Statutory Sick Pay Underpayment Calculator

Statutory Sick Pay Underpayment Calculator

SSP rules changed dramatically on 6 April 2026 — day-one entitlement, no minimum earnings, and 80% of pay for lower earners. If your employer didn’t apply the new rules, you may be owed back-pay. Use this to estimate what you should have received.

Your average weekly earnings (£, before tax)

Take your usual gross weekly pay. If you’re paid monthly, divide your monthly gross by 4.33.

Qualifying days you work per week 5 days (Mon–Fri standard) 4 days 3 days 2 days 1 day 6 days 7 days How many qualifying days were you off sick?

Only count days you’d normally have worked. Maximum 196 days (28 weeks of a 7-day work week, less for fewer days).

Total SSP you actually received from employer (£)

Check payslips for the period you were off sick. If your employer paid you nothing, enter 0.

Calculate underpayment

Based on 2026/27 rules effective from 6 April 2026: weekly SSP is the lower of £123.25 or 80% of average weekly earnings. SSP is paid from day one of sickness for up to 28 weeks. Source: GOV.UK Statutory Sick Pay.