ShiftLens

The 48-hour week and opting out

Workers shouldn't work more than 48 hours a week on average, normally worked out over 17 weeks. Workers aged 18 or over can choose to opt out. The opt-out must be voluntary and in writing.

ShiftLens provides guidance, not legal advice. This guide is a summary for England, Scotland and Wales. Some rules have exceptions, and contracts or workforce agreements can change some of the details. For advice on your situation, contact Acas or an employment solicitor.

How the average works

The limit is an average, not a cap on any single week. A worker can do 55 hours one week and 40 the next. The average is normally taken over any 17-week period, so it rolls forward week by week. For someone who has worked for you for less than 17 weeks, it's the time since they started.

Overtime counts. Breaks when no work is done, such as lunch breaks, don't. Days of annual leave, sick leave and parental leave are taken out, and made up with the days worked straight after the period. A collective or workforce agreement can stretch the period to up to 52 weeks.

Someone with more than one job should still average no more than 48 hours a week across all of them.

Opting out

  • Only workers aged 18 or over can opt out.
  • The opt-out must be voluntary and in writing.
  • The employer must keep a record that the worker has opted out.
  • The worker can cancel it by giving at least 7 days' notice in writing, or a longer notice period if one was agreed, which can't be more than 3 months.

An opt-out covers the 48-hour average only. It doesn't change rest, breaks, or the night work limit.

Under-18s

Workers aged 16 and 17 can't opt out. They have stricter, fixed limits instead: 8 hours a day and 40 hours a week. See working hours for under-18s.

How ShiftLens checks this

Most rotas cover 1 to 4 weeks, which is only part of the 17-week period. So ShiftLens shows each week over 48 hours, and what the average would be if the pattern carried on, as an early warning rather than a finding. For someone who started during the rota, the rota covers their whole period so far, so it's marked “Check this”.

A rota can't show opt-outs, leave, sickness, other jobs or hours outside its dates. You can tell ShiftLens about opt-outs in “Add details”.

Check your rota for this

ShiftLens totals each person's weekly hours and shows what the average would be if the pattern carried on. It's free, there's no sign-up, and your rota never leaves your browser.

Check your rota

Sources

gov.uk: maximum weekly working hours; gov.uk: calculating your working hours; gov.uk: opting out; Working Time Regulations 1998, regulation 4; regulation 5; regulation 23