Series I savings bonds
A Series I savings bond is a US government bond whose return tracks inflation. It earns a composite rate made of a fixed rate (set for the life of the bond) and a semiannual inflation rate (reset every 6 months). The current composite rate is 4.26% (May 2026 - October 2026). You can buy $25–$10,000 per person per year via TreasuryDirect, must hold at least 12 months, and lose 3 months of interest if you cash before 5 years. I bonds are exempt from state and local tax.
Source: TreasuryDirect. Data as of May 2026.
Series I bond key facts (May 2026)
| Feature | Detail |
|---|---|
| Current composite rate | 4.26% (May 2026 - October 2026) |
| Current fixed rate | 0.90% |
| Current semiannual inflation rate | 1.67% |
| Annual purchase limit (electronic) | $10,000 per person, per calendar year |
| Minimum purchase | $25 (electronic, via TreasuryDirect) |
| Earns interest for | 30 years |
| Earliest you can cash | After 12 months |
| Early-redemption penalty | Last 3 months of interest if cashed before 5 years |
| Federal tax | Yes (deferrable until redemption/maturity) |
| State & local tax | Exempt |
Source: TreasuryDirect. Data as of May 2026.
Recent I bond rates
| Issue period | Fixed | Inflation | Composite |
|---|---|---|---|
| May 2026 - October 2026 | 0.90% | 1.67% | 4.26% |
| November 2025 - April 2026 | 0.90% | 1.56% | 4.03% |
| May 2025 - October 2025 | 1.10% | 1.43% | 3.98% |
| November 2024 - April 2025 | 1.20% | 0.95% | 3.11% |
| May 2024 - October 2024 | 1.30% | 1.48% | 4.28% |
| November 2023 - April 2024 | 1.30% | 1.97% | 5.27% |
Source: TreasuryDirect Series I rate chart. Data as of May 2026.
Learn more about I bonds
- I bonds explained — the full beginner’s guide.
- How I bond interest accrues — monthly accrual, semiannual compounding.
- The 3-month early-redemption penalty.
- I bond purchase limits.
- I bond taxes (federal-only, education exclusion).
- I bond vs EE bond.
Tools
- I bond value calculator — what your bond is worth now.
- Composite-rate calculator — the official formula.
Frequently asked questions
What is the current I bond rate?
The current Series I bond composite rate is 4.26% for bonds issued May 2026 - October 2026. That combines a 0.90% fixed rate with a 1.67% semiannual inflation rate. Rates reset every May 1 and November 1.
How much can I buy in I bonds per year?
You can buy up to $10,000 in electronic I bonds per Social Security Number per calendar year through TreasuryDirect. A separate paper I bond allowance via tax refunds was discontinued for refunds; check TreasuryDirect for the latest.
Are I bonds a good investment?
I bonds are a low-risk, inflation-protected savings vehicle backed by the U.S. government. They are best for money you can leave alone for at least a year (ideally five, to avoid the penalty). They are not a substitute for a diversified portfolio. This is not investment advice.
When does the I bond rate change?
The Treasury announces new I bond rates on May 1 and November 1 each year. Your specific bond's rate changes every 6 months from its own issue month, rolling onto the newest inflation rate while keeping its original fixed rate.
Not investment or tax advice. BondValue is an independent reference, not affiliated with the U.S. Treasury or TreasuryDirect. Savings bond rates reset every 6 months (on May 1 and November 1), and any value shown here is an estimate. Verify current rates and the exact penny value of your bonds at TreasuryDirect’s official Savings Bond Calculator. Consult a qualified professional before making financial decisions.
Last updated: 2026-06-21