State Street Corporation is an American multinational financial services and bank holding company headquartered at One Congress Street in Boston. It is the second-oldest continuously operating U.S. bank, tracing its roots to Union Bank, chartered in 1792. As of the third quarter of 2025, State Street is one of the world's largest asset managers and custodians, with approximately US$5.4 trillion in assets under management and US$51.7 trillion under custody and administration.
State Street operates globally through three main divisions: Global Services (custody and fund administration), Global Advisors (asset management), and Global Markets (trading and research). It is considered a systemically important bank by the Financial Stability Board and ranks among the "Big Three" index fund managers alongside BlackRock and Vanguard.