September 2025

The zero curve on each of 21 trading days this month.

3.00%3.50%4.00%4.50%5.00%5.50%Sep 2, 2025Sep 30, 2025Sep 2, 20252Y zero rate3.649%10Y zero rate4.352%30Y zero rate5.151%Sep 3, 20252Y zero rate3.608%10Y zero rate4.285%30Y zero rate5.070%Sep 4, 20252Y zero rate3.579%10Y zero rate4.238%30Y zero rate5.034%Sep 5, 20252Y zero rate3.502%10Y zero rate4.162%30Y zero rate4.958%Sep 8, 20252Y zero rate3.484%10Y zero rate4.120%30Y zero rate4.871%Sep 9, 20252Y zero rate3.527%10Y zero rate4.139%30Y zero rate4.885%Sep 10, 20252Y zero rate3.522%10Y zero rate4.108%30Y zero rate4.864%Sep 11, 20252Y zero rate3.512%10Y zero rate4.083%30Y zero rate4.834%Sep 12, 20252Y zero rate3.537%10Y zero rate4.133%30Y zero rate4.863%Sep 15, 20252Y zero rate3.517%10Y zero rate4.112%30Y zero rate4.848%Sep 16, 20252Y zero rate3.495%10Y zero rate4.102%30Y zero rate4.827%Sep 17, 20252Y zero rate3.514%10Y zero rate4.125%30Y zero rate4.843%Sep 18, 20252Y zero rate3.545%10Y zero rate4.180%30Y zero rate4.916%Sep 19, 20252Y zero rate3.553%10Y zero rate4.206%30Y zero rate4.934%Sep 22, 20252Y zero rate3.577%10Y zero rate4.218%30Y zero rate4.941%Sep 23, 20252Y zero rate3.562%10Y zero rate4.186%30Y zero rate4.908%Sep 24, 20252Y zero rate3.589%10Y zero rate4.221%30Y zero rate4.948%Sep 25, 20252Y zero rate3.645%10Y zero rate4.239%30Y zero rate4.927%Sep 26, 20252Y zero rate3.638%10Y zero rate4.260%30Y zero rate4.939%Sep 29, 20252Y zero rate3.615%10Y zero rate4.215%30Y zero rate4.883%Sep 30, 20252Y zero rate3.591%10Y zero rate4.224%30Y zero rate4.921%
2Y zero rate10Y zero rate30Y zero rate
Zero rate first, last, low and high for each charted tenor across September 2025.
TenorFirstLastChangeLowHigh
2Y3.649%3.591%-5.8 bp3.484%Sep 8, 20253.649%Sep 2, 2025
10Y4.352%4.224%-12.7 bp4.083%Sep 11, 20254.352%Sep 2, 2025
30Y5.151%4.921%-22.9 bp4.827%Sep 16, 20255.151%Sep 2, 2025

Rates are percent; the change column is basis points. A rise in yield is a fall in price, so the colours here describe the rate rather than a bondholder's return.

Every trading day

Zero rate at 2, 10 and 30 years for every fitted trading day in September 2025.
Date2 year10 year30 year
Sep 2, 20253.649%4.352%5.151%
Sep 3, 20253.608%4.285%5.070%
Sep 4, 20253.579%4.238%5.034%
Sep 5, 20253.502%4.162%4.958%
Sep 8, 20253.484%4.120%4.871%
Sep 9, 20253.527%4.139%4.885%
Sep 10, 20253.522%4.108%4.864%
Sep 11, 20253.512%4.083%4.834%
Sep 12, 20253.537%4.133%4.863%
Sep 15, 20253.517%4.112%4.848%
Sep 16, 20253.495%4.102%4.827%
Sep 17, 20253.514%4.125%4.843%
Sep 18, 20253.545%4.180%4.916%
Sep 19, 20253.553%4.206%4.934%
Sep 22, 20253.577%4.218%4.941%
Sep 23, 20253.562%4.186%4.908%
Sep 24, 20253.589%4.221%4.948%
Sep 25, 20253.645%4.239%4.927%
Sep 26, 20253.638%4.260%4.939%
Sep 29, 20253.615%4.215%4.883%
Sep 30, 20253.591%4.224%4.921%

Index levels before September 30, 2026 are back-tested. They were computed after the fact by applying the rules to historical data, which benefits from hindsight in the choice of rules, and an index cannot be invested in directly. Methodology v1.0 takes effect at that rebalance, when levels begin to be struck on the day; the rulebook is identical either way, and the version is published on every row.

A fitted curve is a fit, not a quote. Daily error averages 3.8 basis points across the history and reaches about 20 on the worst days, in December 2008, when the market was genuinely hard to fit one smooth curve to. Every curve page publishes its own fit error rather than burying it.

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Safe Rate™, Safe Rate Indices™ and the Safe Rate US Treasury Index™ are trademarks of Safe Rate, claimed through use in commerce and not registered. Third-party marks are the property of their owners, which are not affiliated with and do not endorse this data.

Curves are fitted from public Treasury data and carry fit error; figures are not a record of trading, and an index cannot be invested in directly. No claim of compliance with the IOSCO Principles for Financial Benchmarks is made or implied. Not investment advice, not an offer, and not a recommendation to buy or sell any security.