The 10-year yield gained 1.10 points in 2026. Inflation pricing: 0.11
From December 31, 2025 to October 2, 2026 the 10-year breakeven moved from 2.25% to 2.36%. The real yield did the rest. CPI ran at 3.4%.
- What happened
- On October 2, 2026 the 10-year Treasury par yield was 5.28% and the 10-year TIPS par real yield 2.92%, leaving a 10-year breakeven inflation rate of 2.36%. On December 31, 2025 the same three figures were 4.18%, 1.93% and 2.25%.
- Why
- Breakeven is the nominal yield minus the real yield on a TIPS of the same maturity. TIPS principal is indexed to unadjusted CPI-U, so the gap is the inflation rate at which the two bonds pay the same. It also contains an inflation risk premium and a TIPS liquidity premium, which is why it is not a pure measure of expectations.
- The numbers that matter
- 2.36%10-year breakeven, October 2, 2026 (FRED T10YIE)2.35%5-year, 5-year forward rate, October 2, 2026 (FRED T5YIFR)+0.99Points added to the 10-year real yield, Dec 31, 2025 to Oct 2, 20263.4%CPI, 12 months to August 2026 (BLS, Sep 11, 2026)
- Why it matters
- The breakeven is the line that decides whether a 10-year TIPS or an ordinary 10-year Treasury bought on a given day ends up paying more. It also shows that most of the 2026 rise in borrowing costs came from real yields, not inflation pricing.
- What happens nextas we saw it on 7 Oct 2026
- The Bureau of Labor Statistics publishes the September 2026 CPI on October 14, 2026 at 8:30 a.m. ET. Treasury publishes both par yield curves every business day.
Of the 1.10-point rise in the 10-year nominal yield, 0.99 points came from the real yield and 0.11 from breakeven inflation.
| 10-year nominal yield (4.18% to 5.28%) | 1.1 |
|---|---|
| 10-year TIPS real yield (1.93% to 2.92%) | 0.99 |
| 10-year breakeven (2.25% to 2.36%) | 0.11 |
Between December 31, 2025 and October 2, 2026 the yield on the 10-year Treasury note rose from 4.18% to 5.28%, according to Treasury's daily par yield curve. Very little of that rise came from the part of the yield that pays for inflation. The 10-year breakeven inflation rate, the gap between the ordinary 10-year yield and the yield on 10-year Treasury Inflation-Protected Securities, moved from 2.25% to 2.36%. The real yield did the rest, climbing from 1.93% to 2.92%.
Over the same months, prices ran faster than that 2.36%. The Consumer Price Index rose 3.4% in the 12 months to August 2026, the Bureau of Labor Statistics reported on September 11, 2026. This piece explains how the breakeven is built, what the inflation-linked bond behind it promises, and why the Federal Reserve's own economists treat it as something other than a prediction.
One subtraction, two Treasury curves
Treasury publishes two daily curves from the same 3:30 p.m. market quotes. One prices ordinary notes and bonds, whose coupons and principal are fixed in dollars. The other prices TIPS, whose principal rises and falls with consumer prices. The difference between the two at the same maturity is the breakeven.
Treasury builds its par yield curve from closing bid prices on the newest Treasury notes and bonds, and its par real curve, which relates “the par real yield on a Treasury Inflation Protected Security (TIPS) to its time to maturity”, from the newest TIPS. For both, the input prices are “indicative quotations obtained by the Federal Reserve Bank of New York at approximately 3:30 PM each business day.”
10-year: nominal par yield 5.28% − TIPS par real yield 2.92% = 2.36%.
5-year: nominal 5.06% − real 2.69% = 2.37%.
FRED, the St. Louis Fed's database, published exactly 2.36% (T10YIE) and 2.37% (T5YIE) for October 2, 2026. Its notes say the 10-year series is derived from the 10-year constant-maturity yield and the 10-year inflation-indexed constant-maturity yield, with data obtained directly from Treasury since June 21, 2019.
Subtraction is a convention, not exact arithmetic. Compounded properly, 5.28% nominal against 2.92% real implies 1.0528 ÷ 1.0292 − 1, or 2.29%. FRED's series use the simple difference, so that is the number quoted here.
