UNITED STATES

SECURITIES AND EXCHANGE COMMISSION

WASHINGTON, D.C. 20549

FORM 11-K

For the fiscal year ended December 31, 2018

For the Transition Period From                  to                 

Commission File Number 001-37845

MICROSOFT CORPORATION SAVINGS PLUS 401(k) PLAN

Microsoft Corporation

One Microsoft Way

Redmond, Washington 98052-6399

REQUIRED INFORMATION

The Microsoft Corporation Savings Plus 401(k) Plan (the “Plan”) is subject to the Employee Retirement Income Security Act of 1974 (“ERISA”). Therefore, in lieu of the required information outlined as Items 1-3 of the Form 11-K, the statements of net assets available for benefits and the related statements of changes in net assets available for benefits as of and for the years ended December 31, 2018 and 2017, which have been prepared in accordance with the financial reporting requirements of ERISA, are attached hereto as Appendix 1 and incorporated herein by this reference.

SIGNATURES

The Plan.    Pursuant to the requirements of the Securities Exchange Act of 1934, the trustees (or other persons who administer the employee benefit plan) have duly caused this annual report on Form 11-K to be signed on its behalf by the undersigned hereunto duly authorized.

APPENDIX 1

MICROSOFT CORPORATION

SAVINGS PLUS 401(k) PLAN

REPORT OF INDEPENDENT REGISTERED PUBLIC ACCOUNTING FIRM;

FINANCIAL STATEMENTS AS OF AND FOR THE YEARS ENDED DECEMBER 31, 2018 AND 2017;

NOTES TO FINANCIAL STATEMENTS; AND

SUPPLEMENTAL SCHEDULE OF ASSETS (HELD AT END OF YEAR) AS OF DECEMBER 31, 2018

MICROSOFT CORPORATION

SAVINGS PLUS 401(k) PLAN

TABLE OF CONTENTS

REPORT OF INDEPENDENT REGISTERED PUBLIC ACCOUNTING FIRM

To the Participants and Administrators of the Microsoft Corporation Savings Plus 401(k) Plan

Redmond, WA

Opinion on the Financial Statements

We have audited the accompanying statements of net assets available for benefits of the Microsoft Corporation Savings Plus 401(k) Plan (the “Plan”) as of December 31, 2018 and 2017, the related statements of changes in net assets available for benefits for the years then ended, and the related notes (collectively referred to as the “financial statements”). In our opinion, the financial statements present fairly, in all material respects, the net assets available for benefits of the Plan as of December 31, 2018 and 2017, and the changes in net assets available for benefits for the years then ended, in conformity with accounting principles generally accepted in the United States of America.

Basis for Opinion

These financial statements are the responsibility of the Plan’s management. Our responsibility is to express an opinion on the Plan’s financial statements based on our audits. We are a public accounting firm registered with the Public Company Accounting Oversight Board (United States) (PCAOB) and are required to be independent with respect to the Plan in accordance with the U.S. federal securities laws and the applicable rules and regulations of the Securities and Exchange Commission and the PCAOB.

We conducted our audits in accordance with the standards of the PCAOB. Those standards require that we plan and perform the audit to obtain reasonable assurance about whether the financial statements are free of material misstatement, whether due to error or fraud. Our audits included performing procedures to assess the risks of material misstatement of the financial statements, whether due to error or fraud, and performing procedures that respond to those risks. Such procedures included examining, on a test basis, evidence regarding the amounts and disclosures in the financial statements. Our audits also included evaluating the accounting principles used and significant estimates made by management, as well as evaluating the overall presentation of the financial statements. We believe that our audits provide a reasonable basis for our opinion.

Report on Supplemental Schedule

The supplemental schedule of assets (held at end of year) as of December 31, 2018 has been subjected to audit procedures performed in conjunction with the audit of the Plan’s financial statements. The supplemental schedule is the responsibility of the Plan’s management. Our audit procedures included determining whether the supplemental schedule reconciles to the financial statements or the underlying accounting and other records, as applicable, and performing procedures to test the completeness and accuracy of the information presented in the supplemental schedule. In forming our opinion on the supplemental schedule, we evaluated whether the supplemental schedule, including its form and content, is presented in compliance with the Department of Labor’s Rules and Regulations for Reporting and Disclosure under the Employee Retirement Income Security Act of 1974. In our opinion, such schedule is fairly stated, in all material respects, in relation to the financial statements as a whole.

/S/ DELOITTE & TOUCHE LLP

Seattle, Washington

June 13, 2019

We have served as the auditor of the Plan since 1987.

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STATEMENTS OF NET ASSETS AVAILABLE FOR BENEFITS

Refer to accompanying notes.

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STATEMENTS OF CHANGES IN NET ASSETS AVAILABLE FOR BENEFITS

Refer to accompanying notes.

