TED Spread
The TED Spread is the difference between the three-month LIBOR rate (the rate at which banks historically lent to each other unsecured) and the three-month U.S. Treasury bill yield, historically serving as a measure of perceived credit risk and stress in the global banking system relative to the risk-free rate.
The name TED Spread derives from T-Bill (Treasury) and ED (Eurodollar futures, which historically tracked LIBOR). In its most commonly cited form, the TED Spread measured the gap between what it cost banks to borrow from each other for three months in the unsecured interbank market (reflected in three-month LIBOR) and what the U.S. government paid to borrow for three months (the three-month Treasury bill yield). This difference captured a fundamental dimension of systemic financial risk: if banks trust each other, they will lend to each other at rates close to the risk-free government rate, keeping the TED Spread narrow. If banks grow concerned about counterparty risk — about whether the institution borrowing from them might default — they demand a higher rate, widening the TED Spread.
In normal financial conditions, the TED Spread historically traded in a range of approximately 10 to 50 basis points. During periods of financial stress, it could widen dramatically. The most famous historical example was the 2008 Global Financial Crisis: as the collapse of Lehman Brothers in September 2008 triggered acute interbank counterparty fears, the TED Spread spiked to over 460 basis points — levels not seen since the early 1980s savings and loan crisis. This extreme widening reflected a near-complete breakdown in interbank trust; banks were essentially charging each other rates approaching those of distressed corporate borrowers to lend unsecured.
The TED Spread also widened sharply during the 1987 stock market crash, the 1998 Long-Term Capital Management crisis, the bursting of the dot-com bubble in 2000-2001, and the early stages of the COVID-19 crisis in March 2020. In each case, elevated TED Spread readings historically corresponded with periods of heightened stress in the financial plumbing of the U.S. and global monetary system.
The TED Spread lost much of its analytical relevance following the phase-out of LIBOR as a benchmark rate. LIBOR, which had historically served as the global benchmark for unsecured interbank borrowing, was discontinued by most tenors by mid-2023 and replaced by alternative reference rates such as SOFR (Secured Overnight Financing Rate) in the United States. The SOFR-based counterpart to the TED Spread uses the difference between SOFR-linked term rates and Treasury bill yields, though its behavioral history is much shorter than the decades-long LIBOR-based TED Spread record.
For students of monetary policy and financial history, the TED Spread is an important concept because it illustrates how credit markets can fracture under stress. The gap between what safe borrowers (the U.S. government) and less-safe borrowers (banks) pay to borrow in short-term markets is a direct measure of the perceived riskiness of the financial system at any given moment — one of the most fundamental readings available to macro analysts.