UNITED STATES

SECURITIES AND EXCHANGE COMMISSION

WASHINGTON, D.C. 20549

FORM 8-K

CURRENT REPORT

PURSUANT TO SECTION 13 OR 15(d)

OF THE SECURITIES EXCHANGE ACT OF 1934

Date of report (Date of earliest event reported): September 16, 2015

METLIFE, INC.

(Exact Name of Registrant as Specified in Its Charter)

212-578-9500

(Registrant’s Telephone Number, Including Area Code)

N/A

(Former Name or Former Address, if Changed Since Last Report)

Check the appropriate box below if the Form 8-K filing is intended to simultaneously satisfy the filing obligation of the registrant under any of the following provisions (see General Instruction A.2. below):

On September 16, 2015, MetLife, Inc. (the “Company” or “MetLife”) issued a news release regarding a third quarter non-cash charge, as further described below. A copy of the news release is attached hereto as Exhibit 99.1 and is incorporated herein by reference.

During the third quarter of 2015, MetLife expects to record a non-cash charge to operating earnings and net income of $792 million, after tax, ($0.70 per share) related to the tax treatment of a wholly-owned U.K. investment subsidiary of Metropolitan Life Insurance Company (“MLIC”), a wholly-owned subsidiary of the Company. (“Operating earnings,” “operating earnings per share” and other non-GAAP measures used in this Form 8-K are defined in the footnote below.)* This charge, which is being recorded under accounting guidance for the recognition of tax uncertainties, is the result of the Company’s consideration of recent decisions of the U.S. Court of Appeals for the Second Circuit (“Second Circuit”) upholding the disallowance of foreign tax credits claimed by other corporate entities not affiliated with the Company.

The Company’s action relates to tax years from 2000 to 2009 during which MLIC held non-U.S. investments in support of its life insurance business through a U.K. investment subsidiary that was structured as a joint venture at the time. During that time, the Company continued to pay the same amount of aggregate taxes on the non-U.S. investments as if MLIC had directly owned the investments. As a U.K. entity, the joint venture’s income from the investments was taxable in the U.K., and most of the taxes were paid to the U.K. taxing authority. As required by U.S. law, MetLife also paid additional taxes to the Internal Revenue Service (“IRS”) to the extent the U.S. tax rate was higher than the U.K. tax rate. What is primarily in dispute with the IRS is whether it was appropriate for the Company to reduce its U.S. taxes due to credits for U.K. taxes or whether the Company must also pay U.S. taxes at the full U.S. rate. As previously disclosed in the Company’s Form 10-Q for the quarter ended June 30, 2015, the IRS disallowed the use of foreign tax credits for the 2000 to 2002 tax years and is also likely to challenge their use during the 2003 to 2009 tax years.

As previously disclosed in the notes to its consolidated financial statements included in the Company’s Form 10-K for the year ended December 31, 2014, the Company determines whether it is more likely than not that a tax position will be sustained upon examination by the appropriate taxing authorities before any part of the benefit can be recorded in the financial statements. A tax position is measured at the largest amount of benefit that is greater than 50% likely of being realized upon settlement. The Company may be required to change its provision for income taxes when receipt of new information indicates the need for adjustment in recorded balances. Prior to the recent decisions in the Second Circuit, other Federal courts have reached differing outcomes when considering foreign tax credit disputes. However, the recent decisions by the Second Circuit, where the Company is located, have led management to reserve fully for this matter under those accounting guidelines. After the Company records this charge in the third quarter, the Company does not expect any additional charges related to this matter.

On a statutory basis, the third quarter charge for MLIC will be $911 million, after tax. This charge has no impact on the previously disclosed $1.2 billion of dividends permitted to be paid in 2015 by MLIC without regulatory approval. We expect the impact to dividends permitted to be paid in 2016 without regulatory approval to be a reduction of approximately $90 million.

There has been no change in the Company’s position on the disallowance of its foreign tax credits by the IRS. MetLife continues to contest the disallowance of these foreign tax credits by the IRS as management believes the facts strongly support the Company’s position.

* References in this Form 8-K (except in this footnote) to net income (loss), net income (loss) per share, operating earnings and operating earnings per share should be read as net income (loss) available to MetLife, Inc.’s common shareholders, net income (loss) available to MetLife, Inc.’s common shareholders per diluted common share, operating earnings available to common shareholders and operating earnings available to common shareholders per diluted common share, respectively.

