Article reference: UK-IA-EMP10

Working Time Regulations

The original 1998 Working Time Regulations have been updated numerous times.

All the regulations are in place to protect workers from being over-worked. If you are self-employed, running your own business and are free to work for different clients and customers, they do not apply to you.

A worker is someone who has a contract of employment, is paid a regular salary or wage and works for an organisation, business or individual. Trainees are also workers.

The most fundamental rule is that the maximum time a worker can work per week is 48 hours.

Work includes traveling as part of the job, working lunches and job-related training.

Working time does not include traveling between home and work, lunch breaks, evening classes or day-release courses.


A worker may agree to work more than 48 hours a week.

He or she does this by signing an opt-out agreement, which can be cancelled at any time. The agreement must state how much notice is needed to cancel the agreement, which can be up to three months but a minimum of seven days.

It is wise to place the opt-out clause in the contract of employment. It may still be cancelled by the employee at any time, but at least it is in place when the new employee starts work.

How is the average weekly working time calculated?

The number of hours worked each week should be averaged out over the reference period. This period is 17 weeks or however long a worker has been working for you if this is less than 17 weeks. You should not include paid annual leave, maternity leave, or sick pay in the calculations.

What should an employer do about a worker with a second job?

If a worker is known to have a second job, an employer should agree an opt-out with the worker if the total time worked is in excess of 48 hours a week. If the opt-out is not agreed, both employers are in breach of the law.

More generally, employers may wish to make an enquiry of their workforce about any additional employment. However, if a worker does not tell an employer about other employment and the employer has no reason to suspect that the worker has another job, it is extremely unlikely that the employer would be found not to have complied.

We advise that you put in place contracts of employment that either restrict the employee from engaging in a second job or oblige him or her to ask for permission from the employer to that extra work.

Working at night

A night worker is someone who normally works at least three hours at night. Night time is between 11pm and 6am, although workers and employers may agree to vary this.

Night workers should not work more than eight hours daily on average, not including overtime.

Special hazards

Where a night worker's work involves special hazards or heavy physical or mental strain, there is an absolute limit of eight hours on the worker's working time each day - this is not an average.

Work will involve a special hazard if it is identified:

Workers’ health and fitness for night work

If you are an employer, you must offer night workers a free health assessment before they start working, and then annually whilst working.

A health assessment can be made up of two parts: a questionnaire and a medical examination. The latter is only necessary if the employer has doubts about the worker's fitness for night work.

Employers should get help from a suitably qualified health professional when devising and assessing the questionnaire. This could be from a doctor or nurse who understands how night working might affect health.

New and expectant mothers should be given special consideration.

Special consideration should also be given to young workers' suitability for night work, taking account of their physique, maturity and experience.

As an employer it is suggested you take two steps to be sure workers are fit to work nights.

  1. You ask each worker to fill in a questionnaire that asks specific questions about his or her health that are relevant to the type of night work he or she will be doing.

  2. If you are not certain that he or she is fit for night work following the questionnaire results, you ask him or her to have a medical examination.

Health assessments must be offered before someone starts working nights. They should then be repeated on a regular basis afterwards.

What to do if a worker is unfit for night work?

If a qualified health professional advises that a night worker is suffering from health problems caused by or made worse by working at night, the worker has a right to be transferred, if possible, to suitable day work.

Time off work

A worker is entitled to a rest period of 11 uninterrupted hours between each working day and one whole day off a week. Days off can be averaged over a two-week period, meaning workers can take two days off a fortnight. Days off are taken in addition to paid annual leave.

Young workers

A young worker is someone who is above the minimum school leaving age but under 18.

A young worker is entitled to 12 uninterrupted hours in each 24-hour period in which they work. The rest may be interrupted if periods of work are split up over the day or do not last long.

A young worker's entitlement to daily rest can be reduced or excluded in exceptional circumstances only. Where this occurs, the young worker should receive compensatory rest within 3 weeks.

Young workers are entitled to two days off each week. This cannot be averaged over a two-week period.

If the nature of the job makes it unavoidable, a young worker's weekly time off can be reduced to 36 hours.

Rest breaks at work

If a worker is required to work for more than six hours at a stretch, he or she is entitled to a rest break of 20 minutes.

The break should be taken during the six-hour period and not at the beginning or end of it. The exact time the breaks are taken is up to the employer to decide.

Young workers

Different rules apply to young workers. If a young worker is required to work for more than four and a half hours at a stretch, he or she is entitled to a rest break of 30 minutes.

