2026/27 tax and NI check

Reviewed 20 July 2026. This broad comparison uses bundled 2026/27 Income Tax and employee National Insurance assumptions. It is designed to flag a line worth checking, not to replace a payroll calculation.

Check current Income Tax rates and National Insurance contribution rates. Check your tax code notice, payroll portal and full payslip if the difference matters.

How to use the payslip checker

Copy the gross pay, tax, NI, pension and net pay lines from one payslip. The checker annualises the period, estimates Income Tax and NI, then converts the result back to the same payslip period.

The inline result table shows estimated, actual and difference columns for Income Tax, National Insurance and net pay. A positive difference means the amount entered is higher than the broad estimate for that period. A negative difference means it is lower than the estimate.

What differences can mean

Differences can come from tax codes, payroll timing, bonus periods, statutory pay, taxable benefits, student loan notices or pension setup.

Not a payroll audit

This is a broad estimate for spotting lines worth checking. It does not replace employer payroll records, HMRC notices or professional advice.

Source notes

Income Tax and National Insurance estimates use the bundled Clear Calculators UK tax data, checked against official guidance in June 2026.

Common reasons a payslip may not match

Payroll systems often know details that a quick checker cannot see. A changed tax code, previous pay in the tax year, a new starter calculation, taxable benefits, statutory sick pay, maternity pay, bonus timing, salary sacrifice, pension method, student loan notices and payroll rounding can all move the real payslip away from a broad estimate.

Use the checker as a sense-check when something looks unusual, such as a tax line that jumps after a bonus or a pension line that does not reduce taxable pay in the way you expected. If the difference is material, compare against your full payslip, payroll portal, P45/P60 information and HMRC account before assuming there is an error.

What to do when the difference looks large

Start by checking that the pay period, gross pay and pension treatment match the payslip. A monthly payslip entered as annual pay, or a salary sacrifice pension entered as an after-tax pension, can make the comparison look wrong even when the payslip is fine.

If the inputs look right, compare the payslip against recent changes: a new job, changed tax code, bonus, overtime, unpaid leave, statutory pay, student loan start notice or pension adjustment. The checker is best used to narrow down which line needs attention before contacting payroll.

Small differences

A few pence or pounds can come from payroll rounding, pay-period thresholds or the order in which deductions are applied.

Repeated differences

If the same line is different every pay period, check the tax code, pension method, NI category and student loan plan first.

One-off differences

A bonus, correction, arrears payment, unpaid day or taxable benefit can make one payslip look unusual without changing the normal pattern.