Wellington Management Company is an American private, independent investment management firm with client assets under management totaling over US$1 trillion based in Boston, Massachusetts, United States.

The firm serves as an investment advisor to over 2,200 institutions in over 60 countries, as of 30 June 2020. Its clients include central banks and sovereign institutions, pension funds, endowments and foundations, family offices, fund sponsors, insurance companies, financial intermediaries, and wealth managers.

In 1928, Philadelphia-based accountant Walter L. Morgan established the first balanced mutual fund in the United States, the Wellington Fund. Wellington Management Company was incorporated in 1933.

In 1951, the firm hired John C. Bogle, who succeeded Morgan as chairman in 1970. In 1967, Wellington merged with Boston-based investment management firm Thorndike, Doran, Paine & Lewis. Bogle left in 1974 and established The Vanguard Group, retaining Wellington to manage some of Vanguard's funds.

In 1979, Wellington's 29 original partners bought back the firm after a period as a public company.

In 1994, Wellington offered its first Luxembourg-domiciled UCITS fund.

Also in 1994, Wellington offered its first hedge fund. Today, the firm manages alternatives assets for clients totaling over US$40 billion and offers over 40 funds.

In 2014, the firm offered its first dedicated private equity strategy.