Sources and update policy

We use primary government sources for calculations. This source ledger covers the tax year from 6 April 2026 to 5 April 2027.

Primary sources

• HMRC: Rates and thresholds for employers, 2026 to 2027 — PAYE bands, Class 1 National Insurance and student-loan thresholds.
• GOV.UK: Income Tax rates and allowances — Personal Allowance and taper explanation.
• GOV.UK: Repaying your student loan — repayment guidance and plan information.

Update policy

We review published rates before the start of each new tax year and update this ledger when the calculator logic changes. A rate is not treated as confirmed merely because it appears in a secondary source or on a competitor site.

Corrections

If you spot an issue, email the site operator with the page URL, the result, your inputs and the primary source that supports the correction. We will review the report and correct confirmed errors.