How is overtime taxed in the UK?

Overtime is taxed exactly like the rest of your pay: there's no special 'overtime tax'. What changes is the band the extra pay falls into.

If your overtime tips part of your income over the £50,270 higher-rate threshold, that slice is taxed at 40% plus 2% National Insurance, so the take-home on those hours is lower than on your base pay.

The practical question is your keep-rate — how much of each overtime pound reaches your pocket. For a basic-rate worker that's about 72p; once you're into higher rate it falls to roughly 58p.

Salary sacrifice (for example into a pension) reduces the pay that's exposed to the higher band, which is one reason it's worth modelling before you commit to extra hours.