Tax Calculation Sources
Last reviewed: July 2026 · Updated for the 2026/27 tax year
Primary sources
PayToolkit calculators are built directly from official UK government and HMRC publications, including:
- HMRC Income Tax rates and Personal Allowances
- HMRC National Insurance thresholds and rates
- HMRC dividend tax rates and allowances
- HMRC Capital Gains Tax rates and allowances
- HMRC VAT rates and registration thresholds
- HMRC Corporation Tax rates
- UK Government Stamp Duty Land Tax bands
- DVLA vehicle tax (VED) bands
Official links
You can verify any calculator against the official source at gov.uk/income-tax-rates, gov.uk/national-insurance, and the wider gov.uk business tax section.
How often sources are checked
Rates are checked against official sources at the start of each tax year and after any Budget or in-year policy announcement. See Methodology for the full update process.
Source by area
| Area | Where the rules come from |
|---|---|
| Income Tax rates and allowances | GOV.UK — Income Tax rates and Personal Allowances |
| National Insurance | GOV.UK — How much National Insurance you pay |
| Student loan repayments | GOV.UK — Repaying your student loan: what you pay |
| Dividend tax | GOV.UK — Tax on dividends |
| Capital Gains Tax | GOV.UK — Capital Gains Tax rates and allowances |
| VAT | GOV.UK — VAT rates |
| Corporation Tax | GOV.UK — Corporation Tax rates |
| Stamp Duty Land Tax | GOV.UK — SDLT residential property rates |
| Vehicle tax (VED) | GOV.UK — Vehicle tax rate tables |
| High Income Child Benefit Charge | GOV.UK — Child Benefit tax charge |
| Council tax Band D rates | Official 2026/27 council tax statistics: Ministry of Housing, Communities and Local Government (England), the Scottish Government (Scotland) and the Welsh Government (Wales) |
Key 2026/27 figures we apply
- Personal Allowance £12,570, withdrawn at £1 for every £2 of income above £100,000 and gone entirely at £125,140.
- Income Tax bands (England, Wales, Northern Ireland): 20% on the first £37,700 of taxable income, 40% up to £125,140, 45% above.
- Employee National Insurance: 8% between £12,570 and £50,270, 2% above £50,270.
- Employer National Insurance: 15% on earnings above £5,000.
- Student loan repayment thresholds: Plan 1 £26,900, Plan 2 £29,385, Plan 4 £33,795, Plan 5 £25,000, Postgraduate £21,000; repayments are 9% of income above the threshold (6% for Postgraduate).
A worked check
To show how we apply these rules, take a £150,000 salary. The Personal Allowance has been withdrawn completely, so taxable income is £150,000. Income Tax is £7,540 (20% of £37,700) plus £34,976 (40% of the next £87,440) plus £11,187 (45% of the remaining £24,860), which is £53,703. Employee National Insurance is £5,011, leaving take-home pay of £91,286. Our calculators and salary pages must reproduce these figures; if you see a different result, please let us know.