I Bonds in 2026: How the Rate Works, the November 1 Reset and When to Buy
I bonds bought through October 31, 2026 earn 4.26% for their first six months and keep a 0.90% fixed rate for life. On November 1, Treasury resets both numbers. Here’s how the rate is built, what the reset depends on, and who should buy before it or after it.
Current rate: 4.26% for I bonds issued May 1 to October 31, 2026: a 0.90% fixed rate plus a 1.67% six-month inflation rate (3.34% a year). New rates take effect November 1. Buying in October locks the 0.90% fixed rate for 30 years plus six months at 4.26%. TreasuryDirect dates a purchase on the next business day and October 31 is a Saturday, so finish by Thursday, October 29. Whether October or November is better depends mostly on November’s fixed rate, which nobody knows until Treasury announces it.
Current I Bond Rate and Recent History
Treasury announces two numbers every May 1 and November 1: a fixed rate that new bonds keep for life, and an inflation rate that every I bond picks up for six months. Here are the last nine announcements.
| Issue window | Fixed rate | Six-month inflation rate | Composite (new bonds) |
|---|---|---|---|
| May–Oct 2026 | 0.90% | 1.67% | 4.26% |
| Nov 2025–Apr 2026 | 0.90% | 1.56% | 4.03% |
| May–Oct 2025 | 1.10% | 1.43% | 3.98% |
| Nov 2024–Apr 2025 | 1.20% | 0.95% | 3.11% |
| May–Oct 2024 | 1.30% | 1.48% | 4.28% |
| Nov 2023–Apr 2024 | 1.30% | 1.97% | 5.27% |
| May–Oct 2023 | 0.90% | 1.69% | 4.30% |
| Nov 2022–Apr 2023 | 0.40% | 3.24% | 6.89% |
| May–Oct 2022 | 0.00% | 4.81% | 9.62% |
Source: TreasuryDirect rate tables. The composite is an annual rate, paid for six months at a time.
The 9.62% of 2022 came with a 0.00% fixed rate, so those bonds now earn only the inflation rate: 3.34% a year for their current six months. A bond bought in May 2024 kept its 1.30% fixed rate and earns 4.66% over the same stretch. The fixed rate is what separates a good I bond from an ordinary one.
How I Bond Interest Rates Work
- Fixed rate: set when you buy and never changes for the bond’s 30-year life. In recent years it has ranged from 0.00% (2020 to 2022) to 1.30% (November 2023 to October 2024); it’s 0.90% now.
- Inflation rate: the change in the Consumer Price Index for All Urban Consumers (CPI-U, not seasonally adjusted) over six months: September to March for the May 1 rate, March to September for the November 1 rate.
- Composite rate: fixed rate + 2 × six-month inflation rate + fixed rate × six-month inflation rate. For today’s bonds: 0.90% + 2 × 1.67% + (0.90% × 1.67%) = 4.2550%, which Treasury rounds to 4.26%. It can’t go below zero, even with deflation.
Your bond’s rate changes every six months from its issue month, not on May 1 and November 1. A bond issued in October 2026 earns 4.26% (annualized) from October through March, then 0.90% plus November’s inflation rate from April through September 2027, and so on. Interest is added monthly and compounds every six months. TreasuryDirect dates every bond to the first day of its issue month, so a bond bought on October 29 earns interest for all of October.
The November 1, 2026 Reset: What We Know So Far
November’s inflation rate will be the change in CPI-U from March 2026 to September 2026. March’s index was 330.213. Through August 2026, the latest month released, the index is 334.980, up 1.44% since March. September’s number comes out October 14.
- If September’s index is flat with August, the six-month rate would be 1.44% (2.88% a year), down from today’s 1.67%.
- To match today’s rate, the index has to rise about 0.22% from August to September.
- In each of the last five years, it rose between 0.16% and 0.27% from August to September. Repeating that range would give a six-month rate of about 1.61% to 1.72%, or 3.22% to 3.44% a year.
The fixed rate is the bigger unknown. Treasury doesn’t publish a formula for it; it has held at 0.90% for the last two announcements, down from 1.30% in 2024. We’ll update this page when Treasury posts the new rates, which take effect November 1 (a Sunday this year, so the announcement may come on the next business day).
Buy in October or wait for November?
| Buy by Oct 29 | Buy in November | |
|---|---|---|
| Fixed rate for 30 years | 0.90% (known) | Unknown until the announcement |
| First six months | 4.26% a year | New fixed rate + November’s inflation rate |
| Next six months | 0.90% + November’s inflation rate | New fixed rate + May 2027’s inflation rate |
| Counts against | Your 2026 limit ($10,000) | Your 2026 limit ($10,000) |
The inflation part matters less than it looks. If September comes in flat and the fixed rate stays at 0.90%, a November bond would start at 3.79%. On $10,000, the October bond’s first six months earn about $213 and the November bond’s about $190: a difference of about $23.50, once. The fixed rate works differently: each 0.10 point of fixed rate is worth about $10 a year on $10,000 for as long as you hold the bond, up to 30 years.
