Working days in the UK: how to count them

What counts as a working day?

A working day is a day the employee is normally contracted to work. For most UK office roles that's Monday to Friday, but plenty of teams work Tuesday to Saturday, four-day weeks, or compressed hours. What matters is the pattern in the employee's contract — not the calendar.

Weekends and public (bank) holidays that fall on a working day are not working days. If someone doesn't normally work Fridays, a Friday bank holiday isn't "given back" to them — they weren't going to work it anyway.

The basic formula

For a leave request from a start date to an end date:

1. Walk every calendar day between the two dates (inclusive).
2. Skip days that aren't in the employee's working pattern.
3. Skip UK bank holidays for the employee's region.
4. Subtract 0.5 for each half-day at the start or end.

That's it. Everything else is edge cases.

UK bank holidays by region

Bank holidays are not the same across the UK. England & Wales, Scotland and Northern Ireland each have their own set:

• England & Wales: 8 permanent bank holidays including Easter Monday and the two May bank holidays.
• Scotland: 2nd January and St Andrew's Day instead of Easter Monday, plus an earlier August bank holiday.
• Northern Ireland: All England & Wales dates plus St Patrick's Day and the Battle of the Boyne (12 July).

If a bank holiday falls on a weekend, the UK government moves it to the next working day (a "substitute day"). Boxing Day 2026 lands on a Saturday, so the substitute is Monday 28 December 2026.

Worked example: full week off

Someone works Monday to Friday and books off Mon 25 May to Fri 29 May 2026. Monday 25 May is the Spring bank holiday. That's 5 calendar weekdays minus 1 bank holiday = 4 working days.

Worked example: part-time pattern

Someone works Mon / Tue / Wed only, and books off Mon 1 June to Fri 5 June 2026. The Thursday and Friday aren't working days for them, so they use 3 working days, not 5.

Worked example: half-days

A full-time employee books Mon 6 July afternoon to Wed 8 July morning. That's 3 working days with a half-day off each end, so 0.5 + 1 + 0.5 = 2 working days.

Pro-rating for mid-year joiners

If your leave year runs Jan–Dec and someone joins on 1 July, they get roughly half the full-year entitlement — rounded up to the nearest half-day so nobody gets rounded down. The same logic applies in reverse for leavers.

Formula: full_year × (days_employed_in_leave_year ÷ days_in_leave_year), rounded up to 0.5.

Statutory minimum

UK full-time employees are entitled to a statutory minimum of 5.6 weeks of paid leave per year — 28 days for a 5-day week. Bank holidays can be included in that 28, or added on top; the contract decides. Part-time workers get 5.6 weeks of their normal working week (e.g. a 3-day-a-week employee gets 16.8 days).

Common mistakes

• Counting a Saturday bank holiday twice — the calendar date and the substitute day are the same holiday.
• Forgetting that Scottish and Northern Irish staff have different bank holidays.
• Rounding pro-rated entitlement down instead of up.
• Deducting a bank holiday from a part-timer who doesn't work that weekday.

Let Leavo do the counting

Every working-day rule above is baked into Leavo. Pick a start and end date on the request form and the correct number of working days appears immediately — with the right bank holidays for the employee's region, their working pattern and any half-days. Pro-rating for joiners and leavers is automatic.