All values come directly from Federal Reserve via FRED (DPRIME). We do not modify, smooth, or interpolate published values.
The interest rate banks charge their most creditworthy customers. Base rate for adjustable-rate mortgages, credit cards, and HELOCs. Moves with Fed policy, typically Fed Funds + 3.00 percentage points.
Daily — we refresh every hour during US market hours; upstream publishes on business days.
We gate dateModified updates to actual value changes (threshold: 0.01% absolute or 0.5% relative) to prevent freshness spoofing. If the upstream value hasn't moved, we don't claim we updated the page.
Full historical series is available as CSV with primary-source attribution:
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No corrections issued on this series.
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CalcFi. (2026). Prime Lending Rate. Retrieved from https://calcfi.app/data/interest-rates/prime-rate/revisions. Source: Federal Reserve via FRED (DPRIME).
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