How this estimator works

Our tools estimate UK tax outcomes from tax-year-specific rules for self-employed planning, PAYE take-home comparison, and UK tax residency scenario analysis.

Calculation flow

  1. Taxable profit = gross self-employed income - allowable expenses - pension allowance.
  2. Income tax is calculated against stored UK tax bands with personal allowance handling.
  3. Class 2 and Class 4 NI are estimated from your taxable self-employed profit.
  4. Student loan estimate is applied when a plan is selected.
  5. Total estimated tax/NI drives take-home and monthly set-aside guidance.

Important assumptions

  • This is for planning and cashflow, not filing.
  • Scotland mode applies Scottish non-savings bands only.
  • Interest/dividend treatment is still simplified for quick estimation.
  • Payment-on-account is shown as a planning estimate.

Take-Home Pay Calculator flow

  1. Select tax year, frequency, gross pay, tax code, pension method, and student loan setup.
  2. Pension method determines how taxable pay, NI-able pay, and loanable pay are adjusted.
  3. PAYE income tax is annualised from selected frequency and then shown per period.
  4. Employee Class 1 NI and student loan deductions are calculated on pay-period basis.
  5. The tool compares salary sacrifice, net pay, and relief-at-source in one view.

Open the Take-Home Pay Calculator.

Take-Home tool assumptions

  • Designed for planning and payslip understanding, not payroll filing.
  • Assumes regular pay per period rather than complex year-to-date corrections.
  • Does not model directors NI, benefits-in-kind, or all payroll edge cases.
  • Student loan and NI behavior follows selected pension method logic.

Tax Residency Planner flow

  1. Add UK stay periods and select the tax year to compute day count.
  2. Set background assumptions for automatic overseas/UK tests.
  3. Tick sufficient ties and let the tool trace the decision route.
  4. Use planned-extra-days to test threshold risk before travel changes.
  5. Model split-year timeline around a move/work/home event date.

Open the UK Tax Residency Planner.

Residency planner assumptions

  • UK-only planning model based on SRT structure and selected tie inputs.
  • Outputs are planning guidance, not formal residence determinations.
  • Split-year view is scenario-based and depends on full statutory case conditions.
  • Use the rule-path output as an accountant discussion aid.