Repo Market

A repurchase agreement ("repo") is a short-term collateralized loan structured as a sale and forward repurchase of securities, usually government bonds. The cash borrower sells securities to a lender today and agrees to buy them back—typically the next day (overnight repo) or within weeks (term repo)—at a marginally higher price. The price difference is effectively the interest, known as the repo rate. From the lender's perspective the transaction is a reverse repo.

The repo market is one of the largest and most important funding markets in the world. It allows banks, hedge funds, money market funds, and broker-dealers to finance large securities holdings cheaply, and it lets cash-rich institutions earn a return on idle balances while holding high-quality collateral. In the United States, repo activity is centered on U.S. Treasuries and agency mortgage-backed securities; in Europe, on sovereign bonds cleared through venues such as Eurex Repo and BrokerTec.

Central banks use repo operations as a core monetary policy tool. The Federal Reserve conducts repo and reverse repo operations through its New York trading desk to keep the federal funds rate within its target range; the European Central Bank uses main refinancing operations structured as repos to supply liquidity to euro-area banks.

Repo markets can transmit stress quickly. In September 2019, overnight repo rates in the U.S. spiked from around 2% to roughly 10%, prompting the Fed to inject liquidity through standing repo operations. The 2007–2008 financial crisis featured a "run on repo," where lenders refused to roll over funding to firms like Bear Stearns and Lehman Brothers as collateral values became suspect—a dynamic analyzed by economist Gary Gorton.

Key risks include counterparty default, collateral revaluation (managed through haircuts and daily margining), and fire-sale dynamics if many borrowers must liquidate collateral simultaneously. Post-crisis reforms, including central clearing through entities like the Fixed Income Clearing Corporation (FICC), aim to reduce systemic fragility.