How to Calculate Holiday Entitlement UK: Step-by-Step Guide
A practical, step-by-step guide to calculating statutory holiday entitlement for every type of worker in the UK -- full-time, part-time, irregular hours, mid-year starters, and leavers.
Holiday entitlement calculations are one of the trickiest parts of HR and payroll. Get them wrong and you risk underpaying staff, breaching employment law, or facing costly tribunal claims. Get them right and your team gets the time off they deserve while your business stays fully compliant.
This guide walks you through how to calculate holiday entitlement in the UK for every scenario you are likely to encounter -- from straightforward full-time employees to zero-hours workers, mid-year starters, and people leaving your company. Each step includes worked examples so you can follow along with real numbers.
If you'd prefer to skip the maths entirely, our free UK holiday entitlement calculator does all of this instantly. But understanding the logic behind the numbers is essential for any HR professional or business owner managing leave.
The Basic Formula: Where 5.6 Weeks Comes From
Under the Working Time Regulations 1998, almost all workers in the UK are legally entitled to 5.6 weeks of paid annual leave per year. This is the statutory minimum -- employers can offer more, but never less.
The 5.6-week figure comes from the original EU Working Time Directive, which granted 4 weeks of leave, plus an additional 1.6 weeks added by UK legislation. Together, this gives the 5.6-week entitlement that has been law since April 2009.
For a standard full-time worker doing 5 days per week, the calculation is simple:
Full-Time Holiday Entitlement Formula
Working days per week x 5.6 = annual holiday entitlement in days
5 days x 5.6 = 28 days per year
Crucially, the statutory entitlement is capped at 28 days per year, regardless of how many days per week someone works. This cap matters for workers doing 6 or 7 days per week, as we will see below. For more detail on the underlying legislation, see our guide to Working Time Regulations in the UK.
Step 1: Calculate Full-Time Entitlement
The starting point is always the same formula: working days per week x 5.6. Here is how it works across different working patterns:
| Days Worked Per Week | Calculation | Holiday Entitlement |
|---|---|---|
| 1 day | 1 x 5.6 | 5.6 days |
| 2 days | 2 x 5.6 | 11.2 days |
| 3 days | 3 x 5.6 | 16.8 days |
| 4 days | 4 x 5.6 | 22.4 days |
| 5 days | 5 x 5.6 | 28 days |
| 6 days | 6 x 5.6 = 33.6 | 28 days (capped) |
Important: Workers doing 6 days per week would mathematically receive 33.6 days, but the statutory maximum is capped at 28 days. Employers may choose to offer the full 33.6 days contractually, but they are not legally required to exceed 28.
Step 2: Part-Time Workers (Pro-Rata Calculation)
Part-time workers receive exactly the same entitlement per week as full-time workers -- the only difference is that each "week" contains fewer days. The same formula applies: working days per week x 5.6.
This is enshrined in the Part-Time Workers (Prevention of Less Favourable Treatment) Regulations 2000. Part-time workers must not be treated less favourably than comparable full-time workers, and that includes holiday entitlement.
Worked Example: Part-Time Worker (Days-Based)
Sarah works Monday, Wednesday, and Friday each week (3 days per week).
Calculation: 3 days x 5.6 = 16.8 days of annual leave
Sarah is entitled to 16.8 days of paid holiday per year. Her employer rounds this up to 17 days as a matter of good practice.
For contracts based on hours rather than days, use this alternative formula:
Hours-Based Pro-Rata Formula
(Weekly hours / full-time weekly hours) x 28 = entitlement in days
Example: Tom works 20 hours per week. Full-time is 37.5 hours.
(20 / 37.5) x 28 = 14.93 days
Alternatively, you can calculate entitlement in hours: 20 hours x 5.6 = 112 hours of annual leave. This approach is often easier for workers with varying shift lengths, as it avoids ambiguity about what counts as a "day." Our annual leave calculator guide explains more about choosing between days and hours.
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Step 3: Irregular Hours and Zero-Hours Contracts
Workers with irregular hours or zero-hours contracts cannot use the days-per-week formula because they have no fixed working pattern. Instead, holiday accrues based on actual hours worked using the 12.07% accrual method.
Where Does 12.07% Come From?
The 12.07% figure is derived from the statutory entitlement expressed as a proportion of working time:
Deriving the 12.07% Accrual Rate
A year has 52 weeks. A worker is entitled to 5.6 weeks of leave.
That means they actually work for 52 - 5.6 = 46.4 weeks.
