Savings iBond Calculator
Calculate the current value and returns of your US Treasury iBonds with our free calculator. Get accurate valuations based on official Treasury data, including inflation adjustments and interest earnings for your Series I Savings Bonds investment.
iBond Calculator Tool
Minimum holding period
12 months
Cannot be redeemed before 12 months
Interest accrual
Every 6 months
Interest compounds automatically
Purchase limits
$25 - $10,000/year
Per person per calendar year
Inflation protection
Rate adjusts automatically
Protects against inflation
Investment Amount
Enter your iBond purchase amount
Purchase Date
When did you buy the iBond?
Ready to Calculate Your iBond Value
Enter your investment amount and purchase date to see the current value of your iBonds.
Tip: Your iBond value is calculated using official US Treasury data and includes compound interest.
Frequently asked questions
Get answers to common questions about iBonds, calculations, and how to maximize your savings.
What is a U.S. Series I Savings Bond and how does it work?
A Series I Savings Bond is a government-backed security that protects your savings from inflation by earning a combination of a fixed rate and a variable inflation rate. Your bond earns interest for up to 30 years, and the interest compounds semiannually. The principal is protected by the U.S. government.
How do I find the value of my savings bond?
You can instantly check your bond's value using our calculator—no login required and works for both electronic and paper bonds. Enter your purchase date and amount for instant results.
When can I cash in my iBond? Is there a penalty?
You must hold iBonds for at least 12 months, and if you cash them before 5 years, you'll forfeit the last 3 months of interest. After 5 years, you can redeem anytime with no penalty.
How are iBonds different from EE Bonds?
iBonds protect against inflation with variable rates, while EE Bonds offer predictable growth with a fixed rate and a doubling guarantee after 20 years.
Do I have to pay taxes on savings bond interest?
Yes, you'll pay federal income tax on iBond interest, but it's exempt from state and local taxes. You can choose to pay annually or defer until redemption. If used for qualified education expenses, some or all interest may be tax-free.
What do I need to cash in a paper savings bond at a bank?
You'll need valid photo ID and the physical bond. If your name has changed since purchase, bring official documentation of the name change. Not all banks cash savings bonds, so call ahead.
What happens to a savings bond after 30 years?
After 30 years (final maturity), your bond stops earning interest but retains its full value and can still be redeemed for cash. Bonds never become worthless.