Our data source
All interest rates on TreasuryRateHub come from one official source: the U.S. Department of the Treasury’s Daily Treasury Par Yield Curve Rates. We retrieve them from the Treasury’s public daily interest rate XML feed. We do not use paid data vendors, and we do not show intraday or real-time market prices.
What the rates are
The Treasury publishes a par yield curve each business day. According to the Treasury, the curve is based on closing market bid prices for the most recently auctioned Treasury securities and gives yields for fixed maturities from 1 month to 30 years. A par yield is the coupon rate at which a hypothetical new security of that maturity would be priced at its face value. Rates are annualized percentages on a bond-equivalent basis. Because they are read off a curve at fixed maturities, they are also known as constant maturity rates.
These rates are not auction results. Treasury bill auctions, for example, report a discount rate and an investment rate for the specific bill sold, which can differ from the daily curve.
How we collect and check the data
- Fixed, official source. Our server requests data only from the Treasury’s feed address. Visitors’ browsers never contact the Treasury on our behalf.
- Schedule. The Treasury publishes each business day’s rates late that day, Eastern time. We check for new data several times on publication days and once a day otherwise, so revisions are picked up.
- Validation. Before storing anything, we check that the response is a well-formed Treasury feed, that each entry has a real business-day date that is not in the future, that the key maturities are present, and that every value is a number within a plausible range. Entries that fail are rejected and logged.
- No gaps filled. If a maturity is not published on a date, we store and show nothing for it. We never interpolate, estimate or carry values forward.
- Last good data kept. If a refresh fails or returns unusable data, the previously validated data stays in place and is shown with its original observation date.
- Freshness check. We compare the newest observation with the business day we expect to have, accounting for weekends and bond-market holidays. If more than one expected business day is missing, pages show a notice that the data may be out of date.
How we display the data
- Every rate is shown with its observation date.
- Rates are shown as published, to two decimal places.
- Daily change compares a rate with the previous published observation for the same maturity. Changes are shown in percentage points and in basis points (1 percentage point = 100 basis points), with an arrow and text so the direction does not depend on color.
- 1 week, 1 month and 1 year ago use the most recent observation on or before that date, and the actual date used is shown.
- Month-end and year-end values are the last observation in each period. Averages are simple averages of daily observations, and the current year is labeled as partial.
- Key takeaways on the rates dashboard are generated automatically from the numbers, such as the difference between the 10-year and 2-year yields. They are descriptions of the data, not forecasts or advice.
Historical coverage and known gaps
Our history begins on January 2, 1990, when the Treasury’s daily par yield curve series starts. Not every maturity exists for the whole period. Examples: the 2-month rate begins in 2018 and the 4-month rate in 2022, newer short maturities appear only from their introduction, and the 30-year rate is absent from 2002 to 2006 because the Treasury suspended 30-year bond issuance during that period. These gaps appear as breaks in charts and blank cells in tables and downloads.
Calculators
Our Treasury Bill Calculator uses the bill pricing and yield formulas published by TreasuryDirect, including the special formula for bills longer than half a year, and shows the formula and inputs with every result. The Treasury Spread Calculator subtracts one published yield from another and uses only dates where both exist. Calculators run in your browser and are tested against hand-worked examples. They are educational tools and do not include taxes, fees or your personal circumstances.
We do not offer a savings bond valuation calculator because accurate values depend on series-specific rules and the Treasury’s redemption tables. Our savings bond guide links to the official calculator.
Limitations
- End-of-day rates, not live prices. Market yields during the day can differ.
- Par yields for constant maturities, not the yield on any specific security you might own.
- Publication can be delayed by the Treasury or interrupted by technical problems; the freshness notice tells you when.
- Rounding: figures are shown to two decimals as published; calculations use full precision and are rounded for display.
Independence
TreasuryRateHub is independent. We are not affiliated with, sponsored by or endorsed by the U.S. Department of the Treasury, TreasuryDirect, the Federal Reserve or any government agency. Use of public Treasury data does not imply any endorsement.
Corrections
If you believe a number or explanation on this site is wrong, please tell us through our contact page. Our corrections policy explains how we review and fix errors.