MetLife, Inc. is the holding corporation for the Metropolitan Life Insurance Company (MLIC), better known as MetLife, and its affiliates. MetLife is among the largest global providers of insurance, annuities, and employee benefit programs, with 90 million customers in over 60 countries. The firm was founded on March 24, 1868.

On January 6, 1915, MetLife completed the mutualization process, changing from a stock life insurance company owned by individuals to a mutual company operating without external shareholders and for the benefit of policyholders. The company went public in 2000. Through its subsidiaries and affiliates, MetLife holds leading market positions in the United States, Japan, Latin America, Asia’s Pacific region, Europe, and the Middle East. MetLife serves 90 of the largest Fortune 500 companies. The company’s principal offices are located at 200 Park Avenue, New York City in Midtown Manhattan, New York City, though it retains some executive offices and its boardroom in the MetLife Building, located at 200 Park Avenue, New York City, which it sold in 2005.

In January 2016, the company announced that it would spin off U.S. Retail business, including individual life insurance and annuities for the retail market, in a separate company called Brighthouse Financial. They will maintain the MetLife name on MetLife Stadium. On March 6, 2017, the separated U.S. Retail business launched Brighthouse Financial – an independent company focused on life insurance and annuities.

As of 2010, the company was "organized into five segments: Insurance Products, Retirement Products," the US Business (including Auto & Home and Corporate Benefit Funding), and International. The Insurance Products division was the largest unit, accounting for 53% of 2009 revenue. By 2015, a division referred to as "Americas" had emerged.

As of 2011, MetLife's chief executive officer was Steve Kandarian. Kandarian also served as the company's chairman of the board and president as of 2015.

Hired in 2013, John Hele served as chief financial officer for the company as of 2015.

In 2015, MetLife hired Hugh Dineen to fill the new role of chief marketing officer within the US Business Unit.

As in many large, public corporations, MetLife has a compensation committee which establishes compensation levels for the company's senior executives; MetLife compensation emphasizes "variable performance-based compensation over fixed or guaranteed pay".

MetLife subsidiaries and affiliates have included MetLife Investors, MetLife Bank, MetLife Securities, Metropolitan Property and Casualty Insurance Company and its subsidiaries, General American, Hyatt Legal, MetLife Resources, New England Financial, Walnut Street Securities, Inc., Safeguard Health Enterprises, Inc., and Tower Square Securities, Inc., Cigna.

The subsidiary MetLife Insurance Company USA, as of 2015 headquartered in Charlotte, North Carolina, was formerly known as MetLife Insurance Company of Connecticut, and prior to this as Travelers Insurance Company.

MetLife Bank was sold to GE Capital in 2013, and MetLife exited the banking business.

The predecessor company to MetLife began in 1863 when a group of New York City businessmen raised $100,000 to found the National Union Life and Limb Insurance Company. The company insured Civil War sailors and soldiers against disabilities due to wartime wounds, accidents, and sickness. On March 24, 1868, it became known as Metropolitan Life Insurance Company and shifted its focus to the life insurance business.

A severe business depression that began with the Panic of 1873 forced the company to contract, until it reached its lowest point in the late 1870s. After observing the insurance industry in Great Britain in 1879, MetLife President Joseph F. Knapp brought “industrial” or “workingmen’s” insurance programs to the United States – insurance issued in small amounts on which premiums were collected weekly or monthly at the policyholder’s home. By 1880, sales had exceeded a quarter million of such policies, resulting in nearly $1 million in revenue from premiums. In 1909, MetLife had become the nation’s largest life insurer in the United States, as measured by life insurance in force (the total value of life insurance policies issued).

In 1907, the Metropolitan Life Insurance Company tower was commissioned to serve as MetLife’s 23rd Street headquarters in Lower Manhattan. Completed two years later, the building was the world's tallest until 1913 and remained the company's headquarters until 2005. For many years, an illustration of the building (with light emanating from the tip of its spire and the slogan, "The Light That Never Fails") featured prominently in MetLife’s advertising. By 1930, MetLife insured every fifth man, woman, and child in the United States and Canada. During the 1930s, it also began to diversify its portfolio by reducing the percentage of individual mortgages in favor of public utility bonds, investments in government securities, and loans for commercial real estate. The company financed the construction of the Empire State Building in 1929 as well as provided capital to build Rockefeller Center in 1931. During World War II, MetLife placed more than 51 percent of its total assets in war bonds, and was the largest single private contributor to the Allied cause.