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NOTES TO FINANCIAL STATEMENTS

NOTE 1 — DESCRIPTION OF THE PLAN AND ACCOUNTING POLICIES

Plan Description

The Microsoft Corporation Savings Plus 401(k) Plan (the “Plan”), a defined contribution plan, is sponsored by Microsoft Corporation (the “Company” or “Microsoft”). Participating employers included in the Plan are Microsoft Corporation; MOL Corporation; Vexcel Corporation; Microsoft Online, Inc; Microsoft Payments, Inc; Microsoft Open Technologies, Inc; and Microsoft Technology Licensing. These entities represent Microsoft or wholly owned subsidiaries of Microsoft. The Plan year is January 1 through December 31. The Plan is administered by the 401(k) Administrative Committee (the “Plan Administrator”) and subject to the provisions of the Employee Retirement Income Security Act of 1974 (“ERISA”). The information below summarizes certain aspects of the Plan as in effect during 2018 and 2017, and is intended to be a summary only. Plan participants should refer to the Summary Plan Description for more complete information.

Accounting Principles

The financial statements and accompanying notes are prepared in accordance with accounting principles generally accepted in the United States of America (“GAAP”).

Eligibility

Regular and retail services employees of participating employers who are on U.S. payroll and have reached age 18 may enroll in the Plan at any time.    

Eligible Compensation

Eligible compensation includes wages, salary, bonuses, commissions, and overtime. Compensation does not include, for example, items such as stock awards, amounts realized on the exercise of stock options, reimbursements or other expense allowances, fringe benefits (cash and noncash), moving expenses, deferred compensation, welfare plan benefits including health or life insurance, or bonuses or expense allowances which are not based upon performance as an employee.

Contributions

Participant Contributions

Participants may contribute to the Plan on a pre-tax and/or Roth basis using eligible compensation each pay period, subject to statutory and regulatory limitations. Participants reaching age 50 or older by the end of the Plan year may also elect to make additional catch-up contributions to the Plan on a pre-tax and/or Roth basis. Additionally, participants could contribute up to $27,250 for 2018 and $20,000 for 2017 on an after-tax basis. A participant’s aggregate contribution election (combined pre-tax, Roth, pre-tax catch-up, Roth catch-up, and after-tax) generally may not exceed 65 percent of his or her eligible compensation per pay period. Participants may elect to suspend or reinstate their contributions at any time.

Participants may also choose to make rollover contributions to the Plan of amounts received from an eligible employer plan maintained by another company, including direct rollovers from such plans. Effective April 17, 2017, participants may also make rollover contributions to the plan from an individual retirement account or annuity described in Internal Revenue Code (“IRC”) Section 408(a) or 408(b) that is eligible to be rolled over and would otherwise be includible in gross income.

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Employer Contributions

The Company provides participants with a matching contribution on eligible pre-tax and/or Roth contributions of $0.50 for every $1.00 contributed. The matching contribution is provided for up to 50 percent of the maximum annual 401(k) pre-tax and Roth contribution limit of $18,500 and $18,000 for 2018 and 2017, respectively. Participants do not receive a match on after-tax contributions.

Transfers

The Company acquired TouchType Ltd. in 2016 and the TouchType Inc. 401k plan assets merged into the Plan during 2017. The merged assets are included as transfers in the statement of changes in net assets available for benefits for the Plan year ended December 31, 2017. There were no plan mergers for the year ended December 31, 2018.

Employee Stock Ownership Plan Feature

The Plan includes an Employee Stock Ownership Plan (“ESOP”) feature for the portion of the Plan designed to invest primarily in Microsoft Common Stock. The ESOP feature allows participants to either reinvest their cash dividends earned on Microsoft Common Stock or receive those dividends in cash. Amounts invested in Microsoft Common Stock are treated as being held through the ESOP, provided that at the time such amounts were received by the Plan (e.g., through contributions or transfers), the participants whose Plan accounts received such assets were employed by Microsoft or a corporation that is part of the same controlled group of corporations as Microsoft.

Participants who are not employed by an employer established as a corporation that is part of the same controlled group of corporations as Microsoft may not participate in the ESOP, but may have their Plan accounts invested in Microsoft Common Stock to the same extent as other participants. However, such participants that are not eligible to participate in the ESOP feature are not eligible to receive dividends on Microsoft Common Stock in cash paid directly to them. Instead, dividends paid on amounts they have invested in Microsoft Common Stock will automatically be reinvested in Microsoft Common Stock.

Effective January 1, 2016, the investment of new contributions or transfer of existing account holdings into Microsoft Common Stock within the Plan was discontinued. Participant accounts with existing Microsoft Common Stock can retain those holdings, and dividends on Microsoft Common Stock can continue to be reinvested or received in cash.

