Secured Overnight Financing Rate

What Is the Secured Overnight Financing Rate?

The Secured Overnight Financing Rate (SOFR) is the benchmark interest rate for overnight cash borrowing collateralized by U.S. Treasury securities. It was developed as a replacement for LIBOR and is now the cornerstone of U.S. dollar interest rate markets.

This entry serves as a cross-reference to the detailed SOFR glossary term, which covers the rate's calculation methodology, market applications, and role in the LIBOR transition. The two names refer to the identical rate.

Why It Matters for Markets

The Secured Overnight Financing Rate matters because it is the base rate from which virtually all U.S. dollar variable-rate financial products are now priced. Whether you are a homeowner with an adjustable-rate mortgage, a corporation with a revolving credit facility, or a derivatives trader managing an interest rate swap book, SOFR is the reference point that determines your interest payments.

The rate's behavior reflects conditions in the U.S. Treasury repo market, the largest short-term funding market in the world. Daily SOFR movements of a few basis points are normal, but larger moves can signal shifts in funding conditions, collateral scarcity, or broader financial stress.

Because SOFR is a secured (collateralized) rate, it excludes bank credit risk. This is a deliberate design choice that makes SOFR more stable and resistant to financial sector stress than LIBOR was. During banking stress events, SOFR may actually decline (as investors flee to the safety of Treasury collateral) while bank funding costs spike.

SOFR in the Monetary Policy Framework

SOFR operates within the Federal Reserve's monetary policy implementation framework. The Fed's Interest on Reserve Balances (IORB) rate and the Overnight Reverse Repo (ON RRP) facility rate effectively create a corridor within which SOFR trades. The ON RRP rate acts as a floor (since MMFs can always park cash at the Fed), while IORB acts as a ceiling (since banks can earn this rate on reserves without entering the repo market).

Understanding this framework helps explain SOFR's day-to-day behavior and its relationship to other short-term rates. It also explains why the Fed's administrative rate settings are so important for the transmission of monetary policy through the financial system.