Working Hours in the UK: The 48-Hour Week, Opt-Outs and Your Rights

Most UK workers can't be made to work more than 48 hours a week on average, though you can opt out in writing. Here is how the average works, what counts as working time, night work, under-18 limits, full-time and part-time hours and your holiday entitlement.

By Tony Musso on Thu Oct 22 2026

There is no single number of hours everyone in the UK works. What the law does is set limits: how many hours you can be asked to work on average, how much rest you get, how much night work is allowed and how much paid holiday you are owed. Most of this comes from the Working Time Regulations 1998.

This guide explains the 48-hour week and how the average is worked out, opting out and opting back in, the jobs where different rules apply, night work, the limits for under-18s, what full-time and part-time mean and your holiday entitlement.

The 48-hour week

Most workers can't be made to work more than 48 hours a week on average. The key word is average. It is normally worked out over a 17-week period, so you can work more than 48 hours in some weeks as long as the average over the period stays at or below 48.

Here is a simple example. Over 17 weeks you work 55 hours a week for 12 weeks and 30 hours a week for the other 5:

• 12 x 55 = 660 hours
• 5 x 30 = 150 hours
• 810 hours ÷ 17 weeks = an average of 47.6 hours a week

That is within the limit, even though most weeks were well over 48. Some jobs use a longer reference period, and a workforce or collective agreement can extend it, so check what applies where you work.

The limit applies to employees and workers, including most agency and zero-hours staff. It doesn't apply if you are genuinely self-employed.

What counts as working time

Working time generally includes:

• time you spend doing your job, including paid and some unpaid overtime you are asked to do
• job-related training
• travel that is part of the job, for example a care worker or engineer travelling between appointments
• working lunches, such as business lunches
• time on call when you have to be at your workplace

It generally doesn't include:

• rest breaks when no work is done
• your normal commute between home and a fixed workplace
• unpaid overtime you volunteer for
• evening or day-release classes that aren't part of the job

If you have no fixed workplace, for example you travel to different customer sites each day, travel from home to your first job and from your last job home can count as working time.

Opting out of the 48-hour week

If you are 18 or over, you can choose to work more than 48 hours a week on average by signing an opt-out agreement. The rules are:

• It must be in writing and signed by you. A verbal agreement isn't enough.
• It must be voluntary. Your employer can ask, but you can't be dismissed or treated unfairly for refusing to sign.
• It can be for a set period or indefinitely.
• You can cancel it whenever you want, even if it is in your contract. You need to give at least 7 days' notice, or longer (up to 3 months) if your opt-out agreement says so.

Opting out of the weekly limit doesn't remove your other rights. You are still entitled to rest breaks, daily and weekly rest and paid holiday. Our guide to rest breaks at work covers those.

Who can't opt out

Some workers can't opt out of the 48-hour limit. GOV.UK lists, for example, airline staff, workers on ships or boats, many workers in the road transport industry, other staff who travel in and operate vehicles covered by EU rules on drivers' hours, such as bus conductors, and security guards on vehicles carrying high-value goods. Drivers usually have their own drivers' hours rules as well, so check GOV.UK for your job.

Under-18s can't opt out either (see below).

Jobs where the 48-hour limit works differently

In some jobs you may have to work more than 48 hours a week on average without signing an opt-out. These include jobs where 24-hour staffing is needed, the armed forces, emergency services and police, security and surveillance, domestic work in a private household, many jobs at sea or on inland waterways, and jobs where you control your own working time, such as a managing executive who decides their own hours.

More than one job

The 48-hour average applies to your total working time, not each job separately. If two jobs together take you over the limit, you can either sign an opt-out or reduce your hours. Employers have a duty to keep records of working time, so tell them about other work if you are asked.

Night work

You count as a night worker if you regularly work at least 3 hours during the night period. The night period is usually 11pm to 6am, though your contract can set a different 7-hour period that includes midnight to 5am.

Night workers shouldn't work more than an average of 8 hours in each 24-hour period, usually averaged over 17 weeks. You can't opt out of this limit individually, although it can be changed by a collective or workforce agreement. If your night work involves special hazards or heavy physical or mental strain, the 8 hours is a firm limit in any 24 hours rather than an average.

Your employer must offer night workers a free health assessment before they start night work and regularly afterwards.

Working hours for under-18s

Young workers, meaning those over school leaving age but under 18, can't usually work:

• more than 8 hours a day
• more than 40 hours a week

These hours can't be averaged out, and young workers can't opt out. They also can't normally work at night, generally between 10pm and 6am, or between 11pm and 7am if their contract runs past 10pm, although some jobs are exceptions.

Children still of school age have a separate, stricter set of rules. Our guide to whether 15-year-olds can work in the UK covers those.

What counts as full-time?

There is no legal definition of full-time work in the UK. Full-time workers usually work 35 hours or more a week, and many office contracts are 37.5 hours (five days of 7.5 hours). Your contract should state your normal hours.

Part-time workers' rights

Part-time workers mustn't be treated less favourably than comparable full-time colleagues just because they work part time, unless the employer can justify it. In practice that means the same hourly rate, holiday and pension benefits on a pro rata basis, and the same access to training, promotion and career opportunities. Our guide to part-time jobs in the UK explains pro rata pay and the kinds of roles that suit shorter hours.

Overtime

There is no legal right to be paid extra for overtime, and whether overtime is compulsory depends on your contract. What the law does require is that your pay, divided by the hours you actually work in a pay period, doesn't fall below the minimum wage for your age. Long unpaid hours on a modest salary can break that rule, so keep a note of your real hours.

Holiday entitlement

Almost all workers are entitled to 5.6 weeks of paid holiday a year:

• If you work 5 days a week, that is 28 days.
• Statutory entitlement is capped at 28 days, so someone working 6 days a week also gets 28.
• Your employer can include bank holidays in your 28 days. There is no automatic right to have bank holidays off.
• Part-time workers get 5.6 weeks pro rata. Someone working 3 days a week gets 16.8 days.

If you have irregular hours or work only part of the year, for example on a zero-hours contract or in term-time-only work, holiday for leave years starting on or after 1 April 2024 builds up at 12.07% of the hours you work in each pay period. GOV.UK has a holiday entitlement calculator.

Changing your hours

If you want to work fewer hours, different days or from home, all employees can make a flexible working request from their first day in a job. Our flexible working request page shows you how to write one. If you are looking for a role that works around home life, our list of work from home jobs is a good place to start.

This guide is general information, not legal advice. Some rules differ by job and sector, so check GOV.UK or speak to Acas about your own situation.

Write a flexible working request

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