Working Time Regulations UK: Hours, Breaks and Rest

The Working Time Regulations 1998 (WTR) are one of the most important — and most frequently breached — pieces of employment law in the UK. They set legal limits on how many hours employees can work, guarantee rest breaks and rest periods, and impose special rules for night workers.

Non-compliance can result in employment tribunal claims, HSE enforcement action and significant financial penalties. Yet many employers, particularly in shift-based industries, inadvertently breach the regulations every week through poor scheduling practices. This guide explains your obligations in full.

Overview of the Working Time Regulations

The WTR implement the EU Working Time Directive into UK law. Despite Brexit, the regulations remain in force and are unlikely to be significantly weakened. They apply to virtually all workers in the UK, including:

• Full-time and part-time employees
• Agency workers
• Most freelancers and casual workers (if they meet the legal definition of “worker”)
• Trainees and apprentices

Certain sectors have modified rules, including mobile workers in road transport, sea fishing, and offshore work. Members of the armed forces and emergency services have specific exemptions in certain circumstances.

The 48-Hour Maximum Working Week

The headline rule of the WTR is that a worker’s average working time must not exceed 48 hours per week, calculated over a 17-week reference period (which can be extended to 26 weeks by collective agreement or workforce agreement).

What Counts as Working Time?

Working time includes:

• Time spent carrying out work duties
• Time spent travelling as part of the job (but not the ordinary commute)
• Working lunches and required training
• Time on call at the workplace (even if not actively working)

Time on call at home where the worker is free to use the time as they wish generally does not count as working time, unless they are actually called upon to work.

The Opt-Out Agreement

The UK’s implementation of the Directive includes an individual opt-out that allows workers to agree in writing to work more than 48 hours per week. Key points about the opt-out:

• It must be voluntary — you cannot require an employee to sign one
• It must be in writing
• There is no maximum hours limit once opted out (though other health and safety duties still apply)
• The worker can cancel the opt-out by giving between 7 days and 3 months notice (as specified in the agreement)
• You must keep records of who has opted out

Important: An opt-out does not exempt the worker from rest break and rest period requirements. It only affects the 48-hour weekly limit.

Enforcement

The 48-hour limit is enforced by the Health and Safety Executive and local authorities. Workers cannot individually enforce the 48-hour limit at employment tribunal (unless they are dismissed or subjected to detriment for refusing to sign an opt-out), but the HSE can prosecute employers who fail to take reasonable steps to ensure compliance.

Rest Break Requirements

The 20-Minute Break

Workers are entitled to an uninterrupted rest break of at least 20 minutes when their daily working time exceeds 6 hours. Key points:

• The break must be taken during the shift, not at the beginning or end
• It must be uninterrupted — the worker should be free to leave their workstation
• It should be a break from work, not a brief pause in duties
• It does not have to be paid (unless the employment contract provides for paid breaks)

Common breach: Many employers in retail, hospitality and healthcare schedule shifts of exactly 6 hours to avoid the break requirement. This is lawful if the shift genuinely ends at 6 hours, but if workers routinely work beyond 6 hours (even by a few minutes), the break entitlement is triggered.

Daily Rest

Workers are entitled to a rest period of at least 11 consecutive hours in each 24-hour period. This means there must be at least 11 hours between the end of one shift and the start of the next.

Example: If a worker finishes at 11pm, they cannot start their next shift before 10am the following day.

This is one of the most commonly breached provisions. “Clopening” shifts — where a worker closes a business in the evening and opens it the next morning — frequently violate the daily rest requirement. For more on how to avoid common scheduling mistakes, see our guide to employee scheduling compliance.

Weekly Rest

Workers are entitled to an uninterrupted rest period of at least 24 hours in each 7-day period. Alternatively, employers can provide 48 hours rest in each 14-day period.

This means workers must have at least one full day off per week, or two full days off per fortnight.

Night Worker Limits

Night workers have additional protections under the WTR.

Who Is a Night Worker?

A night worker is someone who regularly works at least 3 hours during the night period (11pm to 6am, unless varied by agreement) as a normal course of their employment.

Maximum Night Working Hours

Night workers must not work more than an average of 8 hours in each 24-hour period, calculated over a 17-week reference period.

For night workers whose work involves special hazards or heavy physical or mental strain, the limit is an absolute 8 hours in any 24-hour period — no averaging is permitted.

Health Assessments

Employers must offer a free health assessment to night workers before they start night work and at regular intervals thereafter. If a night worker develops health problems connected to their night work, the employer should transfer them to suitable day work if available.

Young Worker Rules

Workers aged 15–17 (above school-leaving age but under 18) have enhanced protections:

• Maximum 8 hours per day and 40 hours per week (no opt-out available)
• 30-minute rest break if working more than 4.5 hours
• 12 hours daily rest (not 11 hours)
• 48 hours weekly rest (not 24 hours), which cannot be averaged over a fortnight
• No night work between 10pm and 6am (or 11pm and 7am in certain sectors)

These rules are absolute and cannot be waived or opted out of.

Record-Keeping Obligations

Employers must keep adequate records to demonstrate compliance with the WTR. Specifically, you must be able to show:

• That workers are not exceeding the 48-hour average (or have signed opt-outs)
• That night workers are not exceeding the 8-hour average
• That night workers have been offered health assessments
• Records of opt-out agreements

Records must be kept for 2 years from the date they were made.

Practical note: If you cannot demonstrate compliance through your records, you are in a very weak position if challenged by the HSE or at tribunal. “We don’t keep track of hours” is not a defence.

Common WTR Breaches and How to Avoid Them

Clopening Shifts

Scheduling an employee to close at night and open the next morning almost always breaches the 11-hour daily rest requirement. Build minimum gaps into your scheduling system.

Ignoring Travelling Time

If an employee’s job involves travelling to different sites, that travel time counts as working time. A mobile engineer who leaves home at 7am, travels to a site an hour away, works until 5pm and drives home is working 11 hours — not 8.

Averaging Errors

The 48-hour limit is calculated over a 17-week reference period. Some employers mistakenly apply it as a weekly limit, causing unnecessary scheduling constraints. Others forget to track it at all and discover breaches only when an employee complains.

Missing Rest Breaks in Busy Periods

During peak periods, it is tempting to push through without breaks. But the law does not include a “busy period” exemption. Workers are entitled to their 20-minute break regardless of how busy you are.

Not Recording Opt-Outs

An opt-out agreement that is not in writing is not valid. Keep signed copies and maintain a register of who has opted out and who has not.

The Cost of Non-Compliance

Breaches of the WTR can result in:

• Employment tribunal claims — workers can claim compensation for denied rest breaks or suffering detriment for asserting their rights
• HSE enforcement — improvement notices or prosecution for failing to comply with the 48-hour limit or night work provisions
• Unfair dismissal claims — if a worker is dismissed for refusing to work excessive hours or refusing to sign an opt-out
• Reputational damage — particularly in sectors facing public scrutiny over working conditions

How Technology Can Help

Managing WTR compliance manually — particularly in shift-based businesses with variable schedules — is extremely difficult. Modern scheduling and time-tracking systems can:

• Automatically flag WTR violations before rotas are published
• Calculate 17-week rolling averages in real time
• Enforce minimum rest gaps between shifts
• Track opt-out agreements and their expiry dates
• Monitor night worker hours against the 8-hour limit
• Generate compliance reports for audits and inspections

Learn more about how Assistant Manager can help you stay on the right side of the Working Time Regulations with our Employee Scheduling and Time Clock features. For a broader view of your compliance obligations, explore our Digital Checklists feature.