Participant Accounts

Each participant’s account is credited with (a) participant contributions and employer contributions, and (b) the allocation of Plan earnings and expenses, based on participant earnings or account balances, as defined. The benefit to which a participant is entitled is the benefit that can be provided from the participant’s vested account. All amounts in participant accounts are participant-directed. Participants may invest in various instruments including mutual funds, common collective trusts, and separately managed accounts. Participants also have the option to direct their investments through a brokerage account.

Vesting

Participants are fully vested in Plan accounts at all times.

Distributions

Active participants may take a withdrawal from the Plan in the event of a financial hardship. A hardship withdrawal is limited to the amount necessary to meet the participant’s immediate financial need, and further limited to pre-tax contributions, after-tax contributions, pre-tax catch-up contributions, and rollover contributions (excluding rollover contributions attributable to designated Roth contributions, Roth in-plan conversion amounts and earnings thereon, and acquisition rollovers). In 2017 and 2018, a hardship withdrawal generally resulted in a six-month

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suspension of contributions (other than rollover contributions) to the Plan. Active participants may also take a withdrawal from their rollover and after-tax account types within the Plan without meeting one of the hardship criteria.

After reaching age 59¹⁄₂, active participants may withdraw all, or any portion, of the balance in their accounts. Distributions, in full or any portion, may also occur if the participant terminates employment, retires, becomes permanently disabled, or dies. Distributions of investments in Microsoft Common Stock may be taken in the form of Microsoft Common Stock or cash. Distributions may be made in installments.

Effective January 1, 2019, the Plan was amended to adopt certain provisions of the Bipartisan Budget Act of 2018. With this amendment, the six-month suspension of contributions following a hardship withdrawal was eliminated, and the sources available for a hardship withdrawal were expanded to include earnings on pre-tax (including catch-up) and after-tax contributions starting in January 2019.

In-Plan Roth Conversions

Active participants may convert their Plan distribution-eligible balances to their Roth account within the Plan.

Administrative Expenses

Plan administrative expenses are paid by the Company to the extent not paid or offset by the Plan. Participants are responsible for fees associated with certain transactions or services they utilize, such as loan originations and maintenance, domestic relations order qualifications, dividend check processing, overnight check fees, and professional management service fees. Participants also pay commission charges to Fidelity for buying and selling Microsoft Common Stock within the Plan.

Plan Amendment and Termination

The Company has the right to amend or terminate the Plan. If the Plan is terminated, all account balances will be distributed in the form and manner determined by the Plan Administrator.

Risks and Uncertainties

The Plan utilizes various investment instruments, including common stock, mutual funds, common collective trusts, and separately managed accounts. Investment securities, in general, are exposed to various risks, such as interest rate risk, credit risk, and overall market volatility. 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 the amounts reported in the financial statements.

Estimates and Assumptions

The preparation of financial statements in conformity with GAAP requires management to make estimates and assumptions that affect the reported amounts of assets and liabilities and changes therein. Actual results and outcomes may differ from management’s estimates and assumptions. The Plan has no contingent assets or liabilities for any periods presented in these financial statements.

Valuation of Investments and Income (Loss) Recognition

Investments are recorded at fair value. Security transactions are accounted for as of the trade date. Dividend income is recorded on the ex-dividend date, and interest income is recorded as earned. Net increase (decrease) in fair value of investments includes the Plan’s gains and losses on investments bought and sold as well as held during the year.

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Participant Loans

Participant loans are measured at their unpaid principal balance plus any accrued but unpaid interest, and participant loans deemed distributed due to default are included in benefits paid to participants on the statements of changes in net assets available for benefits.

Other Receivables and Payables

Other receivables and payables as of December 31, 2018 and 2017 primarily consisted of unsettled trades. Other receivables also included accrued interest.

NOTE 2 — FINANCIAL INSTRUMENTS

The Plan accounts for certain assets and liabilities at fair value. The hierarchy below lists three levels of fair value based on the extent to which inputs used in measuring fair value are observable in the market. The Plan categorizes each of its fair value measurements in one of these three levels based on the lowest level input that is significant to the fair value measurement in its entirety. These levels are:

Mutual funds are valued at the closing price as reported by the fund. Common stocks are valued at the closing price reported on the active markets on which the individual securities are traded.

Common collective trusts are valued using the Net Asset Value (“NAV”) provided by the trustee in order to estimate fair value. The NAV is based on the fair value of the underlying investments held by the fund less its liabilities. In the event the Plan were to initiate a full redemption of a common collective trust, the investment advisor reserves the right to temporarily delay withdrawal from the common collective trust in order to ensure that securities liquidations will be carried out in an orderly business manner. The common collective trusts have no unfunded commitments, other redemption restrictions, or redemption notice periods. The portfolios are comprised of a mix of stocks, bonds, commodities, and cash.

