SOFR

SOFR is the Secured Overnight Financing Rate, the benchmark interest rate for dollar-denominated repurchase-agreement (repo) transactions, published daily by the New York Fed. SOFR replaced US dollar LIBOR as the primary benchmark for floating-rate loans, derivatives, and corporate financings effective June 2023, when LIBOR was officially retired. The rate reflects the cost of borrowing cash overnight collateralized by Treasury securities.

Why it matters: SOFR is the foundational rate for trillions of dollars of floating-rate debt across corporate loans, leveraged loans, derivatives, and structured products. It trades within the Fed funds target range and typically prints a few basis points above the overnight reverse-repo rate (RRP) and below the Fed funds rate. SOFR is more representative of the actual cost of dollar funding than the old LIBOR (which was an unsecured-bank-quote average) because it is based on actual transactions in the largest US money market.

SOFR is trading near 3.63% in April 2026, well within the 3.50-3.75% Fed funds target range. The April 29 Fed hold (8-4 dissent, four wanting cuts) keeps SOFR roughly stable; any 25bp Fed move translates almost immediately into SOFR. Quarter-end and year-end repo-market dislocations occasionally push SOFR above the IOER ceiling (the upper bound of the target range) by 5-15bp on stress days, but these spikes typically fade within hours.

The structural backdrop is post-QT, with the Fed running a "maintenance" balance-sheet policy after halting QT in mid-2025. Bank reserves at $3.0-$3.2 trillion are adequate but not abundant; the RRP is near depleted at sub-$100 billion versus the 2023 peak above $2.5 trillion. This means SOFR is more responsive to liquidity conditions than during the 2021-2022 abundant-reserves regime. Watch year-end and Treasury settlement dates for repo-market stress.

Modern SOFR range: 0.01% in 2020-2021 (zero-rate era), 5.40% peak in 2023 (Fed funds 5.25-5.50%), 3.63% in April 2026. Notable stress events: September 17, 2019 spiked to 5.25% intraday on a quarter-end Treasury settlement plus corporate tax day combination, well above the 2.10% Fed funds target; the Fed responded by restarting repo operations and Treasury bill purchases. The drivers are Fed funds (mechanical), reserve abundance (RRP and bank-reserve levels), and Treasury supply (heavy bill issuance can lift SOFR via demand for collateral).

First, the SOFR-IOER spread. Sustained SOFR above IOER signals reserve scarcity; persistent below-IOER prints signal abundance. The current spread is near zero, indicating balanced conditions.

Second, RRP balance and bank-reserve levels. RRP near depletion plus reserves below $3 trillion would raise the probability of repo-market stress and force a Fed response (similar to 2019).

Third, end-of-quarter and end-of-year repo conditions. Any sustained year-end SOFR spike above target range upper bound would force the Fed to consider a standing repo facility expansion.