Operating earnings is the measure of segment profit or loss that MetLife uses to evaluate segment performance and allocate resources. Consistent with accounting principles generally accepted in the United States of America (GAAP) accounting guidance for segment reporting, operating earnings is MetLife’s measure of segment performance. Operating earnings is also a measure by which MetLife senior management’s and many other employees’ performance is evaluated for the purposes of determining their compensation under applicable compensation plans.

Operating earnings is defined as operating revenues less operating expenses, both net of income tax. Operating earnings available to common shareholders is defined as operating earnings less preferred stock dividends.

Operating revenues and operating expenses exclude results of discontinued operations and other businesses that have been or will be sold or exited by MetLife and are referred to as divested businesses. Operating revenues also excludes net investment gains (losses) (NIGL) and net derivative gains (losses) (NDGL). Operating expenses also excludes goodwill impairments.

The following additional adjustments are made to GAAP revenues, in the line items indicated, in calculating operating revenues:

The following additional adjustments are made to GAAP expenses, in the line items indicated, in calculating operating expenses:

Operating earnings also excludes the recognition of certain contingent assets and liabilities that could not be recognized at acquisition or adjusted for during the measurement period under GAAP business combination accounting guidance. In addition to the tax impact of the adjustments mentioned above, provision for income tax (expense) benefit also includes the impact related to the timing of certain tax credits, as well as certain tax reforms.

MetLife believes the presentation of operating earnings and operating earnings available to common shareholders as MetLife measures it for management purposes enhances the understanding of the company’s performance by highlighting the results of operations and the underlying profitability drivers of the business. Operating revenues, operating expenses, operating earnings, operating earnings available to common shareholders, operating earnings available to common shareholders per diluted common share, investment portfolio gains (losses) and derivative gains (losses) should not be viewed as substitutes for the following financial measures calculated in accordance with GAAP: GAAP revenues, GAAP expenses, income (loss) from continuing operations, net of income tax, net income (loss) available to MetLife, Inc.’s common shareholders, net income (loss) available to MetLife, Inc.’s common shareholders per diluted common share, net investment gains (losses) and net derivative gains (losses), respectively.

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Note Regarding Forward-Looking Statements

This Report on Form 8-K may contain or incorporate by reference information that includes or is based upon forward-looking statements within the meaning of the Private Securities Litigation Reform Act of 1995. Forward-looking statements give expectations or forecasts of future events. These statements can be identified by the fact that they do not relate strictly to historical or current facts. They use words such as “anticipate,” “estimate,” “expect,” “project,” “intend,” “plan,” “believe” and other words and terms of similar meaning, or are tied to future periods, in connection with a discussion of future operating or financial performance. In particular, these include statements relating to future actions, prospective services or products, future performance or results of current and anticipated services or products, sales efforts, expenses, the outcome of contingencies such as legal proceedings, trends in operations and financial results.

