Summarise with AI
The 17-week working time period
The Working Time Regulations cap working time at 48 hours a week on average, normally over 17 weeks. The averaging is what people get wrong in both directions: a 60-hour week during a busy period is not automatically unlawful, and a steady run of 50-hour weeks quietly is.
Some sectors extend the period by collective or workforce agreement. Whatever period applies, the employer must keep records adequate to show the limit is being complied with — which means being able to reconstruct someone's actual hours across the whole window months later.
The 52-week holiday pay period
Where hours or pay vary, holiday pay is an average of weekly pay across the 52 weeks before the leave. Three rules govern it:
- Take the 52 weeks immediately before the holiday begins
- Discard any week with no pay at all, substituting the next earlier paid week — looking back up to 104 weeks
- If fewer than 52 paid weeks exist, use however many there are
The second rule is the one most often skipped, and it matters most for anyone returning from long-term sickness or a period of no work. Our holiday pay guide works through the calculation.
Why the records matter
Both reference periods are backward-looking averages, which means both depend entirely on having accurate historical data. A 17-week hours average and a 52-week pay average are trivial if hours are recorded as they happen, and close to unrecoverable if they are reconstructed from a spreadsheet a year later.
That is the practical reason clocked hours matter more than a rota here: the rota records what was planned, and both averages are calculated on what was actually worked. The same averaging drives the leaving balance in final pay when someone leaves.
