Rates Hub / I-Bonds
I-Bond Composite Rate
The current I-Bond composite rate is 4.26% for bonds bought before the November 1, 2026 reset: a 0.90% fixed rate for the life of the bond plus a 1.67% semiannual inflation rate, set on May 1, 2026. The next reset is November 1, 2026; with 6 of the 6 CPI months published, the inflation component is running at 2.04% semiannual (4.08% annualised).
I-Bond rate history
How has the I-Bond rate moved at each six-month reset?
Over the last 24 rate periods the composite rate peaked at 9.62% for bonds issued from May 1, 2022. The fixed-rate part stays with a bond for its life; the rest resets with inflation.
Next reset: November 1, 2026
The Treasury announces the next I-Bond rate on November 1, 2026. The inflation half of that rate is set mechanically from CPI-U between March 2026 and September 2026; the fixed half is announced on the day and cannot be known in advance.
Through September 2026 CPI (index 336.940 vs 330.213 in March 2026). All six CPI months are published, so the inflation component above is what Treasury will use; only the fixed rate is unknown.Bonds bought before the reset keep the current composite for their first six months.
Download I bond rate history (CSV)
I-Bond value calculator
Estimate what a Series I bond is worth over time at the current rate.
Estimated value: —
How the I-Bond rate works
A Series I savings bond earns a composite rate that combines afixed rate (set for the life of the bond at purchase) and asemiannual inflation rate (reset twice a year based on CPI). The U.S. Treasury publishes new rates on May 1 and November 1. The composite formula is:
composite = fixed + (2 × semiannual inflation) + (fixed × semiannual inflation)
Interest is added monthly and compounds semiannually. You must hold an I-Bond for at least1 year. If you redeem before 5 years, you forfeit the most recent3 months of interest. Figures here are estimates that assume the current rate persists; the actual rate your bond earns resets every six months.