Rotasmith

Overtime pay calculator

Work out what a week of overtime costs, at whatever multiplier you actually pay. It also checks the average across all hours still clears the minimum wage, which is the only part of overtime pay the law is strict about.

Overtime hours
8.5
Overtime pay
£165.75
Total for the week
£653.25

8.5 hours beyond 37.5, paid at 1.5× £13.00 = £19.50 an hour. Averaged across all 46 hours that works out at £14.20 an hour.

There is no legal overtime rate in the UK. Time and a half is a convention, not a right — an employer can pay plain time for extra hours unless the contract says otherwise. What the law does require is that average pay across all hours worked stays at or above the minimum wage, which is the check above.

The 48-hour week, and opting out

Separately from pay, the Working Time Regulations cap average working time at 48 hours a week over a 17-week reference period. Somebody can agree in writing to opt out, and can withdraw that agreement with notice. Anyone regularly working well over 48 hours without a signed opt-out is a compliance problem waiting to be found, and it is worth knowing before an inspector asks rather than after.

Questions

Is there a legal overtime rate in the UK?
No. There is no statutory right to a higher rate for extra hours. Time and a half is a widespread convention, not a legal requirement — what applies is whatever the contract says.
Does overtime have to be paid at all?
Extra hours must be paid, but not necessarily at a premium. The one hard rule is that average pay across all hours worked must not fall below the National Minimum Wage for the worker's age band.
Does overtime count towards holiday pay?
Regular overtime normally does. Where overtime is worked with sufficient regularity, it should be included in the 52-week average used to calculate holiday pay, following a line of UK case law.
Can an employer make somebody work overtime?
Only if the contract provides for it. Separately, most workers cannot be required to average more than 48 hours a week over 17 weeks unless they have opted out of the Working Time Regulations in writing.

Stop working this out by hand

Rotasmith compares what people clocked against what they were rostered for, so overtime is derived rather than typed. At the end of the month it exports as a file payroll can take.

See a live example

Information, not legal or payroll advice. Minimum wage rates change each April — check the current figures on gov.uk before relying on the comparison above.