During the postwar era, the company expanded its suburban presence, decentralized operations, and refocused its career agency system to serve all market segments. It also began to market group insurance products to employers and institutions. By 1979, operations were segmented into four primary businesses: group insurance, personal insurance, pensions, and investments. In 1981, MetLife purchased what became known as the MetLife building for $400 million from a group that included Pan American World Airways.

In 2000, MetLife converted from a mutual insurance company operated for the benefit of its policyholders to a for-profit public company. The de-mutualization process allowed MetLife to enter unrelated insurance businesses and increase executive compensation.

Policyholders received some stock in the new company in this process. MetLife was accused of breaching federal securities laws by misrepresenting and omitting information in materials given to policyholders during this process, resulting in years of litigation ending with a $50 million settlement in 2009.

From 2004 to 2011, MetLife continued to hold its position as the largest life insurer in the United States. The company had $2.5 trillion in policies written, $350 billion in assets under management, over 12 million customers in the United States, 8 million customers outside the United States, and a net income in 2003 of $2.2 billion. That year, Barron's reported that 13 million American households owned at least one product from MetLife.

MetLife named Robert H. Benmosche as chairman and CEO in July 1999. Benmosche occupied the position until 2006, when he was replaced by C. Robert Henrikson.

The company's sales grew 11.5% between 2008 and 2009, despite the national recession. In 2011, CEO Robert Henrikson was replaced by Steven A. Kandarian, who had overseen the company's "US$450,000,000,000 investment portfolio" as chief investment officer. Henrikson remained the company's chairman to the end of 2011, at which point he reached the company's mandatory retirement age.

In 2015, MetLife was ranked as number one on Fortune magazine's list of World's Most Admired Companies in the Insurance: Life and Health category.

In the summer of 2017, MetLife plans to add a third office building of 255,000 square feet at its Cary, North Carolina Global Technology Campus, giving the company a total of 655,000 square feet at a location which has over 1,000 employees in such areas as engineering, software and technology. This plan was the result of North Carolina awarding the company $94 million in incentives in 2013 for creating over 2,600 jobs, half in Cary and half in Charlotte.

In 2012, MetLife failed the Federal Reserve’s (the Fed's) Comprehensive Capital Analysis and Review stress test, intended to predict the potential failure of the company in a recession. The Fed stated that the minimum total risk-based capital ratio should be 8% and it estimated MetLife's ratio at 6%. The company had requested approval for a US$2,000,000,000 share repurchase to prop up the stock price, along with an increased dividend. Because MetLife owned MetLife Bank, it was subject to stricter financial regulation. To escape that level of regulation, MetLife announced the sale of its banking unit to GE Capital. On November 2, 2012, MetLife said it was selling its US$70,000,000,000 mortgage servicing business to JPMorgan Chase for an undisclosed amount. Both sales were part of its strategy to focus on the insurance side of its business.

The attempt to escape "too big to fail" regulation was not successful. In September 2014, the United States government observed the 2010 Dodd-Frank financial reform law by proposing the application of an official label to MetLife as "systemically important" to the American economy. If implemented, MetLife would be subject to different sets of rules and regulations, with increased oversight from the Federal Reserve. The company appealed this proposal in November 2014. In December 2014, federal regulators decided that MetLife required the special regulations reserved for financial companies and organizations deemed "systemically important," or "too big to fail". MetLife announced in January 2015 that it would file a lawsuit against the District of Columbia to overturn the federal regulators' decision, thus becoming the first nonbank to challenge such a decision. Three other nonbank companies have been designated as "systemically important": AIG, General Electric and Prudential. MetLife continued to litigate this issue as of mid-2015, with the US Department of Justice asking that their challenge be dismissed.

On August 7, 2012, it was announced that MetLife will pay $3.2 million in fines after the Federal Reserve charged it used unsafe and unsound practices in handling its mortgage servicing and foreclosure operations.

In 2014, MetLife paid $23 million to settle multiple lawsuits over junk fax operations used to generate leads for life insurance sales.

In 2015, MetLife Home Loans LLC paid $123.5 million to the United States Department of Justice to resolve allegations it knowingly made mortgages insured by the United States government that didn’t meet federal underwriting requirements.

As of 2010, MetLife had a "diverse product mix" which included insurance (home, car and life), variable life annuities and structured settlements, commercial mortgages and securities backed by commercial mortgages, and sovereign debt.

MetLife’s individual life insurance products and services comprise term life insurance and several types of permanent life insurance, including whole life, universal life, and final expense whole life insurance. These services vary in regards to the duration and amount of coverage available and whether a medical exam is required for coverage. The company also offers group life insurance, provided through employers, which consists of term life, permanent life, and accidental death and dismemberment coverage. MetLife is the largest life insurer in the United States, based on life insurance in-force.

