A Series I Savings Bond earns interest for 30 years from its issue date. That span is built as a 20-year original maturity followed by an automatic 10-year extension, and once the 30-year mark hits, the bond reaches final maturity and stops growing in value for good. So the short answer to how long I Bonds earn interest is three decades, no renewals, no extensions beyond that.
The 20-Year Original Maturity and 10-Year Extension
Federal regulations set the lifespan of a Series I Bond at 20 years of original maturity plus a 10-year extended maturity period that begins automatically.1eCFR. 31 CFR 359.5 – What Is the Maturity Period of a Series I Savings Bonds You do not need to do anything when the bond crosses from one phase to the next. It simply keeps earning interest under the same rules.
Inside both phases, the composite rate is recalculated every six months based on the fixed rate locked in at purchase and the current semiannual inflation rate. The fixed rate stays with the bond for its entire life. The inflation component changes each May and November, so the rate on a bond you have held for 15 years will not look like the rate when you bought it, but the bond is still earning on the same schedule.
What Happens at 30 Years
At 30 years from the issue date, the bond reaches final maturity and stops earning interest entirely.1eCFR. 31 CFR 359.5 – What Is the Maturity Period of a Series I Savings Bonds The value freezes. Inflation can run high the following year and the bond will not move. There is no further extension, and the rule applies to every I Bond regardless of denomination or owner.
A bond issued in May 1999, for example, reached its original maturity in May 2019 and will hit final maturity in May 2029. After that, holding the bond is lending the government money at zero percent. For electronic bonds, the issue date is visible in your TreasuryDirect account, which is the simplest way to see where any bond stands against the 30-year clock.
There is a tax consequence to letting a mature bond sit, too. If you have been deferring reporting until redemption, the full accumulated interest hits a 1099-INT in the year the bond matures or is cashed, whichever comes first.2TreasuryDirect. Tax Information for EE and I Bonds
How Interest Accrues Along the Way
I Bonds start earning on the first day of the month you buy them. Interest accrues monthly, but the Treasury does not add it to the bond’s principal every month. Instead, interest is credited every six months in a process called semiannual compounding, which means each half-year’s interest becomes part of the base that earns the next half-year’s interest.3TreasuryDirect. I Bonds Interest Rates
Because accrual is tied to the first of the month, the date within a month does not affect your return. Cashing a bond on the 2nd and cashing it on the 28th yield the same value. If you are planning a redemption, waiting until just after a new month starts captures that month’s interest; redeeming on the last day of the previous month leaves it behind. The compounding cycle runs continuously until the 30-year mark, when it stops.
When You Can Actually Access the Interesth2>
Earning interest and being able to collect it are not the same thing in the first few years. For bonds issued on or after February 1, 2003, you cannot redeem at all during the first 12 months after the issue date.4eCFR. 31 CFR Part 359 – Offering of United States Savings Bonds, Series I – Section 359.6 The money is locked up. One narrow exception: if you live in a federally declared disaster area, the Treasury will waive the 12-month hold and let you cash early by calling TreasuryDirect or submitting a certified FS Form 5512 marked “DISASTER.”5TreasuryDirect. Affected by a Disaster
After the first year but before five years from the issue date, you can redeem, but you forfeit the last three months of interest.6eCFR. 31 CFR Part 359 – Offering of United States Savings Bonds, Series I – Section 359.7 An 18-month-old bond cashed in that window pays 15 months of interest.7TreasuryDirect. I Bonds The redemption value will not drop below what you paid, even with the penalty applied. Once the bond is five years old, the penalty is gone and you receive the full accrued value whenever you redeem. From year five through year 30, every dollar of earned interest is yours to keep.
Finding and Redeeming Bonds That Have Stopped Earning
If you suspect a bond has already reached final maturity, start with the issue date. Electronic bonds show their status in your TreasuryDirect account. For paper bonds, the Savings Bond Calculator on the TreasuryDirect website takes the series, denomination, and issue date and tells you whether the bond is still earning.
Electronic bonds are redeemed through TreasuryDirect, with the proceeds sent to your linked bank account. Paper bonds are mailed in for processing. If the total paper redemption exceeds $1,000, each signer’s signature must be certified by a notary or a Treasury-recognized signature guarantee program.8TreasuryDirect. Special Form of Request for Payment of United States Savings and Retirement Securities – FS Form 1522 For $1,000 or less in paper bonds, a signed form plus a copy of your government-issued ID is enough.
Treasury Hunt, which previously let people search for matured uncashed bonds, was discontinued on September 30, 2025.9TreasuryDirect. Treasury Hunt Under the SECURE Act 2.0, inquiries about unredeemed matured bonds now flow through state unclaimed property programs; the national search point is unclaimed.org. The Treasury shares information on bonds more than three years past final maturity with state governments to help reunite owners with their money.10TreasuryDirect. 2024 Report to Congress Under the SECURE 2.0 Act of 2022 Savings bonds themselves never technically expire, and there is no deadline to redeem them, but after 30 years they are no longer earning anything.1eCFR. 31 CFR 359.5 – What Is the Maturity Period of a Series I Savings Bonds
Interest After the Owner Dies
An I Bond does not stop earning interest when its owner dies. It keeps growing until it either reaches 30-year final maturity or is cashed by the surviving co-owner, named beneficiary, or estate, whichever comes first.11TreasuryDirect. Inheriting Savings Bonds as a Named Co-Owner or Beneficiary A named survivor can hold a still-earning bond and collect the full accumulated interest later.
Tax treatment then depends on how the original owner handled reporting. If interest was being deferred, the person who inherits the bond generally owes federal income tax on all the accumulated interest when the bond is cashed or matures. On bonds that have been earning for decades, that can be a significant liability, so beneficiaries should check each bond’s issue date against the 30-year clock before deciding when to redeem.