A young worker's entitlement to rest breaks can be changed or excluded only in exceptional circumstances.

If a young worker is working for more than one employer, the time he or she is working for each one should be added together to see if he or she is entitled to a rest break.

A young worker's entitlement to breaks can be changed or not taken in exceptional circumstances only. Where this occurs, the young worker should receive compensatory rest within 3 weeks.

Exceptions to the Working Time Regulations

There are classes of exceptions where some of the rules may not apply. These are agreements and special circumstances.


Employers and workers can agree that the night work limits, rights to rest periods and rest breaks may be varied, with the workers receiving "compensatory rest". They may also agree to extend the reference period for the working time limits up to 52 weeks.

These agreements can be made by ''collective agreement'' (between the employer and an independent trade union) or a ''workforce agreement''. If a worker has any part of their conditions determined by a collective agreement they can not be subject to a workforce agreement.

A workforce agreement is made with elected representatives of the workforce in most cases.

A workforce agreement can apply to the whole workforce or to a group of workers. To be valid, it must:

  • be in writing

  • have been circulated in draft to all workers to whom it applies together with the guidance to assist their understanding of it

  • have effect for no more than five years

  • be signed before it comes into effect either:

    • by all the representatives of the members of the workforce or group of workers

    • if there are 20 workers or fewer employed by a company, either by all representatives of a workforce or by a majority of the workforce

Special circumstances

The night work limits (including the limit for special hazards), rights to rest periods and rest breaks do not apply where:

  • a worker works far away from where he or she lives and wants to work longer hours over fewer days to complete a task more quickly

  • he or she constantly has to work in different places making it difficult to work to a set pattern

  • the work involves security or surveillance to protect property or individuals

  • the job requires round-the-clock staffing such as hospitals, residential institutions, prisons, media production companies, public utilities or industries where work cannot be interrupted

  • there are busy peak periods, such as may apply seasonally in agriculture, retail, tourism and postal services

  • an emergency occurs or something unusual or unforeseen happens. In these cases, the reference period for the weekly working time limit is extended from 17 to 26 weeks. In addition workers are entitled to "compensatory rest"

What is compensatory rest?

"Compensatory rest" is a period of rest the same length as the period of rest, or part of a period of rest, that a worker has missed.

The regulations give all workers a right to 90 hours of rest in a week. This is the total of the entitlement to daily and weekly rest periods. The exceptions allow a worker to take rest in a different pattern to that set out in the regulations.

The principle is that everyone gets his or her entitlement of 90 hours rest a week on average, although some rest may come slightly later than normal.

Unmeasured working time

The regulations, apart from the entitlement to paid annual leave, do not apply if a worker can decide how long he or she works.

A test, set out in the regulations, states that a worker falls into this category if "the duration of his working time is not measured or predetermined, or can be determined by the worker himself".

An employer needs to consider whether a worker passes this test. Workers such as senior managers, who can decide when to do their work, and how long they work, are likely to pass the test. Those without this freedom to choose are not.

Partly unmeasured working time

There is an exception for workers who have an element of their working time pre-determined, but otherwise decide how long they actually work.

The test is

  • the specific characteristics of the activity are such that, without being required o do so by the employer

  • the worker may also do work (in addition to that which is measured or pre-determined) the duration of which is not measured or pre-determined or can be determined by the worker himself

Any time spent on such additional work will not count as working time towards the weekly working time or night work limits. Simply put, additional hours that the worker chooses to do without being required to by his or her employer do not count as working time; therefore, this exception is restricted to those that have the capacity to choose how long they work. The key factor for this exception is worker choice without detriment.

Some or none of a worker's working time may meet the test. Any working time that does meet it will not count towards the 48-hour weekly working time limit or the night work limits.

This exception does not apply to:

  • working time that is paid by the hour

  • prescribed hours of work

  • situations where the worker works under close supervision

  • any time where a worker is expressly required to work, for example attendance of meetings

  • any time a worker is implicitly required to work, for example because of the loading or requirements of the job or because of possible detriment if the worker refuses


Almost all employees are legally entitled to 5.6 weeks paid holiday per year (known as statutory leave entitlement or annual leave).

Working 5 days a week

Most employees, who work a 5-day week, must receive 28 days paid annual leave per year. This is calculated by multiplying a normal week (5 days) by the annual entitlement of 5.6 weeks.

Working part-time

Part-time employees are also entitled to a minimum of 5.6 weeks of paid holiday each year, although this may amount to fewer actual days of paid holiday than a full-time employee would get.