The forward rate strips out the next five years
FRED describes T5YIFR as average expected inflation over the five-year period that begins five years after the observation date, and publishes its formula: take the 10-year breakeven compounded over ten years, divide by the 5-year breakeven compounded over five, and take the fifth root. With the October 2, 2026 inputs: ((1.023610 ÷ 1.02375)1/5 − 1) = 2.35%, the figure FRED published for that date. With the December 31, 2025 inputs (2.25% and 2.26%), the same formula gives 2.24%.
The forward rate is built to look past whatever is happening to prices in the first five years. Between the last day of 2025 and October 2, 2026, it moved by 0.11 points, the same as the 10-year breakeven.
What a TIPS actually promises
The breakeven means something only because of the contract behind the real yield. Treasury's auction regulations, 31 CFR Part 356, set it out.
The regulation defines the index as “the monthly non-seasonally adjusted U.S. City Average All Items Consumer Price Index for All Urban Consumers, published by the Bureau of Labor Statistics”. The Reference CPI for the first day of a month is the CPI for the third preceding calendar month, interpolated for days in between. Inflation-adjusted principal is the par amount multiplied by an index ratio, the Reference CPI on a date divided by the Reference CPI on the issue date. Semiannual interest is one-half of the fixed annual rate times that adjusted principal.
TIPS notes and bonds “are redeemed at maturity at their inflation-adjusted principal, or at their par amount, whichever is greater” (31 CFR 356.5). If adjusted principal is below par at maturity, Treasury “will pay an additional amount so that the additional amount plus the inflation-adjusted principal equals the par amount” (31 CFR 356.30).
If the Reference CPI rises 3.4% between issue and a later date, matching the 12-month CPI change to August 2026, the index ratio is 1.034 and $1,000 of par becomes $1,034 of inflation-adjusted principal. The fixed coupon is then paid on $1,034, not $1,000.
So a nominal note pays a known number of dollars, and a TIPS pays a known real return plus whatever CPI-U turns out to be. If CPI-U averages exactly the breakeven rate over the life of the two bonds, they come out roughly level. That is where the name comes from.
Why breakeven is not a forecast
The Federal Reserve Board's own researchers are careful with the word “expectations”. In a FEDS Notes paper published on May 21, 2019, Don Kim, Cait Walsh and Min Wei call the spread “inflation compensation” and break it into parts.
TIPS inflation compensation (IC)—defined as the nominal yield minus the TIPS yield—can be decomposed into three components, TIPS IC = expected inflation + inflation risk premium – TIPS liquidity premium.Kim, Walsh and Wei, “Tips from TIPS: Update and Discussions”, FEDS Notes, Board of Governors of the Federal Reserve System, May 21, 2019
The inflation risk premium, in the authors' words, “is the extra compensation nominal bond investors demand for bearing inflation risks.” The TIPS liquidity premium “is not connected to inflation risk but rather reflects factors that drive a wedge between TIPS yields and true real yields.” They note that it “was high when TIPS was first launched” and surged again in the 2008–2009 financial crisis, as investors “sought the safety and liquidity of nominal Treasury securities.”
From the equation, a positive inflation risk premium lifts the breakeven above expected inflation, and a liquidity premium on TIPS pulls it below. Neither premium is published as a market price; both have to be estimated with a model. A change in the breakeven can therefore come from a change in expectations, a change in either premium, or both, and the spread alone cannot say which.
The authors put it plainly: the spread “is an imperfect measure, as it contains other components that can drive a wedge between inflation compensation and market participants' true inflation expectations.”
Set against actual inflation and the 5% yield
| Measure | Dec 31, 2025 | Sep 15, 2026 | Oct 2, 2026 |
|---|---|---|---|
| 10-year nominal par yield | 4.18% | 5.00% | 5.28% |
| 10-year TIPS par real yield | 1.93% | 2.62% | 2.92% |
| 10-year breakeven | 2.25% | 2.38% | 2.36% |
| 5-year nominal par yield | 3.73% | 4.83% | 5.06% |
| 5-year TIPS par real yield | 1.47% | 2.42% | 2.69% |
| 5-year breakeven | 2.26% | 2.41% | 2.37% |
| 5-year, 5-year forward | 2.24% | 2.35% | 2.35% |
The CPI rose 3.4% over the 12 months to August 2026, and 2.4% excluding food and energy, the Bureau of Labor Statistics reported on September 11, 2026. Headline CPI is the same all-items index that TIPS principal is tied to, though TIPS use the unadjusted series.
Headline CPI for the 12 months to August 2026 minus the 10-year breakeven on October 2, 2026: 3.4% − 2.36% = 1.04 points.
