The Federal Deposit Insurance Corporation (FDIC) is a United States government corporation supplying deposit insurance to depositors in American commercial banks and savings banks.^: 15 The FDIC was created by the Banking Act of 1933, enacted during the Great Depression to restore trust in the American banking system. More than one-third of banks failed in the years before the FDIC's creation, and bank runs were common.^: 15 The insurance limit was initially US$2,500 per ownership category, and this was increased several times over the years. Since the enactment of the Dodd–Frank Wall Street Reform and Consumer Protection Act in 2010, the FDIC insures deposits in member banks up to $250,000 per ownership category. FDIC insurance is backed by the full faith and credit of the government of the United States, and according to the FDIC, "since its start in 1933 no depositor has ever lost a penny of FDIC-insured funds".

The FDIC is not supported by public funds; member banks' insurance dues are its primary source of funding. The FDIC charges premiums based upon the risk that the insured bank poses. When dues and the proceeds of bank liquidations are insufficient, it can borrow from the federal government, or issue debt through the Federal Financing Bank on terms that the bank decides.

As of September 2019, the FDIC provided deposit insurance at 5,256 institutions. As of Q3 2022, the Deposit Insurance Fund stood at $125.5bn with annual Assessment Revenue (insurance premiums) of $8.1bn (12 months to Q3 2022).

The FDIC also examines and supervises certain financial institutions for safety and soundness, performs certain consumer-protection functions, and manages receiverships of failed banks. Quarterly reports are published indicating details of the banks’ financial performance, including leverage ratio (but not CET1 Capital Requirements & Liquidity Coverage Ratio as specified in Basel III).