# Repurchase Agreement (Repo): How the Short-Term Funding Market Works Published: 2026-02-07 Author: Warren Team URL: https://www.heywarren.com/blog/repurchase-agreement --- The repo market is the plumbing of the global financial system — moving trillions of dollars in short-term funding each day. When the repo market malfunctions (as it did in September 2019 and March 2020), central banks intervene immediately because disruptions there cascade through every other market. Here's how repo actually works. ## What Is a Repurchase Agreement? A **repurchase agreement (repo)** is a short-[term borrowing](/blog/term-borrowing) arrangement where one party (the seller) sells securities to another (the buyer) with an agreement to repurchase them at a higher price on a specified future date. ![In a repo, the borrower sells securities for cash today and repurchases them at a higher price tomorrow — effectively a one-day collateralized loan.](data:image/svg+xml,%3Csvg%20xmlns%3D%22http%3A%2F%2Fwww.w3.org%2F2000%2Fsvg%22%20viewBox%3D%220%200%201090%20125%22%20width%3D%221090%22%20height%3D%22125%22%20role%3D%22img%22%3E%3Ctitle%3EFlow%20diagram%3C%2Ftitle%3E%3Crect%20width%3D%22100%25%22%20height%3D%22100%25%22%20fill%3D%22%23f8fafc%22%2F%3E%3Crect%20x%3D%2230%22%20y%3D%2225%22%20width%3D%22170%22%20height%3D%2275%22%20rx%3D%2210%22%20fill%3D%22white%22%20stroke%3D%22%232563eb%22%20stroke-width%3D%222%22%2F%3E%3Ctext%20x%3D%22115%22%20y%3D%2258.5%22%20text-anchor%3D%22middle%22%20font-family%3D%22system-ui%2C-apple-system%2Csans-serif%22%20font-size%3D%2214%22%20font-weight%3D%22600%22%20fill%3D%22%230f172a%22%3EBank%20A%3C%2Ftext%3E%3Ctext%20x%3D%22115%22%20y%3D%2278.5%22%20text-anchor%3D%22middle%22%20font-family%3D%22system-ui%2C-apple-system%2Csans-serif%22%20font-size%3D%2211%22%20fill%3D%22%2364748b%22%3EBorrower%3C%2Ftext%3E%3Cline%20x1%3D%22205%22%20y1%3D%2262.5%22%20x2%3D%22237%22%20y2%3D%2262.5%22%20stroke%3D%22%2364748b%22%20stroke-width%3D%222%22%2F%3E%3Cpolygon%20points%3D%22244%2C62.5%20235%2C57.5%20235%2C67.5%22%20fill%3D%22%2364748b%22%2F%3E%3Crect%20x%3D%22245%22%20y%3D%2225%22%20width%3D%22170%22%20height%3D%2275%22%20rx%3D%2210%22%20fill%3D%22white%22%20stroke%3D%22%232563eb%22%20stroke-width%3D%222%22%2F%3E%3Ctext%20x%3D%22330%22%20y%3D%2258.5%22%20text-anchor%3D%22middle%22%20font-family%3D%22system-ui%2C-apple-system%2Csans-serif%22%20font-size%3D%2214%22%20font-weight%3D%22600%22%20fill%3D%22%230f172a%22%3ESells%20Treasuries%3C%2Ftext%3E%3Ctext%20x%3D%22330%22%20y%3D%2278.5%22%20text-anchor%3D%22middle%22%20font-family%3D%22system-ui%2C-apple-system%2Csans-serif%22%20font-size%3D%2211%22%20fill%3D%22%2364748b%22%3Ereceives%20%24100M%20cash%3C%2Ftext%3E%3Cline%20x1%3D%22420%22%20y1%3D%2262.5%22%20x2%3D%22452%22%20y2%3D%2262.5%22%20stroke%3D%22%2364748b%22%20stroke-width%3D%222%22%2F%3E%3Cpolygon%20points%3D%22459%2C62.5%20450%2C57.5%20450%2C67.5%22%20fill%3D%22%2364748b%22%2F%3E%3Crect%20x%3D%22460%22%20y%3D%2225%22%20width%3D%22170%22%20height%3D%2275%22%20rx%3D%2210%22%20fill%3D%22white%22%20stroke%3D%22%232563eb%22%20stroke-width%3D%222%22%2F%3E%3Ctext%20x%3D%22545%22%20y%3D%2258.5%22%20text-anchor%3D%22middle%22%20font-family%3D%22system-ui%2C-apple-system%2Csans-serif%22%20font-size%3D%2214%22%20font-weight%3D%22600%22%20fill%3D%22%230f172a%22%3EMMF%20B%3C%2Ftext%3E%3Ctext%20x%3D%22545%22%20y%3D%2278.5%22%20text-anchor%3D%22middle%22%20font-family%3D%22system-ui