Legal Working Hours & Working Time Regulations

    Legal working hours


    Workers in the UK have certain minimum statutory rights when it comes to UK working hours. These include the right to work no more than 48 hours on average per week, or to opt out of this right if they so choose, and the right to a minimum length of rest breaks. Falling foul of the law can expose employers to workplace disputes and tribunal claims.

    In this guide for employers, we explain the rules and regulations on UK legal working hours and how to comply with your obligations to support your organisation’s staffing needs while ensuring the health and safety of your workforce.


    What are the rules and regulations under the Working Time Directive?

    The law relating to UK working hours is governed by the Working Time Regulations 1998. These regulations broadly implement the Working Time Directive, a piece of EU legislation introduced in 1993. The purpose behind the Working Time Directive was to ensure that workers, in the interests of their health and safety, do not work too many hours.

    The law in the UK relating to working hours is still commonly referred to as the Working Time Directive or, alternatively, the Working Time Regulations.


    What is the maximum weekly working time under the Working Time Directive?

    Under the Working Time Directive, an individual cannot usually work more than 48 hours a week on average in the UK, although average working hours are calculated over a specific reference period, typically 17 weeks. This means that an individual can work more than 48 hours in any given week, provided the weekly average over 17 weeks is less than 48 hours.

    There are, however, limited exceptions to the 48-hour weekly average time limit, where staff can be required to work more than 48 hours a week if they work, for example:

    • in a job where 24-hour staffing is required, such as in a hospital or prison
    • in a job involving security and surveillance, such as a security guard or caretaker
    • in the armed forces or the police, or as a doctor in training
    • as a domestic servant in a private household
    • in the road, rail, sea or air transport sectors
    • as a seafarer, fisherman or worker on a vessel on inland waterways
    • where working time is not measured and the individual is in control, for example, if they are a managing executive with autonomous decision-taking powers.

    Conversely, if a worker is aged under 18, their working hours cannot be averaged out. These workers cannot work more than 40 hours in any one week.


    How many hours a day can someone work under the Working Time Directive?

    Under the Working Time Directive, there are express rules around the maximum weekly working time, but no specific limit on daily hours, provided that the average hours over the worker’s reference period equates to less than 48 hours per week. However, statutory provision is instead made under the rules and regulations for rest entitlements, including:

    • one uninterrupted 20 minute rest break during any shift of more than 6 hours, or a 30 minute rest break for under 18s in any shift of more than 4.5 hours
    • at least 11 consecutive hours rest in each 24-hour period, or 12 hours for under 18s
    • one uninterrupted period of 24 hours rest each week or 48 hours each fortnight, or 48 hours each week for under 18s.

    For those staff where the 48-hour maximum working week does not apply, such as where 24-hour staffing is required, they are still entitled to adequate rest breaks.

    Under the Working Time Directive, there are also specific rules and regulations when it comes to night workers, defined as those who, as a normal course, work at least 3 hours during the night. In most cases, a night worker should not work more than an average of 8 hours in any 24 hour period, typically calculated over a 17 week reference period. Further, if night work gives rise to workplace hazards, or any heavy physical or mental strain, the employer must ensure that any shift undertaken by a worker is not actually longer than 8 in 24 hours.


    What counts as working time under the Working Time Directive?

    Under the Working Time Directive, ‘working time’ means any period during which a person is working, is at the employer’s disposal and is carrying out their activities or duties. This means that when calculating what counts as working time, employers should include:

    • job-related training
    • time spent travelling if someone travels as part of their job, for example, as a sales rep
    • working lunches, for example, business lunches
    • time spent working abroad
    • paid overtime or unpaid overtime that someone has been asked to do
    • time spent on call at the workplace
    • any time that is treated as ‘working time’ under a contract
    • travel between home and work at the start and end of the working day, where someone does not have a fixed place of work.

    However, a working week does not include:

    • time someone spends on call away from the workplace
    • breaks when no work is done, for example, lunch breaks
    • travelling outside of normal working hours
    • unpaid overtime that someone has volunteered for, for example, staying late to finish something off
    • paid or unpaid holiday
    • travel to and from work, where someone has a fixed place of work.


    Can workers opt out of the Working Time Directive?

    Under the Working Time Directive, workers can choose to work more than 48 hours a week on average, provided they are aged over 18. This is referred to as ‘opting out’.

