The risk-free rate is the theoretical return on an investment with zero chance of loss, and it sets the baseline that nearly every other financial calculation builds on. In practice, analysts use the yield on U.S. Treasury securities as the stand-in, most often the 10-year Treasury note, which sits around 4.22% as of early 2026. That single number ripples through mortgage pricing, corporate borrowing costs, stock valuations, pension funding, and even the damages awarded in court cases.
Why It’s Called Theoretical
No real investment is truly free of risk. A genuinely risk-free asset would have to eliminate three things at once: default risk (the borrower can’t pay), reinvestment risk (interim cash flows can’t be reinvested at the same rate), and liquidity risk (your money isn’t accessible without a haircut). Nothing on the market clears all three.
The closest approximation is sovereign debt from a government that can tax its citizens and, in extremis, print its own currency. That revenue-generating power is what separates a Treasury security from a corporate bond. A company can go bankrupt. The federal government, in theory, cannot. Financial models treat the gap between that reality and true zero risk as small enough to ignore, so Treasury yields stand in for the ideal.
Which Treasury Yield to Use
The Treasury issues three main categories of marketable debt, and the right one depends on the time horizon you’re measuring.
- Treasury bills mature in 4, 8, 13, 17, 26, or 52 weeks. They’re sold at a discount to face value and pay no coupon; your return is the gap between purchase price and maturity value.1TreasuryDirect. Treasury Bills
- Treasury notes mature in 2, 3, 5, 7, or 10 years and pay interest every six months.2TreasuryDirect. Treasury Notes
- Treasury bonds run 20 or 30 years, also paying semiannual interest, and serve as the reference for long-duration obligations like pensions and infrastructure finance.
Yields are set at regular Treasury auctions through competitive bidding among institutional investors and primary dealers, and the resulting rates are published daily.3TreasuryDirect. Announcements, Data and Results
Of all these, the 10-year note gets the most attention. It anchors mortgage rates, shapes corporate bond pricing, and functions as the default risk-free rate in most equity valuation work. When commentary talks about “yields rising,” the 10-year is almost always what’s meant. Shorter maturities tend to show up in models with shorter cash-flow horizons; the 30-year surfaces when the obligation itself runs that long.
Nominal vs. Real Risk-Free Rates
The yield quoted on a Treasury is a nominal rate. It tells you how many dollars you’ll earn, not what those dollars will buy. The real risk-free rate strips out expected inflation to show the actual gain in purchasing power. The Fisher Equation captures the relationship in rough form: nominal rate ≈ real rate + expected inflation. If a Treasury note yields 4.5% and inflation runs 3%, the real return is roughly 1.5%.
Treasury Inflation-Protected Securities (TIPS) provide a direct read on the real rate. The principal adjusts with the Consumer Price Index, so the quoted TIPS yield already reflects an inflation-adjusted return.4TreasuryDirect. Treasury Inflation-Protected Securities (TIPS) The spread between a conventional Treasury and a TIPS of the same maturity is the “breakeven inflation rate,” which tells you what the bond market expects inflation to average over that period.
When Real Rates Go Negative
Negative real rates happen when inflation outpaces the nominal yield on safe assets. That environment persisted for long stretches after the 2008 financial crisis and returned in 2021-2022 when inflation surged past short-term Treasury yields. In those conditions, holding T-bills means losing purchasing power even as your account balance grows. The effect is a penalty on savers and a quiet subsidy for borrowers, and it tends to push capital toward riskier assets like stocks and real estate because safe assets guarantee a real loss.
Where the Rate Shows Up in Practice
The risk-free rate isn’t an academic abstraction. It’s a load-bearing input in the formulas used to price stocks, value businesses, measure pension liabilities, and calculate court damages. Small changes in the rate translate into large swings in all of these numbers.
CAPM and Equity Valuations
The Capital Asset Pricing Model calculates the expected return on a stock as the risk-free rate plus the stock’s beta times the market risk premium. The risk-free rate is the floor. When it rises, every equity’s required return rises with it, which tends to pull stock prices down. When it falls, valuations expand. The market risk premium, representing the extra return investors demand for holding stocks over Treasuries, has historically averaged somewhere in the 4% to 6% range for U.S. equities, with estimates varying by methodology and period.
Discounted Cash Flow
In a DCF model, future cash flows are discounted to present value using a rate that reflects the time value of money plus the risk of the cash flows themselves. The risk-free rate is the base layer. A higher base means future earnings are worth less today, which directly lowers what a buyer should rationally pay for a business. The inflated valuations of 2010-2021 were partly a mechanical consequence of near-zero discount rates making distant cash flows look unusually valuable.
Pension Liabilities
For single-employer defined benefit plans, the rate used to value liabilities has direct regulatory consequences. Under IRC Section 430(h)(2), plan actuaries use three segment rates based on 24-month averages of corporate bond yields to calculate the present value of future benefits. For plan years beginning in 2026, the applicable minimum is 95% and the applicable maximum is 105% of those averages, and the adjusted segment rates run from roughly 4.75% at the first segment to about 5.7% at the third.5Internal Revenue Service. Pension Plan Funding Segment Rates When rates rise, liabilities shrink and plans look better funded; when rates fall, liabilities balloon and employer contribution requirements can jump.
Legal Damages and Business Valuations in Court
Courts routinely use Treasury yields when they need a discount rate. In wrongful death and personal injury cases, an expert may project decades of lost wages and then discount them to present value using a Treasury-linked rate. A lower discount rate produces a higher present value, which is why the choice of maturity and whether to add any risk premium are frequently contested. Business valuations in divorce proceedings and shareholder disputes work similarly: the risk-free rate feeds into the discount rate applied to a company’s expected future profits, and a half-percentage-point difference can move a valuation by millions. There’s no uniformly mandated maturity. Some experts match the rate to the expected loss period; others default to the 10-year yield as a broadly accepted middle ground.
When “Risk-Free” Isn’t Quite
The assumption that U.S. Treasuries carry zero default risk took a public hit in May 2025, when Moody’s downgraded the U.S. government’s long-term credit rating from Aaa to Aa1, citing the trajectory of federal debt and fiscal deficits.6Moody’s Ratings. 2025 United States Sovereign Rating Action That made the downgrade unanimous across the three major rating agencies. S&P had already downgraded in 2011, and Fitch followed in 2023.
Market reactions have been inconsistent. After S&P’s 2011 downgrade, investors bought more Treasuries in a flight to safety, and the 10-year yield fell roughly 50 basis points. After Fitch’s 2023 downgrade, yields moved the other way, rising about 19 basis points. The prevailing inflation environment, global demand for dollar-denominated assets, and the lack of comparable alternatives all shape how the market responds in any given cycle.
For modeling purposes, most analysts still treat U.S. Treasuries as the risk-free benchmark. The reasoning is pragmatic. Even at Aa1, U.S. government debt remains among the highest-rated sovereign obligations in the world, and nothing matches its liquidity or market depth. The repeated downgrades are a useful reminder, though, that “risk-free” is a simplification the math leans on, not a description of reality.