The 48-hour week, breaks and night work

As a worker in the UK, your hours are protected by law. The Working Time Regulations 1998 sets clear limits on how long you can work each week, guarantees rest breaks during your shift, and ensures you have adequate time off between work days. Whether you work full-time, part-time, or on a zero-hours contract, these rules apply to you.

The 48-hour week and the opt-out

In the UK, you cannot work more than an average of 48 hours per week. This limit is calculated over a 17-week reference period, so if you work slightly longer some weeks, the total is balanced out over the period. This rule applies to all adult workers unless you have signed a written opt-out agreement with your employer.

An opt-out is a written agreement that allows you to work beyond the 48-hour average if you choose to. This is sometimes called an opt-out agreement or a waiver. It is crucial to understand that opting out is entirely voluntary. Your employer cannot force you to sign one, and you cannot be treated unfairly or penalised for refusing. The opt-out must be in writing and signed by you—verbal agreement is not enough.

If you have already signed an opt-out, you can cancel it at any time. You need to give at least seven days' notice in writing, although your agreement may specify a longer notice period of up to three months. Once you withdraw your consent, the 48-hour limit applies again.

Rest breaks during your shift

If you work more than six hours in a day, you are entitled to an uninterrupted rest break of at least 20 minutes. This could be a tea break, lunch break, or any genuine pause from work. The break must be taken during your shift, not tacked on at the very beginning or end of the day.

Your employer decides when you take the break—it does not have to be at noon or at a time you prefer—but it must give you a realistic opportunity to step away and rest. The break does not have to be paid unless your employment contract says otherwise. If you work a shift longer than six hours, say a 12-hour shift, you are still only entitled to one 20-minute break as standard. However, employers should consider offering additional breaks where work is monotonous or physically demanding.

In some circumstances—such as an emergency or shift changeovers—you may not be able to take your break at the normal time. In that case, you have the right to compensatory rest, which means taking an equivalent break later on the same day or as soon as reasonably possible afterwards.

Daily rest between working days

You have a legal right to at least 11 consecutive hours of rest between finishing one working day and starting the next. For example, if you finish work at 8pm, you should not start work before 7am the following day. This is sometimes called the 11-hour rule.

If you work shifts or split shifts (working in the morning and again in the evening, for instance), it may sometimes be impossible to take a full 11 hours uninterrupted rest. In such cases, your employer has a duty to ensure you still get adequate rest, which may come as compensatory rest taken at a later point. The spirit of the rule—giving you time to recover—must be upheld.

Weekly days off

You are entitled to at least one full day (24 hours) off every week, or alternatively 48 hours off every 14 days. This is an average right, so you may not get a full day off every single week, but over a two-week period you should have had at least two days off.

For workers under 18, the rules are stricter. Young workers must have at least 48 hours off every week, plus an extra hour of daily rest (12 hours instead of 11) and a longer break during work time (30 minutes if working more than 4.5 hours in a day).

Night workers: extra protections

If you regularly work at least three hours during the night—defined as between 11pm and 6am, unless your employer and you agree a different period—you are classified as a night worker. Night work carries additional health and safety concerns, so the law provides extra protections.

Health assessments

Before you start night work, your employer must offer you a free health assessment. This is usually a questionnaire completed by a qualified health professional, though it can include an in-person appointment if needed. Your employer must repeat this assessment at regular intervals—normally annually—while you work nights.

You are not required to take the assessment if you don't wish to, but your employer must make the offer. If a health assessment reveals that night work is harming your health, your employer should offer you suitable day work if available. If no alternative role exists, you should not simply be dismissed; your employer must explore other options.

Night work hour limits

Night workers cannot work more than an average of eight hours in any 24-hour period. This is calculated over a 17-week reference period. However, if your night work involves special hazards or heavy physical or mental strain, the stricter rule applies: you must not work more than eight hours in any 24-hour period with no averaging allowed.

Like other workers, night workers keep all their normal rights to rest breaks, daily rest, and weekly days off. The night work limit is additional protection, not a replacement for these entitlements.

If your employer is breaking the rules

If your employer is not giving you the breaks or rest you are entitled to, your first step should be to speak to your manager or supervisor and explain the issue. Many breaches are resolved informally once raised.

If talking doesn't work, raise the matter in writing through your employer's grievance procedure. Keep records of dates, times, and what was missed—for example, shifts where you worked more than six hours without a 20-minute break, or days when you had less than 11 hours' rest between shifts.

If your grievance is not resolved, you can take a claim to the Employment Tribunal. You have three months (less one day) from the date of the breach to notify ACAS, the Advisory, Conciliation and Arbitration Service, for early conciliation. ACAS will try to help you and your employer reach an agreement. If that fails, you can proceed to tribunal.

If you believe there is a serious health and safety risk—for example, you are consistently working unsafe hours or night work is harming your health and your employer has not acted—you can also report the matter to the Health and Safety Executive (HSE) or your local authority. These bodies can investigate and issue enforcement notices.

Key points to remember

• Maximum 48 hours per week on average (17-week period) unless you have signed a written, voluntary opt-out.
• One 20-minute uninterrupted rest break if you work more than six hours in a day.
• At least 11 hours' rest between finishing one shift and starting the next.
• At least one day (24 hours) off per week, or 48 hours every 14 days.
• If you are a night worker (working three hours or more between 11pm and 6am), you have the right to a free health assessment before starting and regularly afterwards.
• Night workers cannot exceed an average of eight hours per 24-hour period (or eight hours absolute for hazardous work).
• You can cancel an opt-out at any time with seven days' notice.
• Rest breaks cannot be paid work or 'on-call' time—you must be genuinely free to rest.

These protections exist to safeguard your health, safety, and well-being. Whether you are new to the UK workforce or an experienced professional, understanding your entitlements helps you recognize if something is wrong and take action. If you have questions or concerns, contact ACAS, Citizens Advice, or your trade union—all offer free guidance on working time rights.