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Financial Instruments Measured at Fair Value

The significance of transfers between levels is evaluated based upon the nature of the financial instrument and the size of the transfer relative to total net assets available for benefits. No significant transfers occurred between Level 1 and Level 2 for the years ended December 31, 2018 and 2017.

NOTE 3 — DERIVATIVES

Investment managers acting under the Plan use derivative instruments to manage risks related to foreign currencies and interest rates, to enhance investment returns for the Plan, and to facilitate Plan portfolio diversification. The Plan’s derivatives consisted of over-the-counter foreign exchange forward contracts and exchange-traded futures contracts, as well as put and call options, for which no hedge accounting treatment is applied. The related notional amounts, gross fair values, and amounts recognized in earnings were immaterial as of and for the years ended December 31, 2018 and 2017. These derivative instruments are a component of the “Other” caption of separately managed accounts in Note 2—Financial Instruments.

NOTE 4 — PARTICIPANT LOANS

Participant loans are available in $100 increments ranging from $1,000 to $50,000. The maximum loan amount is the lesser of (a) 50 percent of the vested account balance, reduced by the current outstanding balance of all other loans from the Plan; or (b) $50,000, reduced by: (1) the current outstanding balance of all other loans from the Plan, and (2) the excess (if any) of all Plan loans during the previous 12 months over the current outstanding balance of Plan loans. When determining the maximum loan amount available under the Plan, outstanding loan balances under any subsidiary and affiliate Microsoft retirement plans are considered in conjunction with the Plan. Participants are limited to two loans—one Primary Residence Loan and one General Loan. The term of a Primary

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Residence Loan may not exceed 15 years (or 30 years for Nokia Plan legacy loans) or be less than 12 months. The term of a General Loan may not exceed five years (or 15 years for Nokia Plan legacy loans) or be less than 12 months.

The interest rate for participant loans is 1 percent plus the prime rate on corporate loans. The range of interest rates for outstanding Primary Residence Loans as of December 31, 2018 was 3.25 percent to 9.00 percent, maturing at various dates through March 2044. The range of interest rates for outstanding General Loans as of December 31, 2018 was 3.25 percent to 6.25 percent, maturing at various dates through January 2024.

Loan repayments are made through after-tax payroll deductions. Terminated employees generally have 60 days to elect to continue to make loan repayments or pay off the loan in full. Failure of the terminated employee to establish a loan repayment service or payoff the loan in full during this 60-day window generally results in a default of the loan, which is taxable income to the participant, with a possible 10 percent early withdrawal penalty. However, effective January 1, 2018, terminated employees who roll over their Plan account balance to an individual retirement account (“IRA”), Roth IRA, or other employer plan during this 60-day window may avoid such taxable income and 10 percent early withdrawal penalty if they pay off the outstanding loan balance to the rollover recipient IRA custodian or employer plan by the due date (including extensions) for filing their federal income tax return for the year in which the rollover occurred.

NOTE 5 — TAX STATUS

The Internal Revenue Service has determined and informed the Plan, by a letter dated August 21, 2014, that the Plan is qualified as a tax-exempt plan under the appropriate sections of the IRC. The determination letter covered Plan amendments adopted from September 17, 2010 through August 5, 2014, and the trust agreement with Fidelity adopted on July 19, 2013. The Plan has been amended since receiving the determination letter; however, the Plan Administrator believes that the Plan is currently designed and operated in compliance with the applicable requirements of the IRC. Therefore, the Plan is tax-exempt as of the financial statement date and no provision for income taxes has been recorded in the financial statements.

NOTE 6 — PARTY-IN-INTEREST TRANSACTIONS

Certain Plan investments include common collective trusts that are managed by affiliates of Fidelity. Fidelity is the trustee and third-party administrator as defined by the Plan; therefore, these transactions qualify as party-in-interest transactions.

Transactions in Microsoft Common Stock also qualify as party-in-interest transactions. As of December 31, 2018 and 2017, the Plan held 17,035,793 shares of Microsoft Common Stock valued at $1,730,325,484 and 17,841,741 shares of Microsoft Common Stock valued at $1,526,182,502, respectively. During the years ended December 31, 2018 and 2017, the Plan recorded Microsoft Common Stock dividend income of $29,844,171 and $29,683,123, respectively.

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NOTE 7 — RECONCILIATION OF FINANCIAL STATEMENTS TO FORM 5500

The following is a reconciliation of net assets available for benefits per the financial statements to net assets per the Form 5500, which is the annual return/report for the Plan:

Benefits payable are recorded on the Form 5500 for payments to participants who requested payment by December 31, but had not been paid as of that date.

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MICROSOFT CORPORATION

SAVINGS PLUS 401(k) PLAN

EMPLOYER ID 91-1144442, PLAN 001

SUPPLEMENTAL SCHEDULE OF ASSETS (HELD AT END OF YEAR)

AS OF DECEMBER 31, 2018

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