A repo is a short-term borrowing arrangement where one party sells securities (usually Treasuries) and simultaneously agrees to repurchase them at a slightly higher price on a set future date — economically equivalent to a collateralized loan.
Why It Matters
The repo market is the plumbing of short-term funding for banks, dealers, and hedge funds — trillions of dollars turn over daily, and repo rates are a direct input to the Fed's monetary policy implementation (SOFR, the current benchmark that replaced LIBOR, is derived from repo transactions). A repo market seizure, as happened briefly in September 2019, can cascade into broader funding stress fast.
How It Works in Practice
- 1The cash borrower sells securities to the cash lender and agrees to repurchase them later at a higher price — the price difference is effectively the interest (the repo rate)
- 2The securities serve as collateral; if the borrower defaults, the lender keeps them
- 3Overnight repo is most common, but term repos run days to months
- 4A 'reverse repo' is the same transaction from the cash lender's side — buying securities with an agreement to sell them back
Common Pitfalls
Repo relies on the collateral being liquid and easily valued — during stress, even Treasury repo can seize up if dealers' balance sheets are constrained
Haircuts (the collateral value discount lenders apply) can widen suddenly in volatile markets, forcing borrowers to post more collateral or unwind positions
Heavy reliance on short-term repo funding for longer-term assets creates maturity mismatch risk — a core driver of the 2008 crisis for firms like Bear Stearns and Lehman