How to Calculate Holiday Entitlement for Part-Time Workers (UK)
Part-time staff get the same 5.6 weeks' holiday as full-timers, pro-rata. Here's how to calculate it correctly — with worked examples for fixed days, varying hours and bank holidays.
Part-time workers are entitled to the same 5.6 weeks of paid holiday as full-time staff — just pro-rated to the days they work. The simplest way to work it out is to multiply the days they work each week by 5.6. A 3-day-a-week employee gets 3 × 5.6 = 16.8 days a year.
Getting this wrong — usually by under-counting part-timers or mishandling bank holidays — is a common source of underpaid-holiday disputes. Here's how to do it properly, with worked examples.
The basic rule
Every worker in the UK is entitled to a minimum of 5.6 weeks of paid annual leave. For someone working 5 days a week, that's the familiar 28 days (5 × 5.6). The "weeks" framing is the key: entitlement is measured in weeks worked, then converted to days.
So for anyone on fixed days each week, the formula is simply:
Days worked per week × 5.6 = annual holiday entitlement (in days)
Worked examples (fixed days)
| Days worked per week | Calculation | Annual entitlement |
|---|---|---|
| 5 days | 5 × 5.6 | 28 days |
| 4 days | 4 × 5.6 | 22.4 days |
| 3 days | 3 × 5.6 | 16.8 days |
| 2 days | 2 × 5.6 | 11.2 days |
| 1 day | 1 × 5.6 | 5.6 days |
You can round entitlement up (e.g. 16.8 → 17), but never down — rounding down would take an employee below the statutory minimum. Many employers keep the fractional figure and let staff take a half-day to use it exactly.
What about bank holidays?
This is where part-time calculations most often go wrong. There are 8 bank holidays in England & Wales, and most of them fall on a Monday. If a part-timer doesn't work Mondays, treating bank holidays as "free" days off would quietly short-change them relative to a full-timer.
The fair fix is to include bank holidays in the total entitlement and pro-rate the whole thing. Give the part-timer their full pro-rata 5.6 weeks (inclusive of bank holidays), and let them draw down that pot whenever they take time off — including on any bank holiday they'd normally have worked. This avoids the Monday-worker / Friday-worker unfairness entirely.
Whichever approach you use, it must match what the employment contract says.
Workers with no fixed days or varying hours
If someone's hours change week to week (casual, bank, or zero-hours staff), you can't use "days per week." Instead, holiday accrues based on time actually worked.
Historically many employers used the 12.07% method (because 5.6 weeks is 12.07% of the 46.4 working weeks in a year, so each hour worked earns 0.1207 hours of holiday). But following the Supreme Court ruling in Harpur Trust v Brazel (2022), you cannot simply cap a permanent worker's holiday at 12.07% if it would give them less than the full 5.6 weeks. For irregular-hours and part-year workers, recent rules also allow an accrual method based on 12.07% of hours worked in a pay period — but the safest position is to check current GOV.UK guidance for your worker's exact arrangement, as this area has changed. For the post-2024 rules in full, see our guide to holiday for irregular-hours and zero-hours workers.
A note on holiday pay vs. holiday entitlement
Two different things, often confused:
- Entitlement = how many days/hours off they get (this guide).
- Pay = how much they're paid for those days — which for anyone with overtime, commission or variable hours must be based on a 52-week average, not just basic salary. See our separate guide on holiday pay including overtime.
Doing it automatically
Pro-rating every part-timer by hand — and keeping bank holidays fair across people who work different days — is exactly the kind of admin that produces quiet errors.
Coverboard calculates pro-rata entitlement automatically from each employee's working pattern, handles bank holidays consistently across part-time and full-time staff by region, and tracks balances so nobody is accidentally taken below their statutory minimum.
This guide is general information, not legal advice. For decisions about a specific employee or working pattern, consult an employment law professional.