BondValue

I bond inflation-rate history

Every 6 months the Treasury sets a semiannual inflation rate for I bonds from the change in CPI-U. It has ranged from a low of -2.78% (May 2009 - October 2009, deflation) to a high of 4.81% (May 2022 - October 2022) — the period behind the record 9.62% composite. The current semiannual rate is 1.67% (May 2026 - October 2026), which annualizes to 3.34%. The inflation rate, unlike the fixed rate, applies to every bond for the matching 6-month window.

Source: TreasuryDirect. Data as of May 2026.

Semiannual inflation rate by period

Period setSemiannual inflationAnnualized
May 2026 - October 2026 1.67% 3.34%
November 2025 - April 2026 1.56% 3.12%
May 2025 - October 2025 1.43% 2.86%
November 2024 - April 2025 0.95% 1.90%
May 2024 - October 2024 1.48% 2.96%
November 2023 - April 2024 1.97% 3.94%
May 2023 - October 2023 1.69% 3.38%
November 2022 - April 2023 3.24% 6.48%
May 2022 - October 2022 4.81% 9.62%
November 2021 - April 2022 3.56% 7.12%
May 2021 - October 2021 1.77% 3.54%
November 2020 - April 2021 0.84% 1.68%
May 2020 - October 2020 0.53% 1.06%
November 2019 - April 2020 1.01% 2.02%
May 2019 - October 2019 0.70% 1.40%
November 2018 - April 2019 1.16% 2.32%
May 2018 - October 2018 1.11% 2.22%
November 2017 - April 2018 1.24% 2.48%
May 2017 - October 2017 0.98% 1.96%
November 2016 - April 2017 1.38% 2.76%
May 2016 - October 2016 0.08% 0.16%
November 2015 - April 2016 0.77% 1.54%
May 2015 - October 2015 -0.80% -1.60%
November 2014 - April 2015 0.74% 1.48%
May 2014 - October 2014 0.92% 1.84%
November 2013 - April 2014 0.59% 1.18%
May 2013 - October 2013 0.59% 1.18%
November 2012 - April 2013 0.88% 1.76%
May 2012 - October 2012 1.10% 2.20%
November 2011 - April 2012 1.53% 3.06%
May 2011 - October 2011 2.30% 4.60%
November 2010 - April 2011 0.37% 0.74%
May 2010 - October 2010 0.77% 1.54%
November 2009 - April 2010 1.53% 3.06%
May 2009 - October 2009 -2.78% -5.56%
November 2008 - April 2009 2.46% 4.92%
May 2008 - October 2008 2.42% 4.84%
November 2007 - April 2008 1.53% 3.06%
May 2007 - October 2007 1.21% 2.42%
November 2006 - April 2007 1.55% 3.10%
May 2006 - October 2006 0.50% 1.00%
November 2005 - April 2006 2.85% 5.70%
May 2005 - October 2005 1.79% 3.58%
November 2004 - April 2005 1.33% 2.66%
May 2004 - October 2004 1.19% 2.38%
November 2003 - April 2004 0.54% 1.08%
May 2003 - October 2003 1.77% 3.54%
November 2002 - April 2003 1.23% 2.46%
May 2002 - October 2002 0.28% 0.56%
November 2001 - April 2002 1.19% 2.38%
May 2001 - October 2001 1.44% 2.88%
November 2000 - April 2001 1.52% 3.04%
May 2000 - October 2000 1.91% 3.82%
November 1999 - April 2000 1.76% 3.52%
May 1999 - October 1999 0.86% 1.72%
November 1998 - April 1999 0.86% 1.72%
September 1998 - October 1998 0.62% 1.24%

Source: TreasuryDirect Series I rate chart. Data as of May 2026.

Related histories

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