Holiday as a proportion of working time: 5.6 / 46.4 = 0.1207 (12.07%)
So for every hour worked, an irregular-hours worker accrues 12.07% of an hour in holiday entitlement.
Worked Example: Zero-Hours Worker
Aisha is on a zero-hours contract. Over the past 12 months, she worked a total of 820 hours.
Holiday accrued: 820 x 12.07% = 98.97 hours
If Aisha's average shift is 6 hours, this equates to approximately 16.5 days of holiday.
Most employers track this in hours rather than days to avoid confusion around varying shift lengths.
2024 Legislative Changes: From 1 January 2024, the UK Government introduced a new definition of "irregular hours workers" and "part-year workers" under the Employment Rights (Amendment, Revocation and Transitional Provision) Regulations 2023. Holiday entitlement for these workers is now calculated as 12.07% of hours worked in each pay period, and rolled-up holiday pay is once again permitted for irregular hours and part-year workers. This simplifies calculations significantly. For employers using legacy methods, transitional provisions apply -- check the latest government guidance or use our holiday entitlement calculator to ensure accuracy.
Step 4: Mid-Year Starters (Pro-Rata for Partial Years)
When an employee starts part-way through the leave year, their entitlement for that first year must be calculated on a pro-rata basis. The formula is:
Mid-Year Starter Formula
(Remaining calendar days in leave year / 365) x full annual entitlement
Worked Example: Mid-Year Starter
James starts on 1 July. The company's leave year runs from 1 January to 31 December. He works 5 days per week.
Remaining days in leave year: 1 July to 31 December = 184 days
Full annual entitlement: 28 days
Pro-rata entitlement: (184 / 365) x 28 = 14.1 days
James is entitled to 14.1 days of holiday for the remainder of the leave year. From the following January, he will receive his full 28 days.
- Rounding up is not a legal requirement, but it is considered good practice. Many employers round up to the nearest half day to avoid confusion on payslips and leave requests.
- Never round down. Rounding down could leave you providing less than the statutory minimum, which is a breach of the Working Time Regulations.
- Alternative method: Some employers use a monthly accrual approach: 28 / 12 = 2.33 days per month. James starts in July, so he has 6 months remaining: 6 x 2.33 = 14 days. This gives a similar result and is simpler to manage.
Step 5: Leavers (Calculating Final Holiday Pay)
When an employee leaves your company, you need to calculate how much holiday they have accrued up to their termination date, deduct any holiday already taken, and either pay them for any unused balance or (if allowed by their contract) deduct any holiday taken in excess.
Leaver Holiday Formula
(Months worked in leave year / 12) x annual entitlement - holiday already taken
Worked Example: Employee Leaving Mid-Year
Rachel's leave year started on 1 January. She resigns and her last day is 31 August. She works 5 days per week and has a 28-day annual entitlement. She has already taken 15 days of holiday.
Months worked: January to August = 8 months
Accrued entitlement: (8 / 12) x 28 = 18.67 days
Less holiday taken: 18.67 - 15 = 3.67 days
Rachel is owed payment in lieu of 3.67 days of untaken holiday in her final pay packet.
- Positive balance (untaken holiday): You must pay the employee for any accrued but untaken holiday. This is a legal requirement under Regulation 14 of the Working Time Regulations 1998.
- Negative balance (taken too much): If the employee has taken more holiday than they have accrued, you can deduct the overpayment from their final pay -- but only if their contract of employment expressly allows this. Without a contractual clause, you cannot make the deduction.
- Notice period: Employees continue to accrue holiday during their notice period, whether they are working it or on garden leave. Make sure your final calculation includes these days.
Getting leaver calculations wrong is one of the most common causes of employment tribunal claims related to holiday pay. If you handle many joiners and leavers, our guide on tracking employee hours legally in the UK covers the record-keeping essentials.
Bank Holidays: A Common Source of Confusion
One of the most frequently misunderstood aspects of UK holiday entitlement is the role of bank holidays. Here is the key point many employers miss:
There is no separate legal right to time off on bank holidays. Bank holidays can be included within the 28-day statutory minimum. An employer who offers "20 days annual leave plus 8 bank holidays" is giving the same total (28 days) as one who offers "28 days including bank holidays."
In practice, the two most common approaches are:
- 20 days + 8 bank holidays: The most common arrangement. Employees get 20 days to use flexibly, plus the 8 standard UK bank holidays off automatically. Total: 28 days.
