  Unrealized appreciation or depreciation caused by fluctuations in the market value of investments is recognized in the statement of changes in assets available for benefits.  Dividends and interest are reinvested as earned.  Purchases and sales of investments are recorded on a trade-date basis.

Payment of Benefits

Benefits are recorded when paid by the Plan.

Notes Receivable from Participants

Notes receivable from participants represent participant loans that are recorded at their unpaid principal balance plus any accrued but unpaid interest. Interest income on notes receivable from participants is recorded when it is earned. Related fees are recorded as administrative expenses and are expensed when they are incurred. No allowance for credit losses has been recorded as of December 31, 2016 or 2015. If a participant ceases to make loan repayments and the Plan Administrators deem the participant loan to be a distribution, the participant loan balance is reduced and a benefit payment is recorded.

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Administrative Expenses

The Plan pays substantially all administrative expenses of the Plan.

Use of Estimates

The preparation of financial statements in conformity with U.S. GAAP requires management to make estimates and assumptions that affect certain reported amounts of assets available for benefits at the date of the financial statements, the changes in assets available for benefits during the reporting period, and, when applicable, the disclosure of contingent assets and liabilities at the date of the financial statements.  Actual results could differ from those estimates.

Recently Issued Accounting Standards Update

In May 2015, the Financial Accounting Standards Board (“FASB”) issued Accounting Standards Update (“ASU”) No. 2015-07, Fair Value Measurement (Topic 820): Disclosures for Investments in Certain Entities That Calculate Net Asset Value per Share (or Its Equivalent) , which requires that an investment for which fair value is measured using the net asset value per share practical expedient be removed from the fair value hierarchy in all periods presented in a plan’s financial statements. This guidance is effective for fiscal years beginning after December 15, 2015, and must be retrospectively applied. The Plan adopted this guidance as of January 1, 2016, removing the Company’s common stock fund and stable value funds from the fair value hierarchy, which did not have a material impact on the Plan’s financial statements.

In July 2015, the FASB issued ASU No. 2015-12,  Plan Accounting: Defined Benefit Pension Plans (Topic 960), Defined Contribution Pension Plans (Topic 962), Health and Welfare Benefit Plans (Topic 965): (Part I) Fully Benefit-Responsive Investment Contracts, (Part II) Plan Investment Disclosures, (Part III) Measurement Date Practical Expedient . ASU 2015-12 Part I designates contract value as the only required measure for fully benefit-responsive investment contracts. ASU 2015-12 Part II simplifies the investment disclosure requirements under existing U.S. GAAP, including eliminating the disclosure of (1) individual investments that represent 5 percent or more of net assets available for benefits and (2) the net appreciation or depreciation for investments by general type. The Plan adopted this guidance as of January 1, 2016 and separately presented the Company’s common stock fund and stable value funds from other assets in the Statements of Assets Available for Benefits as of December 31, 2016 and 2015 and modified certain disclosures in the notes to financial statements.  The Plan also eliminated the disclosure of individual investments that represent 5 percent or more of assets available for benefits and the net appreciation or depreciation for investments by general type.

Management believes the adoption of this guidance reduces unnecessary complexity in the financial statements and improves the usefulness of the information provided to users of these financial statements.

Subsequent Events

The Plan Administrators have evaluated events occurring subsequent to December 31, 2016 through the date of issuance of these financial statements.

3.  Fair Value Measurements

U.S. GAAP defines fair value as the price that would be received to sell an asset or paid to transfer a liability (an exit price) in an orderly transaction between market participants at the measurement date.  U.S. GAAP establishes a fair value hierarchy that requires an entity to maximize the use of observable inputs when measuring fair value, with the following three levels of inputs:

Level 1 — Valuation is based upon quoted prices in active markets for identical securities.

Level 2 — Valuation is based upon other significant observable inputs that reflect the assumptions market participants would use in pricing the asset developed on market data obtained from sources independent of the Plan.

Level 3 — Valuation is based upon unobservable inputs that reflect the assumptions that Plan management believes market participants would use in pricing the asset, based on the best information available.

