Payslip Errors: How to Spot Underpayment

Most of us glance at the "amount paid" figure and move on. But payslips are one of the few places employer mistakes, accidental or otherwise, become visible in black and white. This is how to read one, and what to do if the numbers don't add up.

What a payslip legally has to show

Every employer must give you an itemised payslip on or before payday, showing:

• Your gross pay (before deductions) and net pay (what actually lands in your account)
• The amount and reason for every deduction (tax, National Insurance, pension, student loan, etc.)
• Your hours worked, if your pay varies by hours worked

If you're not getting a payslip at all, or you're being paid cash-in-hand with nothing to show for it, that alone is worth raising. It makes every other check in this guide much harder to do.

The deductions worth checking

Tax and National Insurance deductions are standard and expected. But a few deductions are only lawful in specific circumstances:

• Till shortages or breakages. An employer generally can't just deduct these from your pay unless your contract specifically allows it and proper process is followed
• Uniform or training costs. Deducting these can be unlawful if it takes your pay below minimum wage for that pay period
• "Admin fees" or unexplained deductions. Any deduction should have a clear, agreed reason. If you can't work out what a line item is for, ask

A useful rule: any deduction that isn't tax, National Insurance, a court order, or something you've agreed to in writing is worth questioning.

The minimum wage check most people skip

It's not enough to just look at your hourly rate on paper. What matters legally is your pay divided by hours actually worked, once deductions are accounted for. This catches out people who:

• Work unpaid extra minutes before/after a shift that aren't logged
• Have uniform or equipment costs deducted, effectively lowering their real hourly rate
• Are paid a flat daily/weekly rate that works out below minimum wage once actual hours are totalled

If your effective hourly rate (after deductions, across all hours worked), comes out below the National Minimum Wage for your age, that's a genuine underpayment, even if your contracted rate looks fine on paper.

Holiday pay errors

If you work irregular hours, holiday pay should reflect your average earnings, not just a flat rate that ignores overtime or variable shifts. Getting this calculation wrong is one of the most common payroll errors, particularly for zero-hours and part-time workers.

What to do if the numbers don't add up

• Gather your payslips and a record of hours actually worked (rotas, texts, your own notes)
• Raise it with your employer or payroll first, in writing, calmly and factually. Genuine payroll errors are common and often get fixed quickly once flagged
• If it's not resolved, HMRC enforces minimum wage law and can order back pay plus penalties. You can report a suspected underpayment to them, including anonymously
• Keep everything (screenshots, payslips, messages), in case you need it later

Our free Minimum Wage Guide walks through whether your specific situation counts as underpayment, and our letter guides explain what to include when you raise a payslip or underpayment issue with your employer formally.