%2C-apple-system%2Csans-serif%22%20font-size%3D%2211%22%20fill%3D%22%2364748b%22%3ELender%3C%2Ftext%3E%3Cline%20x1%3D%22635%22%20y1%3D%2262.5%22%20x2%3D%22667%22%20y2%3D%2262.5%22%20stroke%3D%22%2364748b%22%20stroke-width%3D%222%22%2F%3E%3Cpolygon%20points%3D%22674%2C62.5%20665%2C57.5%20665%2C67.5%22%20fill%3D%22%2364748b%22%2F%3E%3Crect%20x%3D%22675%22%20y%3D%2225%22%20width%3D%22170%22%20height%3D%2275%22%20rx%3D%2210%22%20fill%3D%22white%22%20stroke%3D%22%232563eb%22%20stroke-width%3D%222%22%2F%3E%3Ctext%20x%3D%22760%22%20y%3D%2258.5%22%20text-anchor%3D%22middle%22%20font-family%3D%22system-ui%2C-apple-system%2Csans-serif%22%20font-size%3D%2214%22%20font-weight%3D%22600%22%20fill%3D%22%230f172a%22%3ERepurchases%3C%2Ftext%3E%3Ctext%20x%3D%22760%22%20y%3D%2278.5%22%20text-anchor%3D%22middle%22%20font-family%3D%22system-ui%2C-apple-system%2Csans-serif%22%20font-size%3D%2211%22%20fill%3D%22%2364748b%22%3Epays%20%24100.0139M%20next%20day%3C%2Ftext%3E%3Cline%20x1%3D%22850%22%20y1%3D%2262.5%22%20x2%3D%22882%22%20y2%3D%2262.5%22%20stroke%3D%22%2364748b%22%20stroke-width%3D%222%22%2F%3E%3Cpolygon%20points%3D%22889%2C62.5%20880%2C57.5%20880%2C67.5%22%20fill%3D%22%2364748b%22%2F%3E%3Crect%20x%3D%22890%22%20y%3D%2225%22%20width%3D%22170%22%20height%3D%2275%22%20rx%3D%2210%22%20fill%3D%22white%22%20stroke%3D%22%232563eb%22%20stroke-width%3D%222%22%2F%3E%3Ctext%20x%3D%22975%22%20y%3D%2258.5%22%20text-anchor%3D%22middle%22%20font-family%3D%22system-ui%2C-apple-system%2Csans-serif%22%20font-size%3D%2214%22%20font-weight%3D%22600%22%20fill%3D%22%230f172a%22%3EBank%20A%3C%2Ftext%3E%3Ctext%20x%3D%22975%22%20y%3D%2278.5%22%20text-anchor%3D%22middle%22%20font-family%3D%22system-ui%2C-apple-system%2Csans-serif%22%20font-size%3D%2211%22%20fill%3D%22%2364748b%22%3ECollateral%20returned%3C%2Ftext%3E%3C%2Fsvg%3E) *In a repo, the borrower sells securities for cash today and repurchases them at a higher price tomorrow — effectively a one-day collateralized loan.* In substance, it's a collateralized loan: - The "seller" is borrowing cash - The "buyer" is lending cash - The difference between the sale price and repurchase price is the interest - The securities serve as collateral **Example**: Bank A "sells" $100 million of US Treasury bonds to Money Market Fund B for $100 million cash. At the same time, both agree that Bank A will repurchase the bonds the next day for $100,013,889. The $13,889 is one day's interest at a 5% annual rate. From Bank A's perspective, this is overnight borrowing at 5% collateralized by Treasuries. From MMF B's perspective, this is a safe place to park cash overnight at 5%, secured by Treasury collateral. ## Why the Repo Market Exists ### Borrowers: Short-term funding need **Primary dealers** (major banks): Need cash to finance their securities positions. They hold huge inventories of bonds that must be financed daily. **Hedge funds**: Use repo to leverage their bond positions — buy $100M of bonds, finance them through repo, earn the spread between bond yield and repo rate. **Corporations**: Occasionally use repo to manage short-term cash needs. **Broker-dealers**: Match repo financing with customer positions. ### Lenders: Short-term investment of cash **Money market funds**: Hold $6+ trillion in cash; repo is a key vehicle for deploying this cash safely. **Corporations**: Companies with large cash balances (Apple, Microsoft historically) have deployed cash into repo. **Central