The Working Time Regulations: hours, rest, night work and the opt-out
The 48-hour week and how to opt out of it, daily and weekly rest, breaks, night work limits, young workers, and the records you have to keep.
Reviewed September 2026. Guidance, not legal advice: employment law moves, so check the current position before relying on any of it.
The Working Time Regulations set the maximum week, the minimum rest and the paid holiday for almost every worker in Britain. The 48-hour limit is the part people know, and the part with the opt-out. The rest and break rules have no opt-out, apply to everyone, and are where a busy site or shop most often falls short without noticing.
This guide covers the limits, the exceptions that matter to small employers, night work, young workers and record keeping. Paid holiday has its own guide.
The 48-hour week
A worker's average working time, including overtime, must not exceed 48 hours a week, averaged over a 17-week reference period (26 weeks in some sectors, or up to 52 by collective or workforce agreement). Working time is time working at the employer's disposal and carrying out duties: it includes travel between jobs, working lunches and required training, and excludes the commute, rest breaks and time on call away from the workplace when not working.
The limit is an average. A 60-hour week followed by three 40-hour weeks is inside it. Sixty hours every week is not, unless the worker has opted out.
The opt-out
An adult worker may agree in writing to work more than the average 48 hours. The agreement must be voluntary, individual (not buried in a collective agreement), and terminable by the worker on seven days' notice, or up to three months if the agreement says so. A worker cannot be dismissed or treated badly for refusing to sign or for withdrawing; both are automatically unfair and unlawful detriment.
Keep a list of who has opted out. You no longer have to record the actual hours of opted-out workers, but you must still be able to show you are complying with rest and night work limits for them.
Rest and breaks
These apply to every adult worker with no opt-out. Where the work genuinely prevents them (a shift that cannot be left, continuous production, an emergency), the worker must be given compensatory rest of equivalent length as soon as possible afterwards. "Too busy" is not one of the exceptions.
- Daily rest: 11 consecutive hours in each 24-hour period.
- Weekly rest: 24 uninterrupted hours in each seven days, or 48 hours in each 14 days.
- Rest break: 20 minutes, uninterrupted, away from the workstation, when the working day exceeds six hours. Unpaid unless the contract says otherwise. It cannot be at the start or end of the shift.
Night work
A night worker is someone who normally works at least three hours of their daily working time during the night period (11pm to 6am unless agreed otherwise). Night workers' normal hours must not exceed an average of eight in any 24-hour period over the reference period, and where the work involves special hazards or heavy physical or mental strain, eight hours is an absolute limit on any night. Night workers are entitled to a free health assessment before starting nights and at regular intervals, and to be transferred to day work where a doctor advises the night work is harming their health.
Young workers
Workers aged 16 and 17 (over school leaving age, under 18) have stricter limits with almost no flexibility:
- Maximum eight hours a day and 40 hours a week, not averaged.
- No night work between 10pm and 6am (or 11pm and 7am), with narrow exceptions.
- Daily rest of 12 consecutive hours; weekly rest of 48 hours.
- A 30-minute break when the working day exceeds four and a half hours.
Who is excluded
Genuinely self-employed people; workers whose working time is not measured or predetermined and who control it themselves (senior managers, some family businesses); mobile workers in road transport, who have their own rules; and a set of partial exceptions (security, continuity of service, seasonal peaks) that alter the rest rules but not the 48-hour average. The exceptions are narrow and read narrowly. Most site and shop staff are inside every rule.
Records
Employers must keep adequate records to show that the 48-hour limit and the night work limits are complied with, for two years. Following the 2024 reforms, this does not require a daily log of every worker's hours where you can demonstrate compliance another way, but for hourly staff the clock records are the simplest evidence and you have them anyway. Keep the opt-out agreements and the night worker health assessments with them.
Enforcement
The Health and Safety Executive (or the local authority) enforces the working time limits and can serve improvement notices and prosecute. Rest breaks and holiday are enforced by workers in the tribunal. Dismissal or detriment for asserting any of these rights is automatically unfair and unlawful from day one.
The checklist
- Know who works more than 48 hours on average; opt-outs in writing, individually, with the withdrawal right stated.
- 11 hours between shifts, 24 hours off in seven; rota built to deliver both.
- 20-minute break scheduled into every shift over six hours; compensatory rest where it is missed.
- Night workers identified; health assessments offered and recorded; eight-hour average respected.
- Under-18s rostered to the young worker limits.
- Records kept two years; clock data does most of it.
What the law says
- Working Time Regulations 1998: reg.4 (48 hours), reg.5 (opt-out), reg.6 (night work), reg.7 (health assessments), regs.10 to 12 (rest and breaks), reg.9 (records), regs.18 to 24 (exceptions and compensatory rest), reg.5A and 6A (young workers).
- Employment Rights Act 1996 ss.45A and 101A: detriment and automatically unfair dismissal for asserting working time rights.
- Employment Rights (Amendment, Revocation and Transitional Provision) Regulations 2023: the 2024 clarifications on record keeping.
Questions people ask
Can I make the opt-out a condition of the job?
You can ask; you cannot insist, and you cannot refuse to hire or dismiss because someone will not sign. In practice, an opt-out signed under pressure at induction is the one a tribunal looks at hardest.
Do I have to pay for the 20-minute break?
No, unless the contract says so. Many employers do because it is simpler. What you cannot do is count an unpaid break as working time for the minimum wage, or make the worker take it at their workstation.
Our lads want to work six long days to get the job done. Can they?
If they have opted out, the weekly hours are theirs to decide. The rest rules still apply: 11 hours between shifts and 24 hours off in seven. Six twelve-hour days with Sunday off fits; seven does not, and neither does a 14-hour day that leaves less than 11 hours before the next.
The admin this guide describes, done for you
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