About & methodology

Every number on this site traces to a U.S. Treasury source. Here is exactly how.

What this site does

Savings Bond Check answers two questions well: what is a given US savings bond worth today, and is it still earning interest? It publishes the U.S. Treasury's official redemption values - the value file behind TreasuryDirect's own calculator - as browsable tables for every series, issue year, issue month, and denomination, plus final-maturity rules, current I bond rates, taxes, cashing, and inheritance paths for Series E, EE, I, and HH bonds and Savings Notes.

Who runs it

Savings Bond Check is an independent reference site. It is not affiliated with the U.S. Treasury, TreasuryDirect, the Bureau of the Fiscal Service or any bank, and it does not sell, buy or broker bonds. It exists because the official tools answer one bond at a time behind a login or a download, while most people who find old paper bonds have a stack of them and want plain answers: what each one is worth, whether it still earns, and how to cash or inherit it. The site is free to use and supported by advertising; advertisers have no say in what it publishes. Questions and corrections go to contact@savingsbondcheck.com and are answered by the people who maintain it.

What you can do here

• Savings bond calculator: value any bond, keep an inventory of all of yours in your browser, print the total.
• Value tables for every series, issue year, month and denomination, with the date each bond stops earning.
• I bond rates, current and historical.
• Guides to cashing, taxes, inherited bonds and lost or unclaimed bonds.

What it deliberately does not do

• No invented numbers. Every dollar value is Treasury's published per-$25 redemption value, scaled exactly (face ÷ $25 is a whole number for every denomination). You can cross-check any figure on the official TreasuryDirect Savings Bond Calculator - the two always agree, because they read the same file.
• No investment, tax, or legal advice. Pages describe Treasury's official processes and link to the official source for every claim.
• No predictions - future rates and values appear here only after Treasury publishes them.

Data sources

• Redemption values: the U.S. Treasury Fiscal Data API, Savings Bonds Value Files dataset (endpoint v2/accounting/od/sb_value) - the official redemption value per $25 of face value for every Series E, EE, and I bond and Savings Note, at every redemption month since 1992 (35,936 rows this build, published through November 2026). For bonds under 5 years old the published values already reflect the 3-month early-redemption penalty.
• I bond rates: I Bonds Interest Rates dataset (endpoint v1/accounting/od/i_bonds_interest_rates) - the combined rate for every issue-month cohort in every semiannual rate period since September 1998 (9,690 rows this build). Cross-checked at build time against the announced rate on treasurydirect.gov; the build fails if they disagree.
• Matured/outstanding totals: Monthly Statement of the Public Debt, Table III (endpoint v1/debt/mspd/mspd_table_3) - matured unredeemed savings securities, monthly since 2001, and outstanding amounts by series.
• Bond counts by series: Savings Bonds: Issues, Redemptions, and Maturities by Series (endpoint v1/accounting/od/savings_bonds_report) - monthly counts of bonds issued, redeemed, outstanding, and matured-unredeemed.
• Rules and procedures (maturity periods, series timelines, cashing, inheritance, tax treatment): the relevant TreasuryDirect pages, linked inline wherever a claim is made.

Methodology & integrity checks

Every build re-fetches all four datasets and refuses to publish if any check fails - the previously published site stays live instead. The checks: the I bond composite formula (composite = fixed + 2 × inflation + fixed × inflation, floored at zero) is verified against every row of the rates dataset; the value file must cover the build month, contain all four series with their known issue-year spans, and pass range checks; I bond cohort values must never decrease month over month; matured Series E values must be frozen; and EE bonds issued May 2005 or later must show their guaranteed doubling by 20 years. Per-bond "current rate" figures account for each bond's own six-month reset schedule. Maturity dates are computed from the statutory terms: 30 years for EE and I bonds, 20 for HH, and 30 or 40 years for Series E depending on issue date.

Update cadence

Redemption values and rates change on Treasury's announcement dates, May 1 and November 1; MSPD figures and bond counts update monthly. The site is rebuilt from the live APIs at least monthly (and around each announcement), and every page footer shows its data-refresh date. All underlying data is US-government public domain; this site's tables are free to cite with a link.

Contact

contact@savingsbondcheck.com - corrections are welcome and applied fast.