banks**: Foreign central banks holding USD reserves lend them via repo. **Securities lenders**: Agents lending securities from pension fund portfolios get reinvested cash, often deployed into repo. ## Repo Types ### 1. Overnight Repo ![The five main repo structures differ by duration, settlement mechanism, and collateral specificity.](data:image/svg+xml,%3Csvg%20xmlns%3D%22http%3A%2F%2Fwww.w3.org%2F2000%2Fsvg%22%20viewBox%3D%220%200%20760%20211%22%20width%3D%22760%22%20height%3D%22211%22%20role%3D%22img%22%3E%3Ctitle%3EHierarchy%3C%2Ftitle%3E%3Crect%20width%3D%22100%25%22%20height%3D%22100%25%22%20fill%3D%22%23f8fafc%22%2F%3E%3Crect%20x%3D%22300%22%20y%3D%2220%22%20width%3D%22160%22%20height%3D%2258%22%20rx%3D%228%22%20fill%3D%22%232563eb%22%2F%3E%3Ctext%20x%3D%22380%22%20y%3D%2254%22%20text-anchor%3D%22middle%22%20font-family%3D%22system-ui%2C-apple-system%2Csans-serif%22%20font-size%3D%2214%22%20font-weight%3D%22700%22%20fill%3D%22white%22%3ERepo%20Types%3C%2Ftext%3E%3Cpath%20d%3D%22M%20380%2078%20L%20380%20105.5%20L%20110%20105.5%20L%20110%20133%22%20stroke%3D%22%23cbd5e1%22%20stroke-width%3D%222%22%20fill%3D%22none%22%2F%3E%3Crect%20x%3D%2230%22%20y%3D%22133%22%20width%3D%22160%22%20height%3D%2258%22%20rx%3D%228%22%20fill%3D%22white%22%20stroke%3D%22%230891b2%22%20stroke-width%3D%222%22%2F%3E%3Ctext%20x%3D%22110%22%20y%3D%22158%22%20text-anchor%3D%22middle%22%20font-family%3D%22system-ui%2C-apple-system%2Csans-serif%22%20font-size%3D%2213%22%20font-weight%3D%22600%22%20fill%3D%22%230f172a%22%3EOvernight%3C%2Ftext%3E%3Ctext%20x%3D%22110%22%20y%3D%22176%22%20text-anchor%3D%22middle%22%20font-family%3D%22system-ui%2C-apple-system%2Csans-serif%22%20font-size%3D%2210%22%20fill%3D%22%2364748b%22%3E1-day%2C%20most%20common%3C%2Ftext%3E%3Cpath%20d%3D%22M%20380%2078%20L%20380%20105.5%20L%20290%20105.5%20L%20290%20133%22%20stroke%3D%22%23cbd5e1%22%20stroke-width%3D%222%22%20fill%3D%22none%22%2F%3E%3Crect%20x%3D%22210%22%20y%3D%22133%22%20width%3D%22160%22%20height%3D%2258%22%20rx%3D%228%22%20fill%3D%22white%22%20stroke%3D%22%230891b2%22%20stroke-width%3D%222%22%2F%3E%3Ctext%20x%3D%22290%22%20y%3D%22158%22%20text-anchor%3D%22middle%22%20font-family%3D%22system-ui%2C-apple-system%2Csans-serif%22%20font-size%3D%2213%22%20font-weight%3D%22600%22%20fill%3D%22%230f172a%22%3ETerm%3C%2Ftext%3E%3Ctext%20x%3D%22290%22%20y%3D%22176%22%20text-anchor%3D%22middle%22%20font-family%3D%22system-ui%2C-apple-system%2Csans-serif%22%20font-size%3D%2210%22%20fill%3D%22%2364748b%22%3E1%20week%E2%80%936%20months%3C%2Ftext%3E%3Cpath%20d%3D%22M%20380%2078%20L%20380%20105.5%20L%20470%20105.5%20L%20470%20133%22%20stroke%3D%22%23cbd5e1%22%20stroke-width%3D%222%22%20fill%3D%22none%22%2F%3E%3Crect%20x%3D%22390%22%20y%3D%22133%22%20width%3D%22160%22%20height%3D%2258%22%20rx%3D%228%22%20fill%3D%22white%22%20stroke%3D%22%230891b2%22%20stroke-width%3D%222%22%2F%3E%3Ctext%20x%3D%22470%22%20y%3D%22158%22%20text-anchor%3D%22middle%22%20font-family%3D%22system-ui%2C-apple-system%2Csans-serif%22%20font-size%3D%2213%22%20font-weight%3D%22600%22%20fill%3D%22%230f172a%22%3EOpen%3C%2Ftext%3E%3Ctext%20x%3D%22470%22%20y%3D%22176%22%20text-anchor%3D%22middle%22%20font-family%3D%22system-ui%2C-apple-system%2Csans-serif%22%20font-size%3D%2210%22%20fill%3D%22%2364748b%22%3ENo%20fixed%20end%20date%3C%2Ftext%3E%3Cpath%20d%3D%22M%20380%2078%20L%20380%20105.5%20L%20650%20105.5%20L%20650%20133%22%20stroke%3D%22%23cbd5e1%22%20