Working Time Regulations – 48-hour weekly working limit

The Working Time Regulations 1998 (“WTR“) protect workers from being required to work excessive hours. One of the key protections is the 48-hour weekly working limit. This means that, on average, you should not have to work more than 48 hours per week, calculated over a reference period of 17 weeks. 

The 48-hour limit is an average, not an absolute cap on any single week. So, for example, you might work 55 hours one week and 41 hours the next. The reference period can be extended from 17 weeks to 26 weeks by a valid collective or workforce agreement in certain circumstances. 

The WTR apply to the vast majority of workers in the UK, not just employees. This means that agency workers, casual workers, and many others are also covered by the 48-hour limit. 

This note covers the 48 hour weekly working limit under the WTR, but the WTR is a piece of health and safety legislation that also covers annual leave, rest breaks, rest periods and night work. 

Can you agree to work more than the 48-hour weekly limit? 

Yes, this is one of the few employment protections that you can choose to “opt out” of.  

Under the WTR, you can sign a written agreement, known as an “opt-out”, agreeing to work more than an average of 48 hours per week. This “opt-out” may be a separate agreement between you and the organisation you work for or be contained within your employment contract if you are an employee or core set of rights if you are not an employee. 

Key points about opting out:  

• It must be voluntary. You cannot be forced to opt out.  

• If you opt out, you must not be subjected to any detriment by the organisation you work for. This could be:   
  • Bullying or harassment. 
  • Having your hours reduced without good reason or consultation.  
  • Having training requests turned down without good reason. 
  • Being overlooked for promotions or development opportunities.  

• An agreement to opt out must be in writing. It should state that the worker agrees to disapply the 48 hour limit. 

• You can opt out for a specific period or indefinitely. 

• You can cancel your opt-out at any time by giving written notice to the organisation you work for:  
  • The notice period for cancelling may be specified in the opt-out agreement you have signed or your employment contract/core set of rights, but it cannot be more than three months.  
  • If no notice period is specified, the default is seven days, and you must give this amount of notice to the organisation you work for.  

• The organisation you work for must keep records of workers who have opted out. 

• Even if a worker has agreed to opt out of the limits, they cannot be required to work excessively long hours if this creates a reasonably foreseeable risk to their health and safety or the health and safety of others. The employer has a duty at common law to protect workers’ health and safety. 

Is anyone excluded from the 48-hour weekly limit? 

Yes, the main exclusions and derogations in relation to the 48-hour weekly limit include: 

• Workers in the excluded and partially excluded sectors (see below); 

• Domestic workers in private households; 

• Workers who can self-determine their working time, such as managing executives and autonomous decision-makers on the basis that they have genuine control over when and how long they work. 

• Doctors in training, who are covered by the 48-hour week, but who remain subject to an extended reference period of 26 weeks; and 

• Offshore workers who are subject to an extended reference period of 52 weeks. 

Excluded and partially excluded sectors where workers are excluded from the scope of the 48-hour week rule include: 

• Crew members on board civil aircraft; 

• Cross border railway train crew; 

• Mobile workers in maritime jobs for sea-going UK ships; 

• Workers on board sea-going fishing vessels;  

• Mobile workers on inland waterways;  

• Certain mobile road transport workers (such as HGV drivers) who are covered by the Road Transport (Working Time) Regulations; and 

• Members of the armed forces, police, and emergency services can be exempt when and where their work conflicts with the WTR. The exemption only applies when they are dealing with very serious incidents, i.e. where they are protecting life and ensuring community health and safety. 

What about young workers? 

There are more stringent daily and weekly working time limits for younger workers (those over 16 but under 18).  They must not work more than eight hours in any day or 40 hours in any week (Monday to Sunday). There are no averaging provisions for younger workers. 

What if the organisation you work for insists on you working more than 48 hours? 

If you have not signed an opt-out and you are being required to work more than an average of 48 hours per week, or if you are being pressured into signing an opt-out, there are steps you can take: 

Keep a record of your hours: Start keeping a detailed log of the hours you work each day and each week. This will be important evidence if you later decide to bring a claim. Note your start and finish times and any breaks taken. 

Raise it with the organisation you work for: In the first instance, it is worth raising the issue informally with your line manager or HR department. Point out that under the WTR, you are entitled to work no more than an average of 48 hours per week, and that you have not opted out of this limit and that it is a criminal offence to fail to comply with these limits. Explain you do not wish to opt out and would like to stick to your contracted hours. 

Make use of the organisation’s grievance procedure: If the issue is still not resolved, consider raising a formal grievance through internal procedures. This creates a record and may prompt the organisation to take the matter seriously. Put your concerns in writing and keep a copy of any correspondence.  

If the issue is still unresolved:  

If the organisation you work for has breached the 48-hour weekly working limit, or if you have suffered a detriment (such as being disciplined, demoted, or disadvantaged) because you refused to sign an opt-out or because you raised concerns about your working hours, you have legal protections. 

• Detriment claim: You can bring a claim in the Employment Tribunal if you have suffered a detriment for refusing to opt out of the 48-hour limit, for refusing to work hours that would breach the regulations, or for asserting your rights under the WTR. You do not need a minimum length of service to bring this type of claim.  Your remedy may include an award for financial losses and injury to feelings. 

• Automatic unfair dismissal: If you are an employee and are dismissed because you refused to sign an opt-out, or because you asserted your rights under the Working Time Regulations, this may amount to an automatically unfair dismissal. A claim for automatic unfair dismissal related to exercising a right under these regulations does not require the usual two years’ qualifying service. Your remedy may include an award for financial losses. 

• Health and safety enforcement: The Health and Safety Executive (or your local authority) can take enforcement action against employers who consistently require workers to exceed the 48-hour weekly limit without valid opt-outs. You can report concerns to the HSE. 

Summary  

Here are the practical steps to take if you are concerned about a breach of the WTR 

Check your contract and any opt-out: Review your employment contract and any documents you may have signed. Check whether you have signed a working time opt-out. If you have, consider whether you wish to cancel it by giving written notice.  

Record your hours: Keep a careful log of the hours you are working. This will help you establish whether your average exceeds 48 hours per week over the reference period. 

Raise the issue: Speak to your manager or use your grievance procedure to raise the matter formally.  

Get advice and consider your options: If the issue is not resolved, you may wish to bring a claim against the organisation. You will need to act quickly if you are bringing a claim in the Employment Tribunal. The time limit is currently three months less one day from the act (or last act) you are complaining about. These time limits are set to increase to six months sometime around October 2026, when new laws come into effect.  

Contact ACAS: Before you can submit an Employment Tribunal claim, you will need to engage in Early Conciliation through ACAS. Find out more about Early Conciliation and ACAS.  

This advice applies in England, Wales and Scotland. If you live in another part of the UK, the law may differ. If you are in Northern Ireland you can visit the Labour Relations Agency or call their helpline Workplace Information Service on 03300 555 300.

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