The rule in one line
Multiply the days someone works each week by 5.6. That is their legal minimum holiday for the year, capped at 28 days.
| Days worked per week | Legal minimum per year |
|---|---|
| 1 | 5.6 days |
| 2 | 11.2 days |
| 3 | 16.8 days |
| 4 | 22.4 days |
| 5 | 28 days |
| 6 | 28 days (the cap) |
The minimum can include bank holidays. Check your contracts to see how your organisation treats them.
If you give more than the legal minimum
Many employers give full-time staff more than 28 days. If you do, part-time staff must get the same allowance pro rata, not just the legal minimum. Treating them less favourably than comparable full-time staff is unlawful unless it can be objectively justified.
Part-time allowance = full-time allowance × (days they work ÷ full-time days)
Example: full-time staff get 33 days (25 days plus 8 bank holidays) for a five-day week. Someone working three days gets 33 × 3 ÷ 5 = 19.8 days, which most employers round up to 20.
When working days are different lengths, use hours
If someone works the same hours each week but not the same hours each day, work out the allowance in days, then convert it to hours using their average working day.
- Average working day = hours per week ÷ days per week.
- Allowance in hours = allowance in days × average working day.
Example from the government’s guidance: 30 hours over four days is an average day of 7.5 hours. The minimum is 22.4 days × 7.5 = 168 hours. When they take a day off, deduct the hours they would have worked that day, which might be 6 hours on one day and 9 on another.
Rounding: up, never down
- You must never round part days down.
- In the first year of employment, round part days up to the nearest half day.
- After the first year, rounding up is optional. If you keep the part day, agree how it is taken, such as leaving early one afternoon.
Bank holidays for part-time staff
There is no legal right to have bank holidays off, but many contracts include them in the allowance. The fair approach is to pro-rate bank holidays too, rather than give part-time staff only the bank holidays that happen to fall on their working days.
Example: with 8 bank holidays a year, a three-day worker gets 8 × 3 ÷ 5 = 4.8 days added to their allowance. When a bank holiday falls on a day they normally work, they book it as leave. Someone who never works Mondays is not short-changed by Monday bank holidays.
Starters and leavers
- In the first year, holiday builds up at one twelfth of the annual amount at the start of each month.
- For someone leaving part-way through the year, pro-rate by the calendar days they were employed in the leave year, not the days they worked.
Irregular hours and part-year workers are different
For leave years starting on or after 1 April 2024, people whose hours are wholly or mostly variable, or who only work part of the year, build up holiday at 12.07% of the hours they actually work in each pay period. The figure is rounded to the nearest hour, with 30 minutes or more rounding up, and capped at 28 days a year. Their leave is held in hours rather than days, and bank holidays are not pro-rated, because the hours they work already decide what accrues. You can also pay their holiday pay as “rolled-up” holiday pay on each payslip. The days-based method above is for people with regular hours.
Leave accrued in a pay period = hours worked in the period × 12.07%, to the nearest hour
Example: someone works 68 hours in a monthly pay period. 68 × 12.07% = 8.21 hours, which rounds to 8 hours of leave for that month. In Workframe, mark the person as irregular hours on their page and record each pay period’s hours under Leave configuration; the balance, the record page and the CSV export then follow the 12.07% method.
Keep records
Since 6 April 2026, employers in Great Britain must keep adequate records of annual leave, carried-over leave and holiday pay for six years. Failing to do so is a criminal offence. A spreadsheet can work, but it has to be complete and kept up to date.
Work it out for one person
Use the free pro-rata holiday calculator to check an allowance in days and hours, including people who start or leave part-way through the year.
In Workframe, each person has a working pattern with their hours for every morning and afternoon. Set a full-time allowance and reference week once, and Workframe works out every allowance from the pattern, pro-rates bank holidays and books them automatically on working days, accrues entitlement monthly in the first year, pro-rates starters and leavers by calendar days, and caps carry-over at year end. People on irregular hours or part-year contracts accrue at 12.07% of the hours recorded for each pay period instead. Each balance has a printable page showing the working, for the six-year record. Workframe does not calculate holiday pay. See how it handles entitlement.