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3.  Fair Value Measurements (Continued)

As of December 31, 2016 and 2015, the Plan held certain assets that are required to be measured at fair value on a recurring basis. Assets measured at fair value on a recurring basis are summarized below (in thousands):

* The fair values for the stable value funds and common stock fund are provided above to permit reconciliation of the fair value hierarchy to the amounts presented in the statements of assets available for benefits.  In accordance with ASU 2015-12, the stable value funds and the common stock fund are measured using the net asset value per unit as a practical expedient and therefore are not classified in the fair value hierarchy.  Prior year amounts have been retrospectively adjusted for consistency with this presentation as required upon the adoption of ASU 2015-07 and ASU 2015-12.

The SkyWest, Inc. Common Stock Fund (the “Common Stock Fund”), the JP Morgan Stable Asset Income Fund, and the T. Rowe Price Stable Value (the “Stable Value Funds”) are valued at the net asset value (NAV) of units of the respective funds. The NAV, as provided by the respective fund trustees, is used as a practical expedient to estimating fair value. The NAV is based on the fair value of the underlying investments held by the fund less its liabilities. This practical expedient is not used when it is determined to be probable that the fund will sell the investment for an amount different than the reported NAV.

The Stable Value Funds are designed to provide safety of principal with consistency of returns with minimal volatility by employing a strategy of investing in investment contracts and security-backed contracts while employing broad diversification among contract issuers and underlying securities. The Plan Sponsor is able to redeem the investment in the Stable Value Funds by providing a 12-month notice. Although the notice requirement is 12 months, JP Morgan and T. Rowe Price have indicated the ability to redeem the investment sooner.  Redemption frequency for the Stable Value Funds is immediate, and the Stable Value Funds contain no unfunded commitments. There are no other significant restrictions on the ability to redeem the investment.

The Common Stock Fund includes investments in SkyWest, Inc. common stock. Redemption frequency for the Common Stock Fund is immediate, the Common Stock Fund contains no unfunded commitments, and has no redemption restrictions.

4.  Party-in-Interest Transactions

ExpressJet Airlines, Inc. is a wholly owned subsidiary of SkyWest, Inc.  SkyWest, Inc. common stock is offered as an investment option in the Plan.  Transactions associated with the shares of common stock of SkyWest, Inc. are considered exempt party-in-interest transactions.  The Plan held 250,277 and 139,853 shares of SkyWest, Inc. common stock with a fair value of $3,145,398 and $2,660,011 as of December 31, 2016 and 2015, respectively.

Plan investments included mutual funds and a collective trust fund managed by JPMorgan, the Plan trustee until July 29, 2016, and therefore were party-in-interest transactions.  While transactions involving Plan assets with a party-in-interest may be prohibited, these transactions are exempt under ERISA Section 408(b)(8).

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Notes receivable from participants totaling $6,107,488 and $6,707,889 as of December 31, 2016 and 2015, respectively, are also considered exempt party-in-interest transactions.

5.  Income Tax Status

The Plan has received a determination letter from the Internal Revenue Service dated October 4, 2016, stating that the Plan and related trust are designed in accordance with applicable sections of the IRC and, therefore, the related trust is exempt from taxation.  The Plan is required to operate in conformity with the IRC to maintain its qualification.  Although the Plan has been amended since receiving the determination letter, the Plan Administrators believe the Plan is being operated in compliance with the applicable requirements of the IRC and, therefore, believe that the Plan, as amended, is qualified and the related trust is tax exempt.

6 .  Plan Amendments

Effective August 1, 2016, the Plan was restated under the Wells Fargo Bank, N.A. Defined Contribution Volume Submitter Plan and Trust and incorporated all previous amendments.  The restated Plan was subsequently amended to permit transfer of a non-Roth account to a Roth account.

7 .  Reconciliation of Financial Statements to Form 5500

The following is a reconciliation of assets available for benefits as reported in the financial statements as of December 31, 2016 and 2015 to the Form 5500:

The following difference between the financial statements and the Form 5500 is due to the adjustment from fair value to contract value of the stable value funds for the year ended December 31, 2016:

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Supplemental Schedule

ATLANTIC SOUTHEAST AIRLINES, INC. INVESTMENT SAVINGS PLAN

EIN:  58-1354495    Plan No.:  001

Form 5500, Schedule H, Part IV, Line 4i

* Indicates a party-in-interest to the Plan.

Column (d), cost information, is not applicable for participant-directed investments.

See accompanying Report of Independent Registered Public Accounting Firm .

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