§ Sources
Sourced to HMRC, end-to-end.
Every tax rate, every threshold, every band in our calculators is taken directly from official HMRC and gov.uk publications. Below are the primary references the engine cites.
Verified
§ Primary references
04
Direct taxes: rates and allowances for 2026/27
House of Commons Library
When HMRC publishes corrections or new tax-year rates, the engine's rate file is updated and the change is reflected here within seven days. Calculations carry a verified stamp so you can see how recent the data is.