Overtime calculator worked example
£15 an hour at time and a half is £22.50. Five overtime hours a week for 52 weeks is £5,850.00 gross. After 2026/27 income tax and employee National Insurance, £4,212.00 of that overtime is left.
The basic week is 37.5 hours, so the salary before overtime is £29,250.00 and the total is £35,100.00. The overtime sits in the basic-rate band: income tax of £1,170.00 is 20% of £5,850.00, and National Insurance of £468.00 is 8%. Together that is 28%. Take-home for the whole year is £28,791.60. In Scotland the overtime keeps £4,156.26, because the Scottish intermediate rate of 21% catches part of this pay. Income tax and National Insurance are the same engine as the salary calculator.
There is no statutory overtime rate
GOV.UK says employers do not have to pay workers for overtime. Where a contract does pay it, the contract sets the multiplier. Time, time and a quarter, time and a half and double time are the usual ones. This page does not invent a legal premium. Average pay for the total hours, including overtime hours, must not fall below the National Minimum Wage. From 1 April 2026 the National Living Wage for workers aged 21 and over is £12.71 an hour. See the hourly wage calculator and £12.71 an hour after tax.
A one-off week
Set weeks to 1 to price a single week of overtime. The tax is still the annual calculation: the year’s basic pay plus that one week, minus the tax on the basic pay alone. A weekly payroll can land a few pence away, because National Insurance is rounded on the pay period.
Frequently asked questions
Do employers have to pay overtime?
No. GOV.UK says employers do not have to pay workers for overtime. The contract sets any multiplier. Average pay for the total hours worked must still not fall below the National Minimum Wage.
How much of time and a half do you keep after tax?
£15 an hour at time and a half is £22.50. Five overtime hours a week for 52 weeks is £5,850.00 gross. On top of a 37.5-hour week, income tax on that overtime is £1,170.00 and employee National Insurance is £468.00, so £4,212.00 is left.
Is overtime taxed differently from salary?
No. Overtime is earnings. It uses the same 2026/27 income tax bands and Class 1 National Insurance as the rest of the salary. The calculator shows the extra tax on the overtime, which is often the higher of the two bands once the basic-rate band is full.