Why does my NHS payslip look wrong? 6 common AfC calculation errors
NHS payslip errors are more common than most people realise. Here are the 6 most frequent AfC calculation mistakes — and how to check if you're being underpaid.
If your NHS payslip has ever made you stop and stare — suspecting the number isn’t right but not knowing where to look — you are not alone. NHS Agenda for Change pay calculations involve multiple interacting variables: your band, your pay point, your shift pattern, your pension tier, and the correct enhancement rates for each type of unsocial hour you work.
Errors happen. This guide explains the six most common mistakes, how to identify them on your own payslip, and what to do if you find one.
1. Wrong enhancement rate applied
AfC enhancement rates differ by band:
- Bands 1–3: Nights and Saturdays +37%, Sundays and bank holidays +74%
- Bands 4–9: Nights and Saturdays +30%, Sundays and bank holidays +60%
The most common error is applying Band 4–9 rates to Band 1–3 staff, or vice versa. Check your band on your contract, then verify the rate used in your payslip breakdown.
How to check: Your hourly rate (annual salary ÷ 52 ÷ 37.5) multiplied by the correct enhancement percentage should match what your payslip shows for unsocial hours.
2. Pension contribution on the wrong tier
NHS pension contributions are tiered based on your actual pensionable pay — not your band, and not your contracted salary. If your pensionable pay crossed a tier boundary during the year (due to increments, back pay, or unsocial hours), your contribution percentage should have changed.
The April 2025 tier boundaries:
- Up to £13,259: 5.2%
- £13,260–£26,831: 6.5%
- £26,832–£32,691: 8.3%
- £32,692–£49,078: 9.8%
- £49,079–£62,268: 10.7%
- Above £62,268: 12.5%
If you received an increment in April and your employer did not update your pension tier, you may be on the wrong rate.
3. Increment not applied on the correct date
AfC increments are applied annually on your increment date — not on 1 April. Many trusts have a history of applying increments late. Even a month’s delay means you were paid at a lower rate than your entitlement.
If you crossed an increment point and your basic pay did not change, raise this with payroll immediately. You are entitled to backdated pay to your correct increment date.
4. Bank holiday pay applied incorrectly
Bank holidays on AfC attract the Sunday enhancement (the higher rate). Some trusts — particularly when using bank or agency staff management systems — apply the Saturday rate in error.
Check every bank holiday in your payslip period. If you worked Christmas Day, New Year’s Day, or any other bank holiday, the enhancement should be 74% (Bands 1–3) or 60% (Bands 4–9) — the same as Sunday.
5. Wrong contracted hours used in hourly rate calculation
Your hourly rate is your annual salary divided by 52 weeks divided by your contracted weekly hours. NHS standard full time is 37.5 hours, not 40.
If your employer has calculated your hourly rate using 40 hours, every single payment — basic and enhanced — is slightly too low. It’s a small error per shift but compounds significantly over a year.
Check: Take your annual salary from your contract. Divide by 52. Divide by 37.5 (or your contracted part-time hours). That is your correct hourly rate.
6. Overtime calculated at the wrong rate
AfC overtime is paid at plain time (your basic hourly rate, no enhancement) for the first 8 hours of overtime worked in a month, then time and a half thereafter. Some trusts apply the wrong threshold or enhancement to overtime hours.
If you regularly work overtime, check the rate line on your payslip against this rule.
What to do if you find an error
- Calculate what you believe you should have been paid (ShiftSlip will do this for you)
- Identify the specific rule that was breached — cite the AfC handbook section
- Raise a formal payroll query in writing — email, not verbal
- If unresolved in 4 weeks, escalate to your line manager and RCN/Unison rep
- Keep a record of all correspondence
You are entitled to backdated correction for underpayments. There is no time limit on recovering underpaid wages in the UK under the Employment Rights Act.
ShiftSlip calculates your NHS take-home pay shift by shift, using your actual band, pay point, and pension tier. Join the waitlist and be first to check your payslip when we launch.