stroke-width%3D%222%22%20fill%3D%22none%22%2F%3E%3Crect%20x%3D%22570%22%20y%3D%22133%22%20width%3D%22160%22%20height%3D%2258%22%20rx%3D%228%22%20fill%3D%22white%22%20stroke%3D%22%230891b2%22%20stroke-width%3D%222%22%2F%3E%3Ctext%20x%3D%22650%22%20y%3D%22158%22%20text-anchor%3D%22middle%22%20font-family%3D%22system-ui%2C-apple-system%2Csans-serif%22%20font-size%3D%2213%22%20font-weight%3D%22600%22%20fill%3D%22%230f172a%22%3ETri-Party%3C%2Ftext%3E%3Ctext%20x%3D%22650%22%20y%3D%22176%22%20text-anchor%3D%22middle%22%20font-family%3D%22system-ui%2C-apple-system%2Csans-serif%22%20font-size%3D%2210%22%20fill%3D%22%2364748b%22%3ECustodian%20settles%3C%2Ftext%3E%3C%2Fsvg%3E) *The five main repo structures differ by duration, settlement mechanism, and collateral specificity.* The most common — borrow cash today, repay tomorrow. Overnight repo rates are among the most watched rates in finance. ### 2. Term Repo Multi-day agreement (1 week to 6 months typically). Used for more stable financing. ### 3. Open Repo Indefinite term — either party can terminate any day. Rate resets daily. ### 4. Tri-Party Repo Settled through a third-party custodian (BNY Mellon in US). The custodian handles securities movement, valuation, and margin calls. Tri-party repo is the standard for most institutional repo. ### 5. GC (General Collateral) Repo vs. Special Repo **General Collateral (GC)**: Any Treasury security of the agreed type can serve as collateral. Most repo is GC. **Special repo**: A specific security is needed (e.g., the 10-year on-the-run Treasury). Repo rates may be significantly below GC rates ("going special") when the security is in high demand for shorting. ## The Haircut The **haircut** (margin) is the discount applied to securities used as collateral: **Example with haircut**: - Securities market value: $100 million - Haircut: 2% - Cash borrowed: $98 million - Buyer receives $100M of securities but advances only $98M cash **Haircut protects the lender** against collateral price decline before maturity. If Bank A defaults overnight and Treasury prices have dropped, MMF B can sell the collateral for less than $100M but still recover the $98M cash they lent. **Typical haircuts**: - US Treasuries: 0.5-3% (lowest risk, smallest haircut) - Agency MBS: 2-5% - Investment grade corporate bonds: 5-10% - High yield bonds: 10-20%+ - Equities (for prime brokerage repo): 15-25% **Haircut dynamics in crises**: In 2008, dealers sharply raised haircuts on private-label MBS from 3-5% to 25%+ — effectively making that collateral unusable in repo. This "margin call on the system" was a key transmission mechanism of the crisis. ## The Repo Rate The repo rate is the interest rate implied by the difference between the sale and repurchase prices: **Repo rate** = (Repurchase Price / Sale Price − 1) × 360/days **Example**: Sell for $100M, repurchase for $100.0014M in 1 day: - Repo rate = (0.0014 / 100) × 360 = 0.504% annualized **Factors affecting repo rates**: - Federal funds rate (overnight is closely tied) - Collateral quality (Treasuries < Agencies < corporates) - Supply-demand balance for cash - Quarter-end dynamics (banks reduce balance sheet, repo rates spike) - Year-end pressures ## SOFR: The Benchmark **SOFR (Secured Overnight Financing Rate)** is the leading benchmark rate derived from repo market transactions. Published by the [Federal Reserve](https://www.federalreserve.gov/) Bank of New York since 