    A worker can agree to opt out of the rules and regulations for either a defined period or indefinitely. However, this decision must be voluntary and in writing. For an opt-out agreement to be valid, the employer must also maintain up-to-date records which:

    • identify each of the workers who have agreed that the 48-hour limit should not apply
    • set out any terms on which each worker has agreed that the limit should not apply
    • specify the number of hours worked by that individual during each reference period since the agreement came into effect, excluding
    • any period which ended more than 2 years before the most recent entry in these records
      make these records available on request to any health and safety inspector, and cooperate with any request to provide further
    • information in relation to opted-out workers.

    Workers can cancel an opt-out agreement at any time, even if this forms part of their contract of employment, provided they give the employer the prescribed notice. The length of notice will depend on what a worker agreed in writing, but should not be more than 3 months. If the written agreement is silent on the issue of notice, the notice period will be just 7 days.

    In relation to night workers, these workers cannot opt out of the night working limit under the Working Time Directive, unless this is provided for under a collective or workforce agreement. If the night working limits do not apply, the rules relating to rest breaks mean that workers must instead get compensatory breaks to make up for their extra time at work. Employers must also still follow the general rules on the maximum weekly working limit.

    Equally, due to the nature of their work or the industry sector, certain employees cannot opt out of a 48-hour week, including:

    • airline crew
    • workers on ships or boats, with the exception of seafarers, fisherman or workers on vessels on inland waterways
    • workers in the road transport industry, for example, delivery drivers, except for drivers of vehicles under 3.5 tonnes using GB Domestic drivers’ hours rules
    • other staff who travel in and operate vehicles covered by EU rules on drivers’ hours, for example, bus conductors
    • security guards on a vehicle carrying high-value goods.


    How can UK working hours be managed effectively?

    Putting in place measures to ensure that UK working hours are managed effectively is important to ensure that employers do not inadvertently fall foul of the law. Additionally, employers are under a specific statutory duty under the Working Time Directive to take all reasonable steps, in keeping with the need to protect the health and safety of workers, to ensure that workers’ hours do not exceed the maximum weekly or nightly working time.

    Any employer who fails to comply with the relevant requirements under the Working Time Directive will be guilty of an offence, liable on conviction to a fine. A worker may also lodge a complaint with the employment tribunal for an award of compensation.

    If there is a risk that staff are likely to work more than the statutory minimum permitted number of hours, there are two main options available to employers:

    • to ask staff to sign an opt-out agreement, where applicable, or
    • to reduce their weekly hours to meet the 48-hour limit.

    In most cases, employers can ask staff to opt out of the maximum number of weekly working hours, although they must make it clear that this is their choice. Equally, an employer cannot dismiss an employee, or otherwise treat them unfairly, for any refusal to do so.

    Where staff choose not to opt out, employers should ensure that some form of system is in place to correctly calculate weekly averages when it comes to working hours, to ensure that staff do not exceed their working time limit. Employers must also maintain appropriate records for a period of 2 years to prove that the time limits are being complied with. As it is an individual’s combined working hours that should not exceed 48-hours, it is important to ask staff to let the employer know if they have a second job and how many hours this involves.

    In circumstances where the need for longer hours is only occasional, employers can ask members of staff to work more than 48 hours in any given week, provided they then reduce that person’s hours over the course of the following weeks to even out their weekly average.


    What steps must be taken to manage night time workers?

    In the context of night working — and in addition to the duty under the Working Time Directive to ensure that a worker’s hours do not exceed the maximum nightly working time limits and keep records of this — employers are also under additional statutory obligations. This is because of the increased possibility of night working impacting an individual’s health.

    These additional duties include offering free health assessments to night shift workers at regular intervals, as well as keeping records of the assessments that have been offered, accepted and refused. The employer is also under a duty to undertake a suitable and sufficient workplace risk assessment to identify any potential hazards arising from night working. If any risks are identified as a result of this assessment, the employer must take measures to eliminate or control these risks or, alternatively, offer those affected day time work instead.


    Legal working hours FAQs

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    Legal disclaimer

    The matters contained in this article are intended to be for general information purposes only. This article does not constitute legal advice, nor is it a complete or authoritative statement of the law, and should not be treated as such. Whilst every effort is made to ensure that the information is correct, no warranty, express or implied, is given as to its accuracy and no liability is accepted for any error or omission. Before acting on any of the information contained herein, expert legal advice should be sought.



    Gill Laing is a qualified Legal Researcher & Analyst with niche specialisms in Law, Tax, Human Resources, Immigration & Employment Law.

    Gill is a Multiple Business Owner and the Managing Director of Prof Services - a Marketing & Content Agency for the Professional Services Sector.

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