For example, if an employee works 3 days a week, his leave is calculated by multiplying 3 by 5.6, which comes to 16.8 days of annual paid leave.

Limits on statutory leave

Statutory paid holiday entitlement is limited to 28 days. Staff working 6 days a week is entitled only to 28 days’ paid holiday and not 33.6 days (5.6 multiplied by 6).

Bank holidays

Bank or public holidays do not have to be given as paid leave. An employer can choose to include these holidays as part of an employee’s statutory annual leave.

Extra leave

An employer can choose to offer more leave than the legal minimum. They don’t have to apply all the rules that apply to statutory leave to the extra leave. For example, an employee might need to be employed for a certain amount of time before he or she become entitled to it.

The leave entitlement under the regulations is not additional to bank holidays. There is no statutory right to take bank holidays off. 

Employees must give the employer notice that they want to take leave.

Employers can set the times that employees take their leave, for example for a Christmas shutdown.

If a employee's employment ends, then he or she has a right to be paid for the leave time due and not taken.

Entitlement to leave

The entitlement to paid annual leave, including the right to compensation payments for leave not taken when you leave your job, begins on the first day of employment.

However, the employer can optionally use an accrual system whereby during the first year of employment the proportion of the leave that may actually be taken (with the employer's agreement) builds up over the year. The amount of leave that may be taken builds up monthly in advance at the rate of one-twelfth of the annual entitlement each month.

Where this calculation does not result in an exact number of days, the amount of leave that may be taken is rounded up to the next half day. Any rounded-up element is deducted from the leave remaining.

What is a week's leave?

A week's leave should allow you to be away from work for a week. It is the same as the length of time you work in a normal week.

Giving notice to take leave

Employers and employees can agree how and when to give notice of when leave is to be taken.

In the absence of an agreement, the notice period that an employee must give should be at least twice the period of the leave to be taken. An employer may refuse the employee permission to take leave requested within a period equivalent to the period of the leave.

Calculating a week's pay

The following describes the minimum a employee should be paid for their leave entitlement under the regulations.

  1. For employees paid a fixed wage or salary (fixed hours and pay)

For an employee whose normal working hours do not vary, a week's pay is the pay due for the basic hours contracted to work. Pay for overtime hours is not included unless it is guaranteed overtime, i.e. required by the contract between employee and employer.

  1. For piece work employees or employees on commission (hours constant and pay varies)

For an employee whose pay varies with the amount of work done (such as with piece work) or when a week's pay is partly made up of variable bonuses or commission directly related to that week's output, then a week's pay is the average hourly rate multiplied by normal working hours.

To calculate the hourly rate:

  • Divide weekly pay over the previous 12 week's by the number of hours worked during the same period (the pay and hours of non-compulsory overtime is excluded). Any week in which no pay was received is replaced by the week before the 12 weeks when it was, to bring the total to 12.
  • If an employee is on commission or performance-related bonuses, 12/13 of any quarterly bonus or 12/52 of any annual bonus is included. Only bonuses specifically related to a week's work should be included; general ''profit-sharing'' or other such bonuses are not included.
  • A week's pay is the total eligible pay (excluding voluntary overtime but including relevant bonuses) over the 12-week period divided by 12.
  1. For shift employees (hours and pay vary in a set pattern)

For a shift employee who works a set pattern where the hours worked and the money earned each week vary, a week's pay is the average number of hours worked each week multiplied by the average hourly rate.

For a piece work employee, the average hourly rate is calculated in the same way; i.e. add up how much has been earned over the past 12 weeks and divide it by the number of hours worked. You should not include voluntary overtime in either of these calculations.

If the employee does not work regular hours, for example, an agency employee who works different hours every week or a sales representative who gets paid commission only, then you should calculate an average by adding up all the pay for the past 12 weeks and dividing it by 12. If nothing was earned during one week, then add in the pay from the week before the 12th week to bring the total up to 12.

  1. For employees who work irregular hours (hours and pay vary)

How to avoid the problems which could arise from the regulations

The obvious first step is to set your contracts of employment in order. Your obligations are a matter of law. What is important is that you spell out the obligations of your employee to help you to comply.

Please note that the information provided on this page:

  • Does not provide a complete or authoritative statement of the law;
  • Does not constitute legal advice by Net Lawman;
  • Does not create a contractual relationship;
  • Does not form part of any other advice, whether paid or free.
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