Overtime Pay Calculator

There is no statutory UK right to enhanced overtime pay — it depends entirely on your employment contract. Common overtime rates are time-and-a-half (1.5× your normal hourly rate) and double time (2× your normal hourly rate). Some contracts pay overtime at the standard rate or offer time off in lieu instead.

For tax purposes, overtime pay is treated identically to regular earnings. It is added to your normal pay in the period it is received and taxed at your marginal income tax rate plus National Insurance. This means high overtime in one period can push you into a higher tax bracket temporarily.

This calculator works out your overtime earnings at the specified premium rate, then calculates the tax and NI on the extra income. Enter your standard hourly rate, the overtime premium and the number of extra hours to see both the gross and net overtime pay.

Overtime pay rules in the UK. UK law doesn't require overtime premiums — overtime can be paid at the same hourly rate (must still meet National Minimum Wage). Higher rates depend on your contract. Common contractual rates: time-and-a-half (1.5×) for over 40 hrs/week, double-time (2×) for Sunday work or bank holidays. Some sectors (manufacturing, NHS, public sector) have collective agreements specifying rates. Always check your contract.

Voluntary vs guaranteed overtime — legal status. Guaranteed overtime: employer must offer, employee must accept — treated as part of normal pay for holiday pay and SMP purposes. Voluntary overtime: employer offers, employee can refuse — also counts as normal pay if consistently worked (Bear Scotland 2014, Lock v British Gas 2016, Williams v Brunel University 2017). Non-guaranteed overtime that's only occasionally offered: separate from normal pay calculations.

Working Time Directive — the 48-hour limit. UK Working Time Regulations 1998 limit work to 48 hours per week averaged over 17 weeks. Workers can 'opt out' in writing (still legal in the UK post-Brexit). Cannot opt out: under-18s, transport workers (separate rules), security guards, doctors-in-training. Health and safety requirement: 11 hours rest between shifts, 24 hours rest per week (or 48 hrs per 2 weeks). Many UK office workers opt out by signing employment contracts including the opt-out clause.

Overtime and tax. Overtime is taxed as ordinary income — no special treatment. The 'cumulative PAYE' calculation may show a higher tax rate on the overtime payment if it pushes you into a higher band for that month. Year-end balances out. Avoid excessive single-month overtime if it tips you into the £100k Personal Allowance taper or HICBC threshold for that tax year. Salary sacrifice large overtime into pension if approaching these cliffs.