UNDERSTAND YOUR NUMBERS
Official Tax & Calculation Sources
Official sources with effective dates and review dates for tax, NI, dividends, pensions, IR35 and umbrella pay.
Tax year 2026/27 · Last verified · Methodology · Official sources
Verified calculation sources
Current verified tax year: 2026/27. Next tax year 2027/28 is pending verification and is not offered as a current calculator year.
2026/27
- HMRC Income Tax, NI and student-loan thresholds — effective 6 Apr 2026 to 5 Apr 2027, last verified 5 Oct 2026.
- HMRC dividend tax — effective 6 Apr 2026 to 5 Apr 2027, last verified 5 Oct 2026.
- HMRC Corporation Tax and marginal relief — effective 6 Apr 2026 to 5 Apr 2027, last verified 5 Oct 2026.
- HMRC pension tax relief — effective 6 Apr 2026 to 5 Apr 2027, last verified 5 Oct 2026.
- HMRC off-payroll working guidance — effective 6 Apr 2026 to 5 Apr 2027, last verified 5 Oct 2026.
- Government umbrella-company guidance — effective 6 Apr 2026 to 5 Apr 2027, last verified 5 Oct 2026.
2025/26
- HMRC Income Tax, NI and student-loan thresholds — effective 6 Apr 2025 to 5 Apr 2026, last verified 5 Oct 2026.
- HMRC dividend tax — effective 6 Apr 2025 to 5 Apr 2026, last verified 5 Oct 2026.
- HMRC Corporation Tax and marginal relief — effective 6 Apr 2025 to 5 Apr 2026, last verified 5 Oct 2026.
- HMRC pension tax relief — effective 6 Apr 2025 to 5 Apr 2026, last verified 5 Oct 2026.
- HMRC off-payroll working guidance — effective 6 Apr 2025 to 5 Apr 2026, last verified 5 Oct 2026.
- Government umbrella-company guidance — effective 6 Apr 2025 to 5 Apr 2026, last verified 5 Oct 2026.
Historical rates are stored in year-specific configuration. Some guidance links show current rules; use the year-specific HMRC employer rates for historical payroll.
Single-director Employment Allowance eligibility