United States · Savings bonds
I bond interest rate history.
Every fixed rate, six-month inflation rate and combined rate announced since September 1998, with a calculator.
The I bond combined rate for bonds issued May 1, 2026 through October 31, 2026 is 4.26%: a 0.90% fixed rate plus a 1.67% six-month inflation rate. TreasuryDirect announces new rates every May 1 and November 1, so the next change is November 1, 2026.
Combined rate calculator
Combined annual rate
All 57 announcements, newest first
| Date set | Fixed rate | Six-month inflation | Combined rate |
|---|---|---|---|
| 2026-05-01 | 0.90% | 1.67% | 4.26% |
| 2025-11-01 | 0.90% | 1.56% | 4.03% |
| 2025-05-01 | 1.10% | 1.43% | 3.98% |
| 2024-11-01 | 1.20% | 0.95% | 3.11% |
| 2024-05-01 | 1.30% | 1.48% | 4.28% |
| 2023-11-01 | 1.30% | 1.97% | 5.27% |
| 2023-05-01 | 0.90% | 1.69% | 4.30% |
| 2022-11-01 | 0.40% | 3.24% | 6.89% |
| 2022-05-01 | 0.00% | 4.81% | 9.62% |
| 2021-11-01 | 0.00% | 3.56% | 7.12% |
| 2021-05-01 | 0.00% | 1.77% | 3.54% |
| 2020-11-01 | 0.00% | 0.84% | 1.68% |
| 2020-05-01 | 0.00% | 0.53% | 1.06% |
| 2019-11-01 | 0.20% | 1.01% | 2.22% |
| 2019-05-01 | 0.50% | 0.70% | 1.90% |
| 2018-11-01 | 0.50% | 1.16% | 2.83% |
| 2018-05-01 | 0.30% | 1.11% | 2.52% |
| 2017-11-01 | 0.10% | 1.24% | 2.58% |
| 2017-05-01 | 0.00% | 0.98% | 1.96% |
| 2016-11-01 | 0.00% | 1.38% | 2.76% |
| 2016-05-01 | 0.10% | 0.08% | 0.26% |
| 2015-11-01 | 0.10% | 0.77% | 1.64% |
| 2015-05-01 | 0.00% | -0.80% | see note (formula is negative) |
| 2014-11-01 | 0.00% | 0.74% | 1.48% |
| 2014-05-01 | 0.10% | 0.92% | 1.94% |
| 2013-11-01 | 0.20% | 0.59% | 1.38% |
| 2013-05-01 | 0.00% | 0.59% | 1.18% |
| 2012-11-01 | 0.00% | 0.88% | 1.76% |
| 2012-05-01 | 0.00% | 1.10% | 2.20% |
| 2011-11-01 | 0.00% | 1.53% | 3.06% |
| 2011-05-01 | 0.00% | 2.30% | 4.60% |
| 2010-11-01 | 0.00% | 0.37% | 0.74% |
| 2010-05-01 | 0.20% | 0.77% | 1.74% |
| 2009-11-01 | 0.30% | 1.53% | 3.36% |
| 2009-05-01 | 0.10% | -2.78% | see note (formula is negative) |
| 2008-11-01 | 0.70% | 2.46% | 5.64% |
| 2008-05-01 | 0.00% | 2.42% | 4.84% |
| 2007-11-01 | 1.20% | 1.53% | 4.28% |
| 2007-05-01 | 1.30% | 1.21% | 3.74% |
| 2006-11-01 | 1.40% | 1.55% | 4.52% |
| 2006-05-01 | 1.40% | 0.50% | 2.41% |
| 2005-11-01 | 1.00% | 2.85% | 6.73% |
| 2005-05-01 | 1.20% | 1.79% | 4.80% |
| 2004-11-01 | 1.00% | 1.33% | 3.67% |
| 2004-05-01 | 1.00% | 1.19% | 3.39% |
| 2003-11-01 | 1.10% | 0.54% | 2.19% |
| 2003-05-01 | 1.10% | 1.77% | 4.66% |
| 2002-11-01 | 1.60% | 1.23% | 4.08% |
| 2002-05-01 | 2.00% | 0.28% | 2.57% |
| 2001-11-01 | 2.00% | 1.19% | 4.40% |
| 2001-05-01 | 3.00% | 1.44% | 5.92% |
| 2000-11-01 | 3.40% | 1.52% | 6.49% |
| 2000-05-01 | 3.60% | 1.91% | 7.49% |
| 1999-11-01 | 3.40% | 1.76% | 6.98% |
| 1999-05-01 | 3.30% | 0.86% | 5.05% |
| 1998-11-01 | 3.30% | 0.86% | 5.05% |
| 1998-09-01 | 3.40% | 0.62% | 4.66% |
The combined rate column is computed with TreasuryDirect’s published formula for a bond issued in that window at the inflation rate announced the same day. It matches all 57 combined rates in TreasuryDirect’s own current-rate table when each window’s fixed rate is paired with the May 2026 inflation rate. For May 1, 2009 and May 1, 2015 the formula gives a negative number; TreasuryDirect says the rate stops at zero, but the page used here does not publish a figure for those two cases, so none is shown.
Worked example
Bonds issued May 2026: fixed 0.90%, six-month inflation 1.67%. Combined = 0.0090 + (2 × 0.0167) + (0.0090 × 0.0167) = 0.0425503, which rounds to 4.26%. A bond bought in May 2023 also carries a 0.90% fixed rate for life, so today it earns the same 4.26%. To check any other bond, choose the date its fixed rate was set in the calculator above.
Plain-language explainer
An I bond earns a combined rate made of two parts. The fixed rate is set when you buy and never changes. The inflation rate resets every six months based on the non-seasonally adjusted CPI-U and applies to every I bond ever issued. Interest is added to the bond twice a year and compounds.
Your own bond’s rate changes every six months counted from the month you bought it, not on May 1 and November 1 for everyone; TreasuryDirect’s page has the month-by-month table. The six-month inflation figure is an unannualised number, which is why the formula doubles it.
Cite this page
TNAADO Tools. "I Bond Interest Rate History." https://tools.tnaado.ca/us/i-bond-rate-history.html Data as of 2026-10-01. Source: U.S. Department of the Treasury, TreasuryDirect.
Sources: TreasuryDirect, I bonds interest rates (fixed rate and inflation rate tables, composite formula; downloaded 2026-10-01).
Frequently asked questions
What is the current I bond rate?
4.26% for bonds issued May 1 to October 31, 2026 (0.90% fixed plus 1.67% six-month inflation), per TreasuryDirect.
When does the I bond rate change?
Treasury announces new rates every May 1 and November 1. Your own bond’s rate changes six months after its issue month, then every six months.
What is the fixed rate on I bonds today?
The fixed rate set May 1, 2026 is 0.90%. It applies for the life of any bond issued from May 1 to October 31, 2026.
Can an I bond rate go below zero?
No. TreasuryDirect says deflation can pull the combined rate below the fixed rate, but it stops at zero.
How is the combined rate calculated?
Fixed rate + (2 × six-month inflation rate) + (fixed rate × six-month inflation rate), rounded to four decimal places. The calculator above applies this exactly.
Reference data, not advice
Figures are copied from the primary sources linked above as of October 1, 2026. Always confirm against the source before relying on a number for a filing, contract or loan.