MetLife offers group dental benefit plans for individuals, employees, retirees and their families and provides dental plan administration for over 20 million people. Plans include MetLife’s Preferred Dentist Program (PPO) and the SafeGuard DHMO (available for both individuals and employees in CA, FL, TX, NJ and NY.). As of May 2010, MetLife’s dental PPO network included over 135,000 participating dentist locations nationwide while the dental HMO network included more than 13,000 participating dentist locations in California, Florida and Texas. MetLife also administers dental continuing education program for dentists and allied health care professionals, which are recognized by the American Dental Association (ADA) and the Academy of General Dentistry (AGD).

MetLife provides disability products for individuals as well as employee and association groups who receive them through their employer. For individuals, the company’s individual disability income insurance can replace a portion of lost income if an individual is unable to work due to sickness or injury. MetLife offers several individual disability income policies, including MetLife Income Guard, OMNI Advantage, OMNI Essential, Business Overhead Expense, and Buy-Sell. The policy options provided by the company vary in terms of eligibility and the provided coverage. For groups, MetLife offers short term disability insurance and long term disability insurance. Short term disability insurance is structured to replace a portion of an individual’s income during the initial weeks of a disabling illness or accident. Long term disability Insurance serves to replace a portion of an individual’s income during an extended period of a disabling illness or accident. The company also maintains an absence management product which allows employers to track and manage both planned and unplanned employee absences. The product, which MetLife calls MetLife Total Absence Management, is structured for businesses with 1,000 or more employees.

MetLife is among the largest providers of annuities in the world, recording $22.4 billion in sales during 2009. MetLife offers annuities which consist of fixed annuities, variable annuities, deferred annuities and immediate annuities. In 1921, MetLife was the first company to issue a group annuity contract. More recently in 2004, it was the first insurer to introduce a longevity insurance product. As of December 31, 2009, MetLife globally managed group annuity assets of $60 billion with $34 billion of transferred pension liabilities and provided benefit payments to over 600,000 annuitants per month.

MetLife Auto & Home is the brand name for MetLife’s nine affiliate personal lines insurance companies. Collectively these companies offer personal lines property and casualty insurance policies in all 50 states and the District of Columbia. The flagship company in the MetLife Auto & Home group, Metropolitan Property and Casualty Insurance Company, was founded in 1972. MetLife Auto & Home companies presently have over 2.7 million active policies and service 58 of the Fortune 100 companies.

MetLife's home insurance solutions include homeowners insurance, condo insurance, renters insurance, insurance for landlords, and mobile home insurance. The available policies for MetLife's home insurance provide coverage for possessions, property damage from natural disaster or theft, and various legal expenses incurred resulting from injuries sustained on an individual's property. The companies also sell RV, ATV, boat, mobile home, collectible vehicle, and motorcycle policies and offers flood insurance policies as a participant in the National Flood Insurance Program (NFIP), which is managed by the federal government. MetLife's various types of coverage for auto insurance include liability protection, collision and comprehensive coverage, personal injury protection, rental car coverage, and uninsured and underinsured motorists coverage. Through an arrangement with Hyatt Legal Plans, a subsidiary of MetLife, MetLife Auto & Home underwrites group legal plans in many states.

It was the first national insurer in the United States to offer identity-theft resolution services at no extra premium and as of 2012 continues to do so today in most United States states. In 2010, MetLife Auto & Home began offering their GrandProtect plan in most states. This GrandProtect policy simplifies complex insurance needs by combining a client's home, valuable items, autos, RVs, and boats into one comprehensive policy package. The ultimate benefits to the consumer are having one bill, only one deductible, comprehensive coverage, and typically lower rates than trying to get each policy individually.

MetLife’s products also include critical illness insurance. Financial services include fee-based financial planning, retirement planning, wealth management, 529 Plans, banking, and commercial and residential mortgages. The company also provides retirement plan and other financial services to healthcare, education, and not-for-profit organizations. The MetLife Center for Special Needs Planning is a group of planners which serve families and individuals with special needs. In 2014, MetLife launched MetLife Defender, a digital identity theft protection product.

Outside of the United States, MetLife operates in Latin America, Europe, Asia’s Pacific region, and the Middle East, with leading market positions in Mexico, Japan, South Korea and Chile.

