Pro-rata holiday calculator
Part-time, starting partway through the year, or leaving? Find out how much of your annual holiday allowance you get, and how much you have earned so far.
How the proration works
Your first year’s allowance is your annual allowance multiplied by the share of the leave year left from your start date. That share counts the rest of your first month by days, plus every full month after it, out of 12. Starting on 16 March with 25 days a year: 16 of March’s 31 days remain (0.52 of a month), plus 9 full months, gives 9.52 months, and 25 × 9.52 ÷ 12 ≈ 19.8 days.
Results are rounded down to a tenth of a day, so the calculator never promises holiday you haven’t earned. Some employers round to the nearest half or whole day instead. Your contract has the final word.
Leaving partway through the year
A leaver’s allowance works the same way, from the start of the leave year to the leaving date. Leaving on 30 September with 25 days a year and a January leave year: 9 months, so 25 × 9 ÷ 12 = 18.75 days. Holiday you have earned but not taken is usually paid in your final pay; holiday taken beyond it may be deducted, if your contract says so.
Part-time workers
Holiday for a part-time week is the full-time allowance scaled to the days you work: full-time days × your days a week ÷ 5. In the UK, everyone who works a fixed number of days is entitled to 5.6 weeks of paid holiday a year: 28 days for a five-day week, and 5.6 × 3 = 16.8 days for three days a week, which is what this calculator gives for a 28-day full-time allowance at 3 days. The statutory 28 days can include bank holidays, and is capped at 28.
Leave years that don’t start in January
Many employers run the leave year from April to March, or from the anniversary of the company’s founding. The calculation is the same, counted from the first month of your leave year: joining on 1 October with an April leave year leaves 6 months, so 25 × 6 ÷ 12 = 12.5 days.
Gradual or immediate accrual
With gradual accrual, one twelfth of your allowance is earned at the end of each month; with immediate accrual, the whole year’s (prorated) allowance is available from day one. Both reach the same total by 31 December. Read more in pro-rata holiday allowance explained.
Keep track all year
For a full-time week and a leave year that starts in January, Clockflux uses exactly this calculation. Enter your allowance and start date once, mark your days off in the calendar, and it keeps your earned, used and available days up to date. See holiday allowance.