Pro rata holiday entitlement explained
How pro rata annual leave works for starters and leavers, why part-time staff get scaled entitlements, and how rounding affects the final balance.
What pro rata means for leave
Pro rata is Latin for in proportion, and for holiday it means your entitlement is scaled to the slice of the year you actually work. Someone who joins in July has had access to only part of the leave year, so they accrue only part of the full allowance. The same logic applies in reverse to a leaver, who keeps the leave earned up to their final day. This tool models that by multiplying the full-year figure by the share of the year worked.
Starters, leavers and mid-year changes
A new starter accrues from their first day, so a quarter of the way through the year they hold roughly a quarter of the annual allowance. A leaver is often paid for any accrued but untaken days, or has pay deducted for days taken in advance. If your hours or entitlement change partway through the year, the cleanest approach is to calculate each period separately and add the accrued totals together. Always compare the result against your contract, since notice and probation terms can alter the picture.
Part-time and irregular hours
Part-time staff usually receive leave in proportion to the days or hours they work each week. A common method is to take the full-time allowance and scale it by the fraction of a full week worked, which is why a three-day-a-week role often lists its holiday in hours rather than whole days. Once you have that annual part-time figure, enter it as the full-year entitlement here and the pro rata maths still holds. Casual and zero-hours workers are frequently handled with a percentage-of-hours accrual instead.
Rounding and why balances look odd
Pro rata sums rarely land on whole days, so this calculator keeps two decimal places to stay accurate. Employers then apply their own rounding rule, and most round in the employee's favour or to the nearest half day. That is why a figure like 7.5 days here might appear as 8 in your HR system. Knowing the raw accrued number helps you check that any rounding is being applied consistently.