- 28 days inclusive of bank holidays: Employees choose when to take all 28 days. If they want a bank holiday off, they must book it from their allowance. Common in retail, hospitality, and healthcare where bank holiday working is normal.
Bank Holidays and Part-Time Workers
This is where things get complicated. If your full-time staff get 20 days + 8 bank holidays (28 total), a part-time worker on 3 days per week must receive a fair, pro-rata equivalent. Their entitlement is 16.8 days in total -- not "12 days + all bank holidays" or some other uneven split.
Worked Example: Part-Timer and Bank Holidays
Lisa works Tuesdays, Wednesdays, and Thursdays (3 days per week). Full-time staff receive 20 days + 8 bank holidays = 28 days.
Lisa's total entitlement: 3 x 5.6 = 16.8 days
Most bank holidays fall on a Monday. Lisa doesn't work Mondays, so she wouldn't normally take bank holidays off anyway.
Fair approach: Give Lisa all 16.8 days as flexible leave. If a bank holiday does fall on one of her working days (e.g., Christmas Day on a Wednesday), she uses one of her 16.8 days for it.
The key principle: Lisa must receive the same total pro-rata entitlement as full-time colleagues, regardless of how bank holidays fall.
Common Holiday Entitlement Mistakes
Even experienced HR professionals make these errors. Avoid them to stay compliant and keep your employees happy:
1. Forgetting to pro-rata for part-time workers
A part-time worker on 3 days per week gets 16.8 days, not "a few less than full-time." Using the wrong figure is a breach of the Part-Time Workers Regulations and could lead to a discrimination claim.
2. Not capping entitlement at 28 days for 6-day workers
The maths gives 33.6 days for a 6-day-per-week worker, but the statutory maximum is 28. Going above is generous but not required. However, if you advertise "5.6 weeks" you need to be clear about the cap to avoid confusion.
3. Using calendar days instead of working days
Holiday entitlement is calculated in working days, not calendar days. If you give an employee "28 days" but count weekends, you are massively short-changing them. Always count only the days the person would normally work.
4. Not accounting for bank holidays fairly for part-timers
If a part-time worker never works Mondays, they never benefit from Monday bank holidays -- but their total entitlement must still be pro-rata equivalent. Many employers simply give part-timers all their entitlement as flexible days to keep things fair and simple.
5. Failing to pay accrued holiday on termination
When an employee leaves, any untaken accrued holiday must be paid. This is not discretionary. Failure to pay is an unlawful deduction from wages under the Employment Rights Act 1996 and can be claimed at tribunal.
Use Our Free Holiday Entitlement Calculator
Skip the maths -- get instant, accurate results for full-time, part-time, irregular hours, and mid-year starters.
Quick Reference: All Formulas in One Place
| Scenario | Formula | Example Result |
|---|---|---|
| Full-time (5 days/week) | 5 x 5.6 | 28 days |
| Part-time (3 days/week) | 3 x 5.6 | 16.8 days |
| Hours-based (20 hrs/week) | (20 / 37.5) x 28 | 14.93 days |
| Zero-hours (820 hrs worked) | 820 x 12.07% | 98.97 hours |
| Mid-year starter (184 days left) | (184 / 365) x 28 | 14.1 days |
| Leaver (8 months worked) | (8 / 12) x 28 | 18.67 days accrued |
How TimeTally Automates Holiday Entitlement
Manually calculating holiday entitlement is time-consuming and error-prone -- especially when you have a mix of full-time, part-time, and irregular-hours workers plus starters and leavers throughout the year. TimeTally handles all of this automatically.
- Automatic accrual tracking: Holiday entitlement accrues in real time based on each employee's working pattern. Full-time, part-time, and irregular-hours workers are all handled correctly from day one.
- Pro-rata calculations built in: When you add a mid-year starter, TimeTally automatically calculates their pro-rata entitlement for the remainder of the leave year. No spreadsheets required.
- Leave balance dashboard: Managers and employees can see remaining holiday balances at a glance. The dashboard shows entitlement, days taken, days booked, and days remaining in real time.
- Leaver calculations: When processing a leaver, TimeTally calculates the exact accrued-but-untaken balance and includes it in the final pay data export. No manual maths, no risk of underpayment.
- Payroll integration: Export holiday data directly to your payroll system. TimeTally integrates with popular UK payroll providers to ensure holiday pay is calculated correctly every pay period.
Whether you manage 5 employees or 500, automating holiