Enter the figures from your payslip. We compute what each line should look like for 2026/27 and highlight anything that falls outside normal tolerance. This is an educational guide, not a definitive audit — payroll calculations depend on information we may not know, so treat flags as "worth asking payroll about", not as evidence that payroll is wrong.
Your payslip figures
Pick the one that matches your payslip period.
Scottish taxpayers normally have an S-prefix tax code, but the "Scottish taxpayer" status is set by HMRC based on your main home address and may apply regardless of the code shown. If in doubt, pick the setting that matches your HMRC Personal Tax Account.
Your contracted salary portion for the period (before overtime, bonus etc).
Payrolled benefits in kind (e.g. company car) that add to taxable pay this period only.
Auto-filled from the earnings above. Override only if your payslip shows a different "Total gross".
Pension & salary sacrifice
Non-pension sacrifice (cycle-to-work, EV scheme, holiday purchase). Reduces taxable + NI pay.
Statutory deductions
Other deductions
Union subs, season ticket loan, court order, give-as-you-earn, share scheme, overpayment recovery, etc. Enter the combined total.
Net pay received
What actually hit your bank account.
Nothing you type leaves your browser. We don't store or transmit any payslip values. Analytics only records which lines triggered a flag, never the amounts.
Verdict
Line
You entered
We expected
Status
Expected figures use the published 2026/27 PAYE and NI bands with cumulative PAYE. If your payroll uses a non-cumulative basis (W1/M1 or X), expected tax can look higher or lower than the payslip — that's a timing effect, not an error.
Possible explanations
For each line that's outside tolerance, below are the common legitimate reasons it could differ, what to check on your payslip, and where to find the authoritative HMRC guidance.
Tolerance rules we used
Payroll systems round in different ways. We allow a small absolute & relative tolerance before flagging:
Line
GREEN (within)
RED (material)
What to do next
How each payslip line is calculated
Gross pay — your total earnings for the period before any deductions. Includes salary, overtime, bonuses, commission and any taxable benefits that are "payrolled" rather than put on a P11D.
Tax code — the key signal payroll uses to work out how much tax-free pay to give you each period. 1257L means £12,570 personal allowance; a K code adds taxable pay; BR taxes everything at 20%; S prefix means Scottish bands apply. Full tax code library →
PAYE Income Tax — tax deducted via Pay As You Earn. Cumulative PAYE looks at year-to-date pay & allowance; non-cumulative treats each period independently. Early in the tax year the two methods can produce visibly different results.
National Insurance — Class 1 employee NI: 8% on earnings between the Primary Threshold and Upper Earnings Limit each period, plus 2% above. Calculated per period, not annualised like PAYE.
Pension — three methods: Salary sacrifice reduces gross pay before tax and NI (saves both). Net pay reduces taxable pay before PAYE but NI is calculated on the pre-pension figure. Relief at source takes the full contribution from net pay and HMRC adds basic-rate relief into the pension pot.
Student loan — Plan 1 and Plan 2 at 9% above their respective thresholds; Plan 4 at 9%; Plan 5 at 9%; Postgraduate at 6%. Multiple plans deduct separately. Student loans overview →
Net pay (take-home) — Gross minus PAYE, NI, pension (if net-pay or sacrifice method), student & postgraduate loans, salary sacrifice and any other deductions on the payslip.
Expected figures use the 2026/27 UK tax year. Personal Allowance £12,570 (tapered £1 for every £2 over £100,000). PAYE bands: Basic 20% to £50,270, Higher 40% to £125,140, Additional 45% above. Scottish bands used when the "Scottish taxpayer" status is set. Class 1 NI: 8% between £12,570 and £50,270 annualised, 2% above.
This checker assumes cumulative PAYE. Non-cumulative (W1/M1/X) codes operate per-period and can produce different tax especially in April or after a mid-year code change. We flag material differences rather than small ones for this reason — see our full tolerance methodology →
We cannot know everything your payroll system does. Statutory Sick/Maternity Pay cycles, car-benefit payrolling, and student loan threshold changes mid-year can all legitimately move your deductions. Treat flags as "worth checking with payroll", not "payroll made a mistake".