So if you’ll hold for a year or two, buying in October captures six months at 4.26%. If you’re buying for the long haul, the fixed rate decides it, and splitting the purchase between October and November hedges a surprise either way. Both purchases use the same 2026 limit; if you’ve already bought $10,000 this year, your next chance is January 2027.
Key Rules and Limits
- Purchase limit: $10,000 per person per calendar year, electronic only, through TreasuryDirect. The option to buy an extra $5,000 in paper I bonds with a federal tax refund ended January 1, 2025.
- Separate limits: a child’s account managed by a parent and an entity account (such as a trust or business) each have their own $10,000 limit.
- Gifts: count toward the recipient’s limit in the year they’re delivered, not yours.
- Minimum: $25, then any amount to the penny.
- Holding period: you can’t cash an I bond in its first 12 months. Before five years, you give up the last three months of interest; after five years, there’s no penalty.
- Life: interest stops after 30 years.
- Taxes: interest is subject to federal income tax but exempt from state and local income tax. You can defer the federal tax until you cash the bond or it matures, or report it yearly. Interest used for qualified higher-education costs can be tax-free if the bond is in the name of an owner who was at least 24 when it was issued and income is under the IRS limit (Form 8815).
I Bonds vs Savings, CDs and T-Bills in a Rising-Rate Year
The Fed raised its target range to 3.75%–4.00% on September 16, 2026, and short-term rates moved with it. Here’s how I bonds compare with other safe places for cash in late September 2026.
| Option | Rate now | State income tax | Rate locked for | Access |
|---|---|---|---|---|
| I bond | 4.26% (first six months) | Exempt | Six months; 0.90% above inflation for life | After 12 months; 3-month interest penalty before 5 years |
| Treasury bill | 4.08% (3-month) to 4.27% (1-year)* | Exempt | Its term (4 weeks to 1 year) | At maturity, or sold through a broker |
| High-yield savings | Competitive online accounts pay near bill yields; the national average is 0.37% | Taxed | Nothing; the bank can change it any day | Any time |
| 12-month CD | National average 1.73%; competitive banks pay far more | Taxed | 12 months | Early-withdrawal penalty |
*Secondary-market rates on September 24, 2026 (Federal Reserve H.15, discount basis). National averages: FDIC, September 21, 2026.
- What’s guaranteed: a Treasury bill locks its yield for its term; an I bond locks only 0.90% above inflation. While rates are rising, short bills reinvest at the new level each time they mature.
- Taxes: I bonds and bills both skip state income tax, and I bonds also let you defer federal tax. Bank interest is taxed by your state every year. The after-tax math by state is in T-Bills vs Savings vs CDs vs Money Market Funds; the Cash Yield Showdown puts an I bond next to the others with your numbers.
- Access: the 12-month lock rules I bonds out for money you might need this year. Keep that in savings or a T-bill ladder.
What I bonds add is inflation protection: if prices jump, the next six-month rate jumps with them, while a bill or CD rate doesn’t. For what cash really earns after tax and inflation, see Real Interest Rates; for what the Fed’s move changes, see The Fed Just Raised Rates.
When I Bonds Make Sense — and When They Don’t
I bonds work well when:
- You have savings you won’t need for at least a year and want part of it protected against inflation, with no market risk
- You live in a high-tax state, where the state exemption is worth more
- You’re in a high federal bracket and will hold for years, so deferring the federal tax helps
- You’re saving for college in your own name and expect to qualify for the education exclusion
They’re not ideal when:
- You might need the money within 12 months (see where to keep an emergency fund)
- You want a known rate for a set term: a T-bill or CD gives you that, while an I bond’s rate resets every six months
- You’re investing for decades: stocks have beaten inflation by far more over long periods, with more risk
- You carry high-interest debt: paying off a 20%+ credit card beats any savings rate
Buy at TreasuryDirect.gov; brokers and banks don’t sell I bonds. TreasuryDirect dates a purchase on the next business day, and the issue date is the first day of that month. October 31, 2026 is a Saturday, so a purchase submitted on Friday, October 30 would be dated Monday, November 2 and get the new rate. Submit by Thursday, October 29, and earlier if your account is new or may need identity verification. TreasuryDirect posts the exact cutoff on its home page near the end of the month.