1. Hours and limits

Staff who regularly work at least 3 hours during the ‘night period’ are night workers.

The night period is 11pm to 6am, unless the worker and employer agree a different night period.

If they do, it must be 7 hours long and include midnight to 5am. It must be agreed in writing.

Staff may also be night workers if there’s a collective agreement (eg trade union agreement) that states their work is night work.

National Minimum Wage

The National Minimum Wage applies to night workers but there isn’t a higher night working rate.

A sleep shift in the night period (eg care worker) counts as working hours if the worker is both:

  • on call
  • in the workplace

Workers on a sleep shift can be paid a flat rate for the shift, but their average pay must not fall below the National Minimum Wage.

Limits on working hours for night workers

Additional rules apply to night workers on top of the rules on maximum weekly working hours and rest breaks.

Night workers must not work more than an average of 8 hours in a 24-hour period.

The average is usually calculated over 17 weeks, but it can be over a longer period of up to 52 weeks if the workers and the employer agree, eg by collective agreement.

Regular overtime is included in the average, but not occasional overtime.

Workers can’t opt out of the limit.

Workers aged 16 or 17

Staff aged 16 or 17 can’t work between midnight and 4am.

They usually can’t work between 10pm and 6am (this can be changed to not working between 11pm and 7am, by contract) but there are exceptions if they work in:

  • agriculture
  • cultural, sporting, artistic or advertising activities
  • a hospital
  • a hotel or catering
  • retail
  • post or newspaper delivery

In exceptional circumstances they can work at night if there’s no adult to do the work and they’re needed to either:

  • handle a sudden increase in demand
  • maintain the continuity of a service or production, eg filming

The employer must give the young person a rest period of the same length as the extended shift.

There are other restrictions on employing young people.

Special hazards and mental or physical strain

Night workers who deal with special hazards or whose work involves mental or physical strain can’t work longer than 8 hours in any 24-hour period.

A risk assessment must be carried out to identify special hazards and work involving mental or physical strain.

The hazards and strains may also be set out in collective or workforce agreements.

What employers must do

Employers must keep records of night workers’ working hours to show they aren’t exceeding the limits.

The records must be kept for at least 2 years.

Contact Acas for more information.

You can’t discriminate against a worker if they don’t want to work nights.