Any or all forward-looking statements may turn out to be wrong. They can be affected by inaccurate assumptions or by known or unknown risks and uncertainties. Many such factors will be important in determining the actual future results of MetLife, Inc., its subsidiaries and affiliates. These statements are based on current expectations and the current economic environment. They involve a number of risks and uncertainties that are difficult to predict. These statements are not guarantees of future performance. Actual results could differ materially from those expressed or implied in the forward-looking statements. Risks, uncertainties, and other factors that might cause such differences include the risks, uncertainties and other factors identified in MetLife, Inc.’s filings with the U.S. Securities and Exchange Commission. These factors include: (1) difficult conditions in the global capital markets; (2) increased volatility and disruption of the capital and credit markets, which may affect our ability to meet liquidity needs and access capital, including through our credit facilities, generate fee income and market-related revenue and finance statutory reserve requirements and may require us to pledge collateral or make payments related to declines in value of specified assets, including assets supporting risks ceded to certain of our captive reinsurers or hedging arrangements associated with those risks; (3) exposure to financial and capital market risks, including as a result of the disruption in Europe and possible withdrawal of one or more countries from the Euro zone; (4) impact of comprehensive financial services regulation reform on us, as a non-bank systemically important financial institution, or otherwise; (5) numerous rulemaking initiatives required or permitted by the Dodd-Frank Wall Street Reform and Consumer Protection Act which may impact how we conduct our business, including those compelling the liquidation of certain financial institutions; (6) regulatory, legislative or tax changes relating to our insurance, international, or other operations that may affect the cost of, or demand for, our products or services, or increase the cost or administrative burdens of providing benefits to employees; (7) adverse results or other consequences from litigation, arbitration or regulatory investigations; (8) potential liquidity and other risks resulting from our participation in a securities lending program and other transactions; (9) investment losses and defaults, and changes to investment valuations; (10) changes in assumptions related to investment valuations, deferred policy acquisition costs, deferred sales inducements, value of business acquired or goodwill; (11) impairments of goodwill and realized losses or market value impairments to illiquid assets; (12) defaults on our mortgage loans; (13) the defaults or deteriorating credit of other financial institutions that could adversely affect us; (14) economic, political, legal, currency and other risks relating to our international operations, including with respect to fluctuations of exchange rates; (15) downgrades in our claims paying ability, financial strength or credit ratings; (16) a deterioration in the experience of the “closed block” established in connection with the reorganization of Metropolitan Life Insurance Company; (17) availability and effectiveness of reinsurance or indemnification arrangements, as well as any default or failure of counterparties to perform; (18) differences between actual claims experience and underwriting and reserving assumptions; (19) ineffectiveness of risk management policies and procedures; (20) catastrophe losses; (21) increasing cost and limited market capacity for statutory life insurance reserve financings; (22) heightened competition, including with respect to pricing, entry of new competitors, consolidation of distributors, the development of new products by

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new and existing competitors, and for personnel; (23) exposure to losses related to variable annuity guarantee benefits, including from significant and sustained downturns or extreme volatility in equity markets, reduced interest rates, unanticipated policyholder behavior, mortality or longevity, and the adjustment for nonperformance risk; (24) our ability to address difficulties, unforeseen liabilities, asset impairments, or rating agency actions arising from business acquisitions and integrating and managing the growth of such acquired businesses, or arising from dispositions of businesses or legal entity reorganizations; (25) regulatory and other restrictions affecting MetLife, Inc.’s ability to pay dividends and repurchase common stock; (26) MetLife, Inc.’s primary reliance, as a holding company, on dividends from its subsidiaries to meet debt payment obligations and the applicable regulatory restrictions on the ability of the subsidiaries to pay such dividends; (27) the possibility that MetLife, Inc.’s Board of Directors may influence the outcome of stockholder votes through the voting provisions of the MetLife Policyholder Trust; (28) changes in accounting standards, practices and/or policies; (29) increased expenses relating to pension and postretirement benefit plans, as well as health care and other employee benefits; (30) inability to protect our intellectual property rights or claims of infringement of the intellectual property rights of others; (31) inability to attract and retain sales representatives; (32) provisions of laws and our incorporation documents may delay, deter or prevent takeovers and corporate combinations involving MetLife; (33) the effects of business disruption or economic contraction due to disasters such as terrorist attacks, cyberattacks, other hostilities, or natural catastrophes, including any related impact on the value of our investment portfolio, our disaster recovery systems, cyber- or other information security systems and management continuity planning; (34) the effectiveness of our programs and practices in avoiding giving our associates incentives to take excessive risks; and (35) other risks and uncertainties described from time to time in MetLife, Inc.’s filings with the U.S. Securities and Exchange Commission.

MetLife, Inc. does not undertake any obligation to publicly correct or update any forward-looking statement if MetLife, Inc. later becomes aware that such statement is not likely to be achieved. Please consult any further disclosures MetLife, Inc. makes on related subjects in reports to the U.S. Securities and Exchange Commission.

(a) Not applicable.

(b) Not applicable.

(c) Not applicable.

(d) Exhibits

99.1     News release of MetLife, Inc., dated September 16, 2015, announcing non-cash charge.

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SIGNATURES

Pursuant to the requirements of the Securities Exchange Act of 1934, the registrant has duly caused this report to be signed on its behalf by the undersigned hereunto duly authorized.

Date: September 16, 2015

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EXHIBIT INDEX

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