I bond rates · May 2003 – October 2003

I Bond Rate for May 2003 – October 2003

Announced May 2003 1 by the Treasury: a fixed rate of 1.10%, a semiannual inflation rate of 1.77%, and the 4.66% composite those two produce.

A bond bought in this period earned 4.66% for its first six months and keeps its 1.10% fixed rate for life. With the current inflation rate of 1.67% it earns 4.46% in May 2026 – October 2026.

The May 2003 – October 2003 composite, worked

Treasury's formula: fixed rate + (2 × semiannual inflation rate) + (fixed rate × semiannual inflation rate), rounded to four decimals.

fixed rate                       0.0110   (1.10%)
semiannual inflation rate        0.0177   (1.77%)
0.0110 + (2 × 0.0177) + (0.0110 × 0.0177)
= 0.0110 + 0.0354 + 0.0001947
= 0.0465947
rounded: 0.0466
composite rate: 4.66%   (Treasury publishes 4.66%)

What this cohort has earned since

Its fixed rate never changes; each later period applies that period's inflation rate to it. Rates take effect on the bond's own six-month anniversaries, not on the announcement date.

Period	Inflation rate	This cohort's fixed	Composite
May 2026 – October 2026	1.67%	1.10%	4.46%
November 2025 – April 2026	1.56%	1.10%	4.24%
May 2025 – October 2025	1.43%	1.10%	3.98%
November 2024 – April 2025	0.95%	1.10%	3.01%
May 2024 – October 2024	1.48%	1.10%	4.08%
November 2023 – April 2024	1.97%	1.10%	5.06%
May 2023 – October 2023	1.69%	1.10%	4.50%
November 2022 – April 2023	3.24%	1.10%	7.62%
May 2022 – October 2022	4.81%	1.10%	10.77%
November 2021 – April 2022	3.56%	1.10%	8.26%
May 2021 – October 2021	1.77%	1.10%	4.66%
November 2020 – April 2021	0.84%	1.10%	2.79%
May 2020 – October 2020	0.53%	1.10%	2.17%
November 2019 – April 2020	1.01%	1.10%	3.13%
May 2019 – October 2019	0.70%	1.10%	2.51%
November 2018 – April 2019	1.16%	1.10%	3.43%
May 2018 – October 2018	1.11%	1.10%	3.33%
November 2017 – April 2018	1.24%	1.10%	3.59%
May 2017 – October 2017	0.98%	1.10%	3.07%
November 2016 – April 2017	1.38%	1.10%	3.88%
May 2016 – October 2016	0.08%	1.10%	1.26%
November 2015 – April 2016	0.77%	1.10%	2.65%
May 2015 – October 2015	-0.80%	1.10%	0.00% (floored)
November 2014 – April 2015	0.74%	1.10%	2.59%
May 2014 – October 2014	0.92%	1.10%	2.95%
November 2013 – April 2014	0.59%	1.10%	2.29%
May 2013 – October 2013	0.59%	1.10%	2.29%
November 2012 – April 2013	0.88%	1.10%	2.87%
May 2012 – October 2012	1.10%	1.10%	3.31%
November 2011 – April 2012	1.53%	1.10%	4.18%
May 2011 – October 2011	2.30%	1.10%	5.73%
November 2010 – April 2011	0.37%	1.10%	1.84%
May 2010 – October 2010	0.77%	1.10%	2.65%
November 2009 – April 2010	1.53%	1.10%	4.18%
May 2009 – October 2009	-2.78%	1.10%	0.00% (floored)
November 2008 – April 2009	2.46%	1.10%	6.05%
May 2008 – October 2008	2.42%	1.10%	5.97%
November 2007 – April 2008	1.53%	1.10%	4.18%
May 2007 – October 2007	1.21%	1.10%	3.53%
November 2006 – April 2007	1.55%	1.10%	4.22%
May 2006 – October 2006	0.50%	1.10%	2.11%
November 2005 – April 2006	2.85%	1.10%	6.83%
May 2005 – October 2005	1.79%	1.10%	4.70%
November 2004 – April 2005	1.33%	1.10%	3.77%
May 2004 – October 2004	1.19%	1.10%	3.49%
November 2003 – April 2004	0.54%	1.10%	2.19%
May 2003 – October 2003	1.77%	1.10%	4.66%

Source: TreasuryDirect — I bonds interest rates (fixed-rate and inflation-rate history). Composites are recomputed with Treasury's formula and checked against Treasury's published figures before publication. Bonds cashed before five years forfeit the last three months of interest.

Informational only, not financial or tax advice.

Last reviewed: May 2026 announcement · snapshot built 2026-10-26 from treasurydirect.gov.

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