The 3.4% looks back over twelve months. The 2.36% is compensation for the average over the coming ten years, mixed with the premiums above. A breakeven well below the latest 12-month CPI fits bond investors treating the 2026 rate as temporary, but it equally fits a negative risk premium or a high TIPS liquidity premium. The spread does not separate those.
The decomposition also changes how to read the 10-year yield reaching 5.00% on September 15, 2026, the subject of an earlier piece. On Treasury's curves that day, the 5.00% split into a 2.62% real yield and 2.38% of inflation compensation. Measured from December 31, 2025, the real component had risen 0.69 points and the inflation component 0.13.
What it means for your money
The breakeven is a threshold, not an outcome. On October 2, 2026, a saver choosing between a 10-year Treasury at 5.28% and a 10-year TIPS at a 2.92% real yield was choosing a side of 2.36%. If CPI-U averages more than that over the decade, the TIPS ends ahead; if less, the ordinary note does. Nobody knows which in advance.
Prices compounding at a constant 2.36% a year for ten years rise by 1.023610 − 1 = 26.3%. At a constant 3.4%, the August 2026 12-month rate, they rise by 1.03410 − 1 = 39.7%. Both are arithmetic on hypothetical constant rates, not a projection of either.
The more practical lesson is about real returns. The rise in Treasury yields in 2026 was mostly a rise in the real yield: the return above inflation compensation went from 1.93% to 2.92% at ten years. For anyone holding cash or bonds, that is the number that measures how much purchasing power the interest adds, and a separate piece walks through the same arithmetic for savings accounts.
Sources
- Daily Treasury Par Yield Curve Rates, 2026 (CSV)U.S. Department of the Treasury · Oct 4, 2026 · Primary source
- Daily Treasury Par Real Yield Curve Rates, 2026 (CSV)U.S. Department of the Treasury · Oct 4, 2026 · Primary source
- Daily Treasury Par Yield Curve Rates, 2025 (CSV)U.S. Department of the Treasury · Oct 4, 2026 · Primary source
- Daily Treasury Par Real Yield Curve Rates, 2025 (CSV)U.S. Department of the Treasury · Oct 4, 2026 · Primary source
- Interest Rate Statistics (descriptions of the par yield and par real yield curves)U.S. Department of the Treasury · Oct 4, 2026 · Primary source
- 10-Year Breakeven Inflation Rate (T10YIE), observation of October 2, 2026Federal Reserve Bank of St. Louis (FRED), from U.S. Treasury data · Oct 4, 2026 · Primary source
- 5-Year Breakeven Inflation Rate (T5YIE), observation of October 2, 2026Federal Reserve Bank of St. Louis (FRED), from U.S. Treasury data · Oct 4, 2026 · Primary source
- 5-Year, 5-Year Forward Inflation Expectation Rate (T5YIFR), observation of October 2, 2026Federal Reserve Bank of St. Louis (FRED), from U.S. Treasury data · Oct 4, 2026 · Primary source
- Kim, Walsh and Wei, “Tips from TIPS: Update and Discussions”, FEDS Notes, May 21, 2019Board of Governors of the Federal Reserve System · Oct 4, 2026 · Primary source
- 31 CFR 356.2 — Definitions (Consumer Price Index, index ratio, inflation-adjusted principal)Department of the Treasury, Bureau of the Fiscal Service, via eCFR · Oct 4, 2026 · Primary source
- 31 CFR 356.5 — What types of securities does the Treasury auction?Department of the Treasury, Bureau of the Fiscal Service, via eCFR · Oct 4, 2026 · Primary source
- 31 CFR 356.30 — When does the Treasury pay principal and interest on securities?Department of the Treasury, Bureau of the Fiscal Service, via eCFR · Oct 4, 2026 · Primary source
- Appendix B to 31 CFR Part 356 — Formulas and Tables (inflation-protected securities)Department of the Treasury, Bureau of the Fiscal Service, via eCFR · Oct 4, 2026 · Primary source
- Consumer Price Index Summary — August 2026U.S. Bureau of Labor Statistics · Sep 11, 2026 · Primary source
- 10-Year Treasury Constant Maturity Rate (DGS10), observation of September 15, 2026U.S. Department of the Treasury via FRED · Sep 15, 2026 · Primary source
- Schedule of Releases for the Consumer Price Index (2026)U.S. Bureau of Labor Statistics · Oct 4, 2026 · Primary source
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