Work out pro-rata annual leave for any part-time pattern, in days and in hours. The round-up rule and the 28-day statutory cap are built in, and you can share the result as a link.
Book Time Off Editorial Team·Updated May 2026·Free, no sign-up
Full-time reference
Statutory minimum is 28 days for a 5-day week.
Part-time pattern
Two half-days count as one day. Use 4.5 for four full days plus a half-day.
Show result in hours
Pro-rata holiday entitlement
16.8days a year
A 3-day-a-week worker gets 5.6 weeks of leave, the same as a full-timer, just spread over fewer working days.
Part-time holiday is worked out pro-rata: multiply the part-timer's days per week by the full-time weeks of leave. On the statutory minimum that is 5.6 weeks, so a 3-day-a-week worker gets 16.8 days a year. Where the maths gives a fraction, round up, never down.
How this calculator works
UK law gives every worker 5.6 weeks of paid holiday a year, whether they work full time or part time. Part-time entitlement is the same number of weeks as a full-timer, simply expressed across fewer working days. The calculation has two equivalent forms, and this tool uses the one that also works when the employer offers more than the statutory minimum.
For the statutory minimum this is just 5.6 × part-time days per week.
Start with the full-time allowance
Take the annual leave a full-time employee on the same contract receives, in days. The UK statutory minimum is 28 days for a five-day week. Many employers offer more, for example 25 days plus eight bank holidays.
Convert it to weeks of leave
Divide the full-time allowance by the full-time days per week. 28 days over a 5-day week is 5.6 weeks. A 33-day allowance over a 5-day week is 6.6 weeks. This weeks figure is what part-time and full-time staff share equally.
Apply the part-time pattern
Multiply the weeks of leave by the number of days the part-timer works each week. At 5.6 weeks, a 3-day-a-week worker gets 16.8 days; a 4-day-a-week worker gets 22.4 days; someone on four full days plus a half-day gets 25.2 days.
Round up if you track whole days
If you keep the leave register in whole days rather than fractions, the result must be rounded up, never down, because a part-time worker cannot end up worse off proportionally than a full-timer. 19.6 days becomes 20. Tracking in hours sidesteps this entirely.
Worked examples
Each card loads its inputs into the calculator above. They assume the statutory 28-day full-time allowance over a five-day week unless stated.
Bank holidays can leave part-timers short. Bank holidays cluster on Mondays and Fridays. A worker who never works Mondays would miss most of them. If full-time staff get bank holidays as paid leave, give part-time staff a pro-rata share of those days added to their pot, so they are not treated less favourably.
Changing hours mid-year. If someone moves from full-time to part-time partway through the leave year, recalculate from the date the change happens. Leave already accrued at the old pattern is not reduced. Our part-time holiday entitlement guide walks through a worked split-year example.
Track part-timers in hours. Recording leave in hours rather than days removes the rounding question completely and makes half-day patterns simple. Multiply the pro-rata days by the length of a normal working day to get the hours figure shown above.
What this calculator does not do: it does not handle irregular-hours or part-year (term-time) workers, who accrue holiday at 12.07% of hours worked under the post-2024 rules, and it does not pro-rata for a mid-year start or leaving date. For irregular hours see our zero-hours holiday guide, for a leaver see our leaver holiday pay calculator, or use the official GOV.UK calculator and the ACAS helpline for unusual contracts.
Frequently asked questions
How do you calculate holiday entitlement for part-time workers in the UK?
Multiply the number of days the employee works each week by the full-time weeks of leave. For statutory minimum leave that is 5.6 weeks, so a 3-day-a-week worker is entitled to 5.6 x 3 = 16.8 days a year. If the full-time allowance is more than the statutory minimum, divide it by full-time days per week first to get the weeks figure, then multiply by the part-time days.
How many holiday days does a part-time worker get on 4 days a week?
On the UK statutory minimum, a 4-day-a-week worker is entitled to 22.4 days of paid holiday a year (4 x 5.6). If the employer offers an enhanced full-time allowance, the figure is higher: a 33-day full-time allowance over a 5-day week gives a 4-day-a-week worker 26.4 days.
Do you round part-time holiday entitlement up or down?
Round up, never down. Part-time workers cannot be treated less favourably than full-time workers, so if the calculation produces a fraction and you track leave in whole days, the figure must be rounded up. A result of 19.6 days becomes 20 days. Many employers avoid the issue entirely by tracking part-time leave in hours.
Are part-time workers entitled to bank holidays?
There is no automatic right to bank holidays off, paid or otherwise, for any worker. If full-time staff get bank holidays as paid leave, part-time staff must receive a pro-rata equivalent so they are not treated less favourably, especially where bank holidays fall on days they do not normally work. A common approach is to add a pro-rata share of the bank holidays to the part-timer's annual pot.
Is part-time holiday entitlement capped at 28 days?
The statutory minimum is capped at 28 days for the full-time equivalent, so someone working six or seven days a week still only has a statutory minimum of 28 days. Part-time workers are almost always below that cap. If an employer offers an enhanced contractual allowance above the statutory minimum, the pro-rata of that larger figure applies and the 28-day cap does not.
How do you work out part-time holiday in hours?
Take the pro-rata entitlement in days and multiply by the length of a normal working day in hours. A 3-day-a-week worker entitled to 16.8 days, working 7.5-hour days, has 126 hours of holiday a year. Tracking in hours is the cleanest method for part-time and irregular patterns because it removes the rounding problem.
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Sources
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What it confirms
ACAS · Checking holiday entitlement
3 days a week = 16.8 days (3 x 5.6); statutory cap of 28 days
GOV.UK · Holiday entitlement
5.6 weeks statutory minimum; pro-rata for part-time workers
GOV.UK · Calculate holiday entitlement
Official methodology for days and hours patterns
Working Time Regulations 1998
The statutory 5.6 weeks paid annual leave entitlement
Part-time Workers Regulations 2000
Part-timers cannot be treated less favourably; basis of the round-up rule
Built by the Book Time Off editorial team. We make leave management software for UK SMEs and build practical tools and guides on UK employment law, holiday entitlement and HR best practice. The calculation is checked against current GOV.UK and ACAS guidance and updated as the rules change.
This is not legal advice. This calculator is for general guidance on UK holiday entitlement and does not replace professional advice for your specific situation. For complex contracts or a dispute, contact the ACAS helpline.
One tracker for full-time, part-time, and everyone in between
Set the right annual allowance for every team member, 28 days for full-timers, 16.8 for someone on three days a week, whatever fits the contract. Calendar and wallchart views, days remaining at a glance, UK bank holidays loaded automatically from the GOV.UK feed.