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Series I savings bonds
Since 1998· Asset or instrument
Fact, law or dataA rule, statute, definition or measured number.
I bonds are non-tradable US savings bonds whose rate combines a fixed rate with one reset every six months for inflation.
See it on the Money & Finance map →How it works
Launched in 1998, they are sold only online at TreasuryDirect, from $25 up to $10,000 per person per year. The rate has two parts: a fixed rate set at purchase for the bond's life, and an inflation rate reset each May and November from the CPI. The combined rate cannot fall below zero. You must hold for a year; cashing out before five years forfeits the last three months' interest. Interest is state-tax-free and federally tax-deferred until you redeem, up to 30 years.
Why it matters
They give small savers a simple, government-backed inflation hedge that cannot lose nominal value; in 2022 they briefly paid 9.62%.
Facts, rules and data
Treasury publishes every rate and the formula at TreasuryDirect; rules are in federal regulations (31 CFR Part 359). Buying is only through a TreasuryDirect account, since paper bonds via tax refunds ended in 2024.
Connections (3)
▸Series I savings bonds pay a rate tied to Inflation: rising prices, shrinking purchasing powerFact, law or data
The connection
Every May and November the Treasury resets the inflation part of the I bond rate from the six-month change in the CPI-U, annualized, and adds the bond's fixed rate. Each bond earns the new rate for six months from its own issue anniversary, so its value keeps pace with rising prices.
When and why
Rates are announced each May 1 and November 1 by Treasury's Bureau of the Fiscal Service, using Bureau of Labor Statistics CPI data.
How we know
The formula and every rate since 1998 are published at TreasuryDirect, and redemption values follow them exactly.
Debates and risks
Whether the six-month CPI lag shortchanges holders when inflation turns fast, and whether a near-zero fixed rate makes them worth holding long-term.
▸Series I savings bonds are sold only through TreasuryDirect: buying Treasuries directlyFact, law or data
The connection
I bonds cannot be bought from a bank or broker or resold. Since banks stopped selling paper savings bonds in 2012, and paper I bonds bought with tax refunds ended in 2024, a TreasuryDirect account is the only way in: $25 minimum, $10,000 per person a year, redeemed there too.
When and why
Online at TreasuryDirect.gov since 2002, run by Treasury's Bureau of the Fiscal Service. Trusts and businesses can buy their own $10,000 allotments.
How we know
Federal savings bond regulations (31 CFR Part 359) and Treasury's notices ending paper sales spell out the rules.
Debates and risks
Whether the $10,000 cap should rise, and whether Treasury will modernize the dated site that strained under the 2022 rush.
▸The 2021–23 inflation surge pushed rates to 9.62% on Series I savings bondsFact, law or data
The connection
Because the I bond rate resets from CPI, the inflation surge flowed straight into it: the rate set for May to October 2022 was 9.62% a year, with a 0% fixed part. Savers rushed in, buying nearly $1 billion on a single day in late October 2022. As inflation cooled the rate fell, to 6.89% that November.
When and why
Rate announced in May 2022 by Treasury's Bureau of the Fiscal Service; the buying rush peaked on TreasuryDirect in October 2022.
How we know
TreasuryDirect's published rate history and Treasury sales reports.
Debates and risks
How many buyers kept their I bonds after rates fell; the $10,000 yearly cap kept the boom small relative to the inflation it hedged.