Working an extra hour does not always mean earning an extra hour of pay. In the UK, overtime pay rights depend on what your contract promises, how much you earn across the hours you actually work, and the limits on working time.
The central distinction is between a right to an overtime premium and a right to be paid lawfully. UK law does not generally guarantee time-and-a-half, or even separate overtime pay, but an employer cannot ignore contractual promises or minimum-wage requirements.
When must an employer pay for overtime?
Overtime usually means hours worked beyond the normal hours set by your employment contract. There is no general legal requirement for employers to offer a higher rate for those hours. Some contracts pay the normal hourly rate, others offer an enhanced rate, and some salaried roles include reasonable additional hours within the agreed salary.
Payment becomes enforceable where it is promised by the contract, a binding collective agreement, or another applicable contractual term. Written policies and established workplace practices can also matter, depending on their wording and circumstances. Employers should set out what counts as overtime and the applicable rate in the written statement of employment particulars. When checking your own entitlement, start with your employment contract terms, including approval requirements and weekend rates.
How unpaid overtime can breach minimum-wage rules
Even where a contract allows unpaid overtime, the employer must still meet the National Minimum Wage or National Living Wage for the relevant working hours and pay reference period. Extra hours can push the effective rate below the legal minimum, particularly for workers on modest fixed salaries.
From 1 April 2026, the National Living Wage for workers aged 21 and over is £12.71 an hour. Different rates apply to younger workers and eligible apprentices. The correct assessment uses minimum-wage rules for the type of work and relevant pay period, not simply the annual salary divided by contractual hours.
A practical overtime pay example
Imagine an employee aged 25 receives £600 gross for a week that normally involves 40 hours. Their headline rate appears to be £15 per hour. If they actually work 50 qualifying hours for the same pay, the simple average drops to £12 per hour, below the £12.71 threshold. Assuming that pay and all those hours count in that pay period, this indicates a minimum-wage problem.
This illustrates the risk, not a complete payroll calculation. Salaried-hours work has special rules, while certain deductions, allowances and overtime premiums affect the figures. Keep records and use the official minimum-wage calculator when checking a suspected shortfall. Understanding minimum wage rights in the UK helps even where extra hours are called voluntary.
Are overtime rates legally fixed?
No. There is no universal UK overtime rate of time-and-a-half or double time. An employer may offer those rates contractually, but they are not a default legal entitlement. Nor is there an automatic right to extra pay just because work falls on a Sunday, night shift or bank holiday. Where an enhanced rate is contractually agreed, however, an employer cannot simply ignore it.
Can your employer insist on compulsory overtime?
Compulsory overtime normally needs a contractual basis. If your agreement requires reasonable additional hours, the employer may be able to insist on them within that clause and the law. Where the contract does not require overtime, a request for extra shifts is not automatically an obligation.
There are working-time protections too. Most adult workers must not work more than an average of 48 hours per week, usually measured over 17 weeks, unless a valid exception or voluntary written opt-out applies. An employer must not dismiss or unfairly treat someone for refusing to sign an opt-out. Specific sectors have separate restrictions, and workers under 18 face tighter limits. An opt-out does not remove wage rights or applicable rest protections; working time and rest breaks are separate issues from payslip calculations.
What about time off in lieu and part-time work?
Some workplaces offer time off in lieu, often called TOIL, instead of overtime payment. The arrangement should explain how hours are earned, approved and taken. TOIL does not automatically cure a minimum-wage underpayment, so employers must still check what was paid for the relevant hours.
Part-time workers are generally protected against less favourable treatment compared with comparable full-time workers. However, an enhanced overtime rate may not become payable until the part-time worker exceeds normal full-time hours, depending on the contract and circumstances. Working beyond contracted part-time hours can still attract ordinary hourly pay.
Regular overtime payments can also affect statutory holiday pay calculations. Acas explains that relevant overtime payments regularly received during the previous year must be reflected in applicable holiday-pay entitlement, with rules varying by worker category.
What to do when overtime has not been paid
Start with evidence rather than assumptions. Compare your contract, rotas, clock-in records, emails requesting extra work and payslips. Write down dates, actual start and finish times, breaks, agreed rates and amounts received. Keep copies of evidence where lawful and appropriate.
Then ask your manager or payroll team for a written explanation, identifying whether the problem is an unpaid contractual entitlement, a minimum-wage shortfall or both. If informal contact does not resolve it, use the grievance procedure. In England, Scotland and Wales, seek guidance from Acas; in Northern Ireland, contact the Labour Relations Agency. Suspected minimum-wage breaches can also be reported through government channels.
Do not delay getting advice about a claim. In Great Britain, for most employment tribunal claims involving problems arising on or after 1 October 2026, the usual limit is six months minus one day. Earlier problems may still fall under the previous three-month rule. Northern Ireland has different tribunal procedures and most claims generally have a three-month deadline. Exceptions apply, and early conciliation requirements can affect timing.
Frequently asked questions
Is unpaid overtime illegal in the UK?
Not automatically. It may be lawful where the contract does not promise separate payment and the worker still receives at least the applicable minimum wage. Unpaid overtime may become unlawful if it breaches a contractual entitlement or causes minimum-wage underpayment.
Can my employer make me work late without extra pay?
That depends on the contract and circumstances. A clause requiring reasonable additional hours may allow it, subject to minimum-wage and working-time protections. A request alone does not always make overtime compulsory.
Do salaried employees qualify for overtime pay?
They can. Salary does not remove contractual overtime rights or minimum-wage protections. Check the employment terms and the rules for calculating actual hours under the relevant minimum-wage work category.
Must weekend overtime be paid at double time?
No. Enhanced weekend or bank-holiday pay usually comes from a contract or another binding arrangement, not a universal statutory rule. Check the stated overtime rates before accepting a shift.
Conclusion
UK overtime rights sit at the intersection of contracts, actual earnings and working-hour limits. First establish what pay was agreed, then count the hours worked and check whether the legal wage floor has been met. If those figures do not add up, raising the issue promptly and preserving records provides a strong starting point for resolving it.