On March 8, 2010, MetLife announced its intent to purchase the international leader life-insurance business, American Life Insurance Company (Alico), from American International Group (AIG). MetLife, which completed the deal on November 1, 2010, paid approximately $7.2 billion in cash and $9.0 billion in MetLife equity and other securities. The securities portion of the deal consisted of 78.2 million shares of MetLife common stock, 6.9 million shares of contingent convertible preferred stock and 40 million equity units. The values of the common and preferred stock were based on the closing price of MetLife’s common stock on October 29. Upon completion of the purchase, MetLife became a leading competitor in Japan, the world’s second-largest life insurance market, and moved into a top 5 market position in many high growth emerging markets in Central and Eastern Europe, such as Romania, the Middle East and Latin America. The deal added 20 million customers to MetLife’s 70 million and according to Barron's more than doubled the percentage of operating profits that MetLife gets abroad to 40%.

In India MetLife has an affiliate company India Insurance Company Limited (MetLife) which has operated in India since 2001. This company has its headquarters in Bangalore and Gurgaon and was jointly owned by MetLife and a few local Indian financial companies. In 2012 an agreement was made with local Indian bank, the Punjab National Bank to establish a strategic alliance and for it to take a 30% share in MetLife India. The state owned bank would in return sell MetLife insurance products in its branches

As of 2015, Julio Garcia-Villalon leads the Middle East & Africa regional business, which is headquartered in the Dubai International Financial Centre and has operated in the region since the 1950s.

MetLife Foundation is MetLife's independent charitable and grant-awarding foundation. It was founded in 1976 and had provided over $650 million in grants by January 2015. The foundation has partnered with and donated to a variety of organizations, including Habitat for Humanity since 2010 and the Martin Luther King, Jr. National Memorial Project Foundation since 2008. In 2013, the MetLife Foundation announced a new focus on financial inclusion, including educational programs on basic financial planning for disadvantaged children and financial services aimed at low-income communities.

MetLife's use of comic strip characters, according to chief marketing officer Esther Lee, was intended "to make our company more friendly and approachable during a time when insurance companies were seen as cold and distant."

MetLife licensed Snoopy and other Peanuts characters for promotional purposes from the Iconix Brand Group, which owns the promotional rights to the works of Charles M. Schulz. In 2010, Iconix formed a joint venture with Schulz’s heirs, buying out E. W. Scripps Co. and United Features Syndicate for $175 million. MetLife is reported to pay $12 million per year to Iconix for licensing rights. Prior to the Iconix deal, MetLife had licensed the characters from other rights-holders.

The Peanuts-based campaign was developed by the advertising agency Young & Rubicam. MetLife also has used Foote Cone & Belding to develop Peanuts-related promotions.

MetLife announced the end of its 31-year relationship with Peanuts on October 20, 2016. This decision resulted from the company's sale of its life insurance business to concentrate on corporate clients. MetLife's new blue and green logo was criticized for being a knock-off of comparison website Diffen.

The MetLife blimp program began in 1987 with the “Snoopy 1” airship and, in 1994, expanded to include the “Snoopy 2” airship. The program provides aerial coverage to over 80 major sporting events every year and is currently the official aerial coverage provider of the PGA Tour. “Snoopy 1” and “Snoopy 2” also provide overhead television coverage for the NFL, CBS College Football, the LPGA, the NBA Finals, Copa Chile, the Preakness Stakes, and the Kentucky Derby. On August 23, 2011, MetLife agreed to a 25-year sponsorship deal to rename New Meadowlands Stadium in East Rutherford, New Jersey, home of the NFL's New York Giants and New York Jets to MetLife Stadium.

In 1959, The Metropolitan Life Insurance Company (as it was known at the time) released tables of the best weight for each height for longevity, based on their collected insurance data. These tables showed the “desirable weights”. In 1983, they released tables showing the “ideal” weights for greatest longevity; this information was based on data collected in the Build Study of 1979 collected by the Society of Actuaries. This data followed patients for 18 years (from 1954-1972) and was collected from 25 life insurance companies in Canada and the United States, representing 4.2 million people. These “ideal” weights were higher than the prior “desirable” weights, this was attributed to an increase in muscle mass due to improved fitness levels among the population. This study is still the largest available pool of data for this purpose. It was noticed that the average weights in the population are higher than the ideal weights for survival. The ‘’’Metropolitan Tables’’’ included ‘’small’’, ‘’medium’’ and ‘’large’’ frames, based on elbow-girth measured using calipers, as the elbows do not develop adipose tissue. They presented weight ranges for height, sex and body frame (again associated with the lowest mortality) The mid-point of the ideal weight for the medium frames for each height was selected as the “ideal” weight used for calculations of “excess weight” (initial weight-ideal weight). This led to a formula to calculate the ideal weight used by bariatric surgeons, but it had lost considerable accuracy by 2007, again due to improvements in medical care and in public health.