2018, SOFR has replaced LIBOR as the reference rate for most USD financial contracts: - Based on daily volume-weighted median of overnight Treasury repo transactions - Transaction volume typically $1-2 trillion per day - Used as reference rate for trillions in derivatives, bond issuance, loans **SOFR replaced LIBOR** (which was discontinued June 30, 2023) because LIBOR was based on submissions from a panel of banks (manipulable) rather than actual transactions. SOFR uses real transactions in a deep market. ## The September 2019 Repo Spike On September 17, 2019, overnight repo rates spiked from ~2.2% to 10% intraday — a massive disruption that required immediate Federal Reserve intervention. ![On September 17, 2019, overnight repo rates spiked nearly 5x above normal as cash demand overwhelmed supply.](data:image/svg+xml,%3Csvg%20xmlns%3D%22http%3A%2F%2Fwww.w3.org%2F2000%2Fsvg%22%20viewBox%3D%220%200%20800%20210%22%20width%3D%22800%22%20height%3D%22210%22%20role%3D%22img%22%3E%3Ctitle%3EComparison%3C%2Ftitle%3E%3Crect%20width%3D%22100%25%22%20height%3D%22100%25%22%20fill%3D%22%23f8fafc%22%2F%3E%3Ctext%20x%3D%22230%22%20y%3D%2257.5%22%20text-anchor%3D%22end%22%20font-family%3D%22system-ui%2C-apple-system%2Csans-serif%22%20font-size%3D%2214%22%20font-weight%3D%22600%22%20fill%3D%22%230f172a%22%3ENormal%20Rate%3C%2Ftext%3E%3Crect%20x%3D%22240%22%20y%3D%2225%22%20width%3D%2299.00000000000001%22%20height%3D%2255%22%20rx%3D%226%22%20fill%3D%22%232563eb%22%2F%3E%3Ctext%20x%3D%22351%22%20y%3D%2257.5%22%20font-family%3D%22system-ui%2C-apple-system%2Csans-serif%22%20font-size%3D%2214%22%20font-weight%3D%22700%22%20fill%3D%22%232563eb%22%3E%252.2%3C%2Ftext%3E%3Ctext%20x%3D%22230%22%20y%3D%22152.5%22%20text-anchor%3D%22end%22%20font-family%3D%22system-ui%2C-apple-system%2Csans-serif%22%20font-size%3D%2214%22%20font-weight%3D%22600%22%20fill%3D%22%230f172a%22%3ESpike%20Rate%3C%2Ftext%3E%3Crect%20x%3D%22240%22%20y%3D%22120%22%20width%3D%22450%22%20height%3D%2255%22%20rx%3D%226%22%20fill%3D%22%237c3aed%22%2F%3E%3Ctext%20x%3D%22702%22%20y%3D%22152.5%22%20font-family%3D%22system-ui%2C-apple-system%2Csans-serif%22%20font-size%3D%2214%22%20font-weight%3D%22700%22%20fill%3D%22%237c3aed%22%3E%2510%3C%2Ftext%3E%3C%2Fsvg%3E) *On September 17, 2019, overnight repo rates spiked nearly 5x above normal as cash demand overwhelmed supply.* **Causes**: - Corporate tax payment date drained cash from money market - Treasury debt issuance absorbed cash - Banks' reserves had fallen due to balance sheet runoff - Effectively, more demand for cash than available supply **Fed response**: - NY Fed began daily overnight repo operations (lending cash against Treasury collateral) - Eventually expanded to term repo operations - Over $100 billion provided daily at peak **Lesson**: The repo market can unexpectedly tighten when reserves fall below a threshold that banks require for normal operations. The Fed must maintain adequate reserves in the system. ## The March 2020 Repo Crisis When COVID panic hit in March 2020: - Investors rushed to cash; Treasury prices plunged (yields spiked) as forced selling occurred - Repo market showed stress — especially for specific Treasury securities - Fed conducted enormous repo operations (up to $1 trillion) - Also launched "Quantitative Easing" buying Treasuries outright The Standing Repo Facility (SRF) was later established as a permanent mechanism to provide liquidity on demand — lessons learned. ## Repo in Monetary Policy The Fed conducts monetary policy through: **Open Market Operations**: Historically, outright purchases/sales of Treasuries. Today, more often through repo. **Overnight Repo (ON RRP)**: The Fed "borrows" from money market funds through reverse repo, placing a floor on money market rates. Counter-party to trillions in MMF cash. **Overnight Repo Facility (SRF)**: Lends to primary dealers at a fixed rate, placing a ceiling on overnight rates. **IORB (Interest on Reserve Balances)**: Rate paid on bank reserves, part of the target rate corridor. ## Repo vs. Reverse Repo These are **the same transaction viewed from different sides**: - Party A "sells securities now, buys back later" = doing a **repo** (borrowing) - Party B "buys securities now, sells back later" = doing a **reverse repo** (lending) Every repo has both a repo and reverse repo counterparty. It's one transaction — two perspectives. **Fed terminology**: - Fed lending cash (taking securities as collateral): Called a "repo" from the Fed's perspective as lender - Fed borrowing cash (giving securities as collateral, i.e., draining cash from the system): Called "reverse repo" or "ON RRP" ## Risks in the Repo Market **Counterparty risk**: If the other party defaults before repurchase, you're left with (potentially illiquid) collateral instead of cash. **Collateral price risk**: Between the sale and repurchase, collateral value can change. Mitigated by haircuts and margin calls. **Settlement risk**: Operational risk of a failed settlement. **[Rehypothecation](/blog/rehypothecation) risk**: Dealers often reuse collateral in other trades (rehypothecation). If the dealer fails, recovery of the original securities can be complicated — an issue during the 2008 Lehman collapse. **Systemic risk**: The repo market's size and interconnection mean disruptions propagate quickly. Regulators closely monitor daily repo market functioning. ## Authoritative Sources For deeper background and primary-source data on this topic, the following authoritative sources are useful starting points: - [IRS](https://www.irs.gov/) - [SEC](https://www.sec.gov/) ## Conclusion The repo market is the lubricant of the global financial system — moving trillions of dollars daily in short-term collateralized loans that finance securities positions, deploy cash, and transmit monetary policy. For investors, repo rates signal short-term funding conditions and credit stress. For regulators, repo market functioning is critical to financial stability — which is why the Fed has multiple tools (ON RRP, SRF, discount window) to ensure the market operates smoothly. Understanding repo mechanics is essential for making sense of monetary policy, money market funds, and bank funding costs. For related fixed income and money market topics, see our guides on [weighted average maturity](/blog/weighted-average-maturity), [credit default swap](/blog/credit-default-swap), and [ALCO (asset-liability committee)](/blog/alco-definition). Warren at [heywarren.com](https://heywarren.com) helps you understand short-term rates, money market conditions, and their impact on your cash and fixed income investments. --- ## Related Reading **More from Warren**: **Authoritative sources**: - [SEC Investor.gov — Investing Basics](https://www.investor.gov/introduction-investing/investing-basics) - [FINRA — Investor Education](https://www.finra.org/investors)