Deposit Insurance Fund (DIF)

The Deposit Insurance Fund (DIF) is the fund that the Federal Deposit Insurance Corporation uses to protect depositors at US banks and savings institutions. When an insured bank fails, the DIF pays insured depositors or covers the cost of transferring their accounts to another bank. The fund is financed mainly by assessments, a form of insurance premium, charged to insured banks, and by interest on its investments in US Treasury securities, not by annual appropriations from Congress.

The DIF is the financial engine behind US deposit insurance, which covers 250,000 dollars per depositor, per insured bank, for each ownership category, as of November 2026. Credit unions are covered separately by the National Credit Union Share Insurance Fund, run by the NCUA. How the coverage applies to money held through fintech and brokerage arrangements is described under pass-through deposit insurance, and balances above the limit under uninsured deposits.

Picture a group of neighbours who each pay a small amount every year into a shared repair fund, with those living in older houses paying a bit more. When a roof collapses, the fund pays for the repair so that the family is not left homeless.

The DIF works like that for banks. Every insured bank pays in, riskier banks pay more, and when one bank fails the fund makes sure its ordinary depositors get their money back, usually within days. Taxpayers are a last-resort backstop, not the first line of protection.

Federal deposit insurance began with the Banking Act of 1933, which created the FDIC after waves of bank failures and bank runs in the Great Depression. For decades banks and savings associations were insured through separate funds; after the savings and loan crisis, the Bank Insurance Fund and the Savings Association Insurance Fund existed side by side. The Federal Deposit Insurance Reform Act of 2005 merged them into the single Deposit Insurance Fund in 2006 and gave the FDIC more flexibility to set risk-based assessments. During the 2008 to 2010 crisis, bank failures pushed the fund's balance below zero, and the FDIC required banks to prepay three years of assessments in 2009 to restore its cash. The Dodd-Frank Act of 2010 made the 250,000-dollar coverage limit permanent and changed the assessment base from deposits to roughly a bank's total liabilities.

The health of the fund is measured by its reserve ratio:

The DIF balance is the fund's net worth, and estimated insured deposits are the deposits covered by insurance across all insured institutions. If the fund held 140 billion dollars and insured deposits totalled 10.5 trillion dollars, the reserve ratio would be 140 ÷ 10,500 × 100 = 1.33 per cent. The Dodd-Frank Act set a statutory minimum reserve ratio of 1.35 per cent, and the FDIC's board has set a long-term designated reserve ratio of 2 per cent. When the ratio falls below the minimum, the FDIC must adopt a restoration plan, as it did after a surge in deposits in 2020, and in 2022 it raised assessment rates for all banks to rebuild the fund.

• Payouts. Paying insured depositors directly when no buyer takes over the failed bank's deposits.
• Purchase and assumption. Covering the gap when another bank takes on the deposits and some assets of a failed bank, the most common resolution method.
• Bridge banks and loss-sharing. Funding temporary bridge banks and agreements under which the FDIC shares losses on assets sold to a buyer.
• Recoveries. Recovering money by selling the failed bank's assets, which offsets the fund's costs over time.

The fund is backed by the full faith and credit of the US government, and the FDIC can borrow from the Treasury if needed. US law generally requires the FDIC to choose the least costly method of resolving a failed bank, unless a systemic risk exception is approved. Abroad, comparable funds include the one behind the UK's Financial Services Compensation Scheme. A bank resolution fund is different, because it pays for restructuring failing banks rather than repaying depositors.

When Silicon Valley Bank and Signature Bank failed in March 2023, the Treasury, the Federal Reserve and the FDIC invoked the systemic risk exception so that all depositors, including those above the insured limit, were protected. The losses fell on the DIF. As the law requires, the FDIC recovered the cost of protecting uninsured depositors through a special assessment, which it designed to fall mainly on the largest banks, based on their uninsured deposits above 5 billion dollars. The episode renewed debate about whether coverage limits should be raised, particularly for business payment accounts, and about how much insurance costs smaller banks compared with large ones. Insured institutions advertise their membership under FDIC rules on the official sign and on misrepresentation of insurance, which also apply to fintech partners that market bank accounts.

• Federal Deposit Insurance Corporation