Payslip details
How to Check Your UK Payslip
Compare the Income Tax and employee National Insurance shown on your payslip with an estimate based on your gross pay, tax code, and pay frequency.
Use the correct pay period
Have your payslip to hand and check whether it is a monthly or weekly payment. Enter the gross pay for that specific period, not your annual salary or net pay.
Enter the actual deductions
Enter the Income Tax and employee National Insurance amounts shown on the payslip. Use the deductions for the same pay period as the gross pay figure.
Enter your tax code
Copy the tax code exactly as shown, including prefixes such as S or C and codes such as 1257L, BR, D0, D1, NT, or K codes. The code is used to estimate your available allowance and tax treatment.
Check the expected deductions
Select Check payslip to compare your actual Income Tax and NI with the calculator's expected values. The estimate uses standard UK assumptions for the selected pay frequency and displays the tax-code allowance used.
Interpret the result
A result within £1 is treated as broadly matching to allow for normal payroll rounding. A larger difference is shown for review, together with the separate Income Tax and NI differences and an estimated net pay figure.
Investigate unexpected differences
Check for salary sacrifice, benefits in kind, student-loan deductions, bonuses, tax-code changes, or different cumulative totals. This is an estimate and does not access HMRC records; ask your employer's payroll team or HMRC to investigate persistent differences.
Frequently Asked Questions
Is this the same as HMRC's tax code checker?
No. This tool estimates what your PAYE deductions should be based on the inputs you provide. It does not access HMRC records or verify your tax code with them. For official tax code queries, use HMRC's online service or contact them directly.
What does 'cumulative' mean on my payslip?
Cumulative means your tax is calculated on your year-to-date earnings and allowances, minus the tax you have already paid this year. This smooths out variations if your pay changes during the year. Week 1 or Month 1 basis calculates each period independently.
Why is my Income Tax different from the estimate?
Common reasons include a different tax code, pension salary sacrifice reducing your taxable pay, benefits in kind being taxed through PAYE, or your employer using different prior-period totals. Small differences under £1 are usually just rounding.
Does it support Scottish and Welsh tax codes?
Yes. Enter your tax code with the S prefix for Scottish or C prefix for Welsh rates. The checker uses the appropriate versioned tax bands for the selected tax year.
What if my payslip shows a K code?
K codes mean your deductions (such as untaxed benefits or tax owed from a previous year) exceed your personal allowance. The K code adds an amount to your taxable pay instead of reducing it. Enter the full K code as shown on your payslip.
Can I check a bonus or irregular payment?
Yes. Enter the gross pay for the specific period in which the bonus was paid, along with the correct period number and prior totals. The checker will calculate the expected deductions for that period.