About US Bond Value
Radif Partners rebuilds the value of Series EE and I savings bonds from the rules written in 31 CFR parts 351 and 359: the $25 and $12.50 accrual units, rounding to the cent, the three-month penalty and the 30-year stop. Every engine run is checked against the redemption tables the Treasury published from 1999 to 2023. Treasury bill yields come from the auction results on Fiscal Data, and state tax schedules from each revenue department. The site sells no bond, account or advice and asks for no e-mail.
The gap this site fills
Many savings bonds still sit in drawers as paper bonds from a grandparent or a payroll plan, while every new bond is electronic: EE bonds since 2012, I bonds since January 1, 2025. The Treasury's own calculator values paper bonds only, one at a time, and stops at the end of the current rate period. Electronic bonds can be valued only by logging into the account that holds them, which an heir or a tax preparer often cannot do. News articles about I bond rates stay in search results for years after their rate has expired, and Treasury bill pages leave you to guess your state tax rate.
This site does better than the first Google result because its calculator gives the value of EE and I bonds, paper and electronic, month by month and checked against the Treasury's redemption tables, the current rate of each I bond by its issue month, and the yield of each Treasury bill converted into a taxable equivalent with your state's 2026 schedule, where the Treasury's tool handles paper bonds only and other pages ask you to type your state rate by hand.
Who publishes it
The site is published by Radif Partners, a company that builds calculators on public rules. It is not a bank, a broker, a dealer in securities, an investment adviser or a government agency, receives no commission and has no partner to send you to. Pages carry no affiliate link.
Radif Partners
49 rue du Ressort
63000 Clermont-Ferrand, France
contact@usbondvalue.com
What we rely on
The regulations for Series EE and I bonds (31 CFR 351 and 31 CFR 359), the TreasuryDirect rate tables and the Series I rate history, the 291 monthly redemption tables published on Fiscal Data from March 1999 to May 2023, the Fiscal Data auction results for Treasury bills, the CPI-U published by the Bureau of Labor Statistics, IRS Publications 550 and 970, Form 8815, Rev. Proc. 2025-32, and the revenue department of each state and DC.
What the site leaves out
We cannot look up a bond by serial number, tell you whether a paper bond was already cashed, or find lost bonds: only the Treasury can. Rates that are not announced yet are left blank unless you ask for a projection, which is labeled. The method page lists every formula and its limits; the editorial policy explains corrections.
Contact
contact@usbondvalue.com, for corrections and sources. We answer questions about a rule, not about your personal situation.