Payslip Checker UK 2026/27
Check if your payslip deductions are correct — find out if you are overpaying tax
How to read your payslip
Your payslip must show your gross pay, tax code, income tax deducted, and National Insurance deducted. The most common reasons for incorrect deductions are:
- Wrong tax code — emergency code (1257M1 or W1) means you are not getting your full personal allowance
- Previous overpayment — from a previous job not being reconciled
- Second job not declared — you may be on BR code (20% flat rate) when you should be on the correct progressive rate
- Student loan plan wrong — deductions on the wrong plan threshold
Frequently asked questions
Your tax code is shown on your payslip. The standard code for 2026/27 is 1257L, meaning you get the full £12,570 personal allowance. If your code is BR, D0, or D1, you are being taxed at a flat rate with no personal allowance — which may indicate an error. Contact HMRC on 0300 200 3300 or check your Personal Tax Account at gov.uk.
If this checker shows you have overpaid tax, you may be owed a refund. HMRC usually adjusts this automatically via your tax code in the next year, or issues a P800 notice. You can also claim a refund via your Personal Tax Account at gov.uk if you believe you have overpaid.
An emergency tax code (e.g. 1257L M1 or W1) is applied when HMRC does not have enough information about your income. It calculates your tax on a non-cumulative basis, meaning you may pay more tax than you should. It should be corrected by your employer once HMRC has your full tax record.
Worked example
An employee earns £2,917/month gross (£35,000/year) with tax code 1257L. What should their deductions be?
| Gross monthly pay | £2,917 |
| Monthly Personal Allowance (£12,570 ÷ 12) | £1,047 |
| Taxable monthly income | £1,870 |
| Expected income tax (20%) | £374/month |
| Expected NI (8% on £2,917 − £1,048) | £150/month |
| Expected total deductions | £524/month |
| Expected net take-home | £2,393/month |
If your payslip shows significantly more than £374 tax or £150 NI, contact HMRC — you may have the wrong tax code.
How the calculation works
The checker estimates expected deductions from your gross pay and tax code, then compares to what you actually paid:
- Parse tax code: Extract Personal Allowance from your tax code (e.g. 1257L = £12,570 allowance)
- Annual gross: Convert monthly or weekly gross to annual equivalent
- Expected tax: Apply 2026/27 income tax rates to taxable income (gross minus allowance)
- Expected NI: Apply 8% on earnings £12,570–£50,270 and 2% above
- Compare: Flag if actual deductions differ from expected by more than £50/year
All calculations run entirely in your browser. No data is sent to our servers, stored, or shared with any third party.
Results are estimates based on 2026/27 HMRC rates and are intended as a guide only. They do not constitute financial or tax advice. Always verify with HMRC or a qualified accountant for your specific circumstances.