The UK Working Time Directive is implemented through the Working Time Regulations 1998 (WTR), which set maximum weekly working hours, minimum rest periods, and annual leave entitlements. The headline rule is that a worker’s average working time must not exceed 48 hours per week over a 17-week reference period — but workers can sign an opt-out agreement to work more. Every worker is entitled to a minimum of 5.6 weeks’ paid annual leave (28 days for a full-time worker), and daily and weekly rest breaks are mandated. The employer must keep adequate records to show compliance.

This guide covers the 48-hour week, the opt-out mechanism, rest breaks, annual leave, and the practical compliance requirements.

Key takeaways

  • The Working Time Regulations 1998 implement the EU Working Time Directive in UK law — the 48-hour week, rest breaks, and annual leave entitlement.
  • Workers’ average working time must not exceed 48 hours per week over a 17-week reference period.
  • Workers can sign a written opt-out agreement to work more than 48 hours, but cannot be required or pressured to sign.
  • Every worker is entitled to 5.6 weeks’ paid annual leave per year (28 days for a full-time worker, which can include bank holidays).
  • Daily rest: at least 11 consecutive hours in every 24-hour period. Weekly rest: at least 24 uninterrupted hours in every 7-day period.
  • Employers must keep records for 2 years to demonstrate compliance.

The 48-hour week

Under regulation 4 of the Working Time Regulations 1998, a worker’s average working time, including overtime, must not exceed 48 hours per week.

How the average is calculated

The 48-hour limit is averaged over a reference period of 17 weeks. This means a worker can work more than 48 hours in some weeks, provided the average over the reference period does not exceed 48 hours.

Example: A worker averages 50 hours per week for 10 weeks and 46 hours per week for 7 weeks. The average over 17 weeks is: (500 + 322) / 17 = 48.35 hours — this exceeds the limit.

Where there is a relevant collective agreement, the reference period can be extended to 26 weeks.

What counts as working time

Working time includes any period during which the worker is:

  • Working
  • At the employer’s disposal
  • Carrying out their activities or duties

It includes time on training, travelling for work (not commuting), on-call time (where the worker is required to be at or near the workplace), and overtime.

The opt-out

A worker aged 18 or over may agree in writing to work more than 48 hours per week — regulation 5. The opt-out must be:

  • Voluntary — the worker cannot be required or pressured to sign.
  • In writing — a clear, specific, signed agreement.
  • Revocable — the worker can give at least 7 days’ notice to withdraw the opt-out (or longer if a longer notice period is agreed, up to a maximum of 3 months).

The opt-out does not remove the employer’s obligation to ensure the worker’s health and safety. If the hours are genuinely damaging the worker’s health, the employer must take action regardless of the opt-out.

Rest breaks and rest periods

Daily rest

Under regulation 10, every worker is entitled to an uninterrupted rest period of at least 11 consecutive hours in every 24-hour period.

Weekly rest

Under regulation 11, every worker is entitled to an uninterrupted rest period of at least 24 consecutive hours in every 7-day period — in addition to the daily rest.

If the worker has not received their full daily or weekly rest, the employer must make up the deficit as soon as possible.

In-work rest breaks

Under regulation 12, a worker who works more than 6 hours in a day is entitled to a rest break of at least 20 uninterrupted minutes. The break need not be paid unless the contract provides for it.

Annual leave entitlement

Under regulation 13, every worker is entitled to 5.6 weeks’ paid annual leave per year. For a full-time worker working 5 days a week, this equals 28 days. For a part-time worker, the entitlement is pro rated — 5.6 × the number of days worked per week.

Can bank holidays be included?

Yes. An employer can include bank holidays within the 5.6 weeks’ entitlement. A full-time worker who receives 20 days’ leave plus 8 bank holidays has met the minimum.

Carry-over

Under regulation 13(9)–(10), where a worker has been unable to take annual leave because of sickness, the leave can be carried forward. The employer must allow the worker to take the leave at a later date.

Under the COVID-related amendments (now lapsed), additional carry-over rules applied. The general rule is that unused leave should be taken in the leave year to which it relates, but the employer must not deter or prevent the worker from exercising the right.

Payment in lieu

The employer can only pay in lieu of untaken statutory leave on termination of employment — during employment, statutory leave must be taken as leave.

Night work

Under regulation 6, night workers’ average working time must not exceed 8 hours per 24-hour period over a 17-week reference period. Night work is defined as work between 11pm and 6am (or as defined in a collective agreement).

Night workers must also receive a free health assessment before starting night work and at regular intervals thereafter.

Record-keeping

Under regulation 14, employers must keep records that are adequate to show whether the limits on working time, rest breaks, and annual leave are being complied with. Records must be kept for 2 years.

The records do not need to show exact hours for every worker — the employer can rely on a system that provides adequate information to show compliance (e.g., an opt-out agreement combined with records that demonstrate the employer has no reason to believe the limits are being breached).

Common pitfalls

1. Pressuring workers to sign opt-outs

An opt-out that is signed under pressure — or as a condition of employment — is not valid. The worker must be genuinely free to refuse.

2. Ignoring overtime in the calculation

Overtime counts towards the 48-hour average. An employer who only counts contracted hours and ignores regular overtime is not complying with the Regulations.

3. Failing to track night work hours

Night workers have a separate 8-hour limit. An employer who does not track night work hours separately from overall hours is exposed to liability.

4. Assuming the 48-hour limit applies only to contracts over 48 hours

The 48-hour limit applies regardless of the contractual hours. If a worker on a 40-hour contract regularly works 15 hours of overtime, the average may exceed 48 hours.

Putting it into practice

Five steps to comply with the Working Time Regulations:

  1. Track actual hours worked — including overtime, training, and on-call time — against the 17-week reference period.
  2. Maintain opt-out records — for every worker who has signed an opt-out, keep the signed document and the revocation date if applicable.
  3. Monitor night work hours — track night work separately and ensure the 8-hour average is not exceeded.
  4. Check annual leave balances — ensure workers are taking their 5.6 weeks’ leave and not being discouraged from doing so.
  5. Keep records for 2 years — HMRC can inspect records, and the employer must be able to show compliance.
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Sources

This article is general information, not legal advice. Working time law is complex and fact-specific — consult Acas or an employment solicitor for specific situations.