Repurchase Agreement (Repo)

A repurchase agreement — or repo — is a short-term collateralized borrowing transaction. Party A sells securities to Party B with an agreement to repurchase them at a specified future date (typically next day to a few weeks) at a higher price. The difference in prices is the implied interest rate. Repos are core to banking and money markets, providing short-term liquidity backed by collateral.

How a repo transaction works

Party A owns $100 million of Treasury bonds. It needs cash immediately and agrees to sell those bonds to Party B for $99.5 million with an agreement to repurchase them tomorrow for $99.6 million.

Party A has effectively borrowed $99.5 million for one day, with the collateral being Treasury bonds. The $100,000 difference (from $99.5M to $99.6M) is the interest paid, equivalent to a 0.1% daily rate or approximately 36% annualized (0.1% × 365 days).

This is the core repo mechanism: collateralized borrowing using securities as collateral. Party A gets cash and retains economic exposure to the bonds. Party B gets Treasury bonds as collateral and earns the repo rate.

Haircuts and overcollateralization

The repo rate reflects the quality of collateral. Treasury repos (backed by default-free U.S. Treasury bonds) trade at lower rates than corporate bond repos (backed by bonds with default risk).

Most repos require overcollateralization through “haircuts” — discounts applied to collateral values. If Treasury bonds are sold at par with a 2% haircut, they are valued at 98 cents on the dollar. This provides Party B cushion: if Party A defaults and Party B must sell the bonds, a 2% decline in value is covered by the haircut.

Haircuts vary by collateral type and market conditions. During stable periods, Treasury haircuts might be 1–2%. During crises, they widen to 5–10% or more as risk increases.

Overnight vs. term repos

Overnight repos mature the next business day and are rolled over daily. Most repo activity is overnight — banks borrow cash overnight to finance trading positions and securities holdings.

Term repos mature on a specified future date (1 week, 2 weeks, 1 month, 3 months). Term repos are used for more stable, longer-duration funding needs.

The spread between overnight and term rates reflects expectations about future overnight rates. If overnight rates are expected to rise, term rates are higher.

Reverse repos

A reverse repo is the opposite side of a repo transaction. If Party A is doing a repo (selling securities for cash with repurchase), Party B is doing a reverse repo (buying securities with an agreement to sell back).

The Federal Reserve conducts large-scale reverse repo operations to drain cash from the banking system when money is plentiful. Large corporations with excess cash conduct reverse repos to earn a return on that cash.

Role in financial system

Repos are the lifeblood of modern finance. Banks use repos to finance bond inventories, match-book trading positions, and manage short-term liquidity. Leverage in the financial system is often implemented through repo markets.

The 2008 financial crisis exposed repo vulnerability. When Lehman Brothers collapsed, the repo markets seized because counterparties feared default. The Fed intervened with emergency lending and explicit support for repo markets.

The 2019 “repo crisis” (when overnight rates spiked to 10%+) illustrated continued repo fragility. When large banks reduced repo lending, rates spiked, forcing the Fed to intervene again. This event highlighted systemic stress vulnerability.

Central bank operations

The Federal Reserve uses repos as a primary tool for managing interest rates and banking system liquidity. Repos inject cash when the Fed wants to lower overnight rates; reverse repos drain cash when the Fed wants to raise rates.

In 2008, the Fed created the Primary Dealer Credit Facility (PDCF) to provide emergency repo lending to broker-dealers facing funding stress.

Regulatory changes post-2008

Post-crisis, regulation tightened. Banks must now maintain higher capital and liquidity buffers to support repo obligations. Repos cleared through central clearing houses are more transparent and standardized. Haircuts increased for riskier collateral.

Still, repos remain an essential and largely unregulated corner of the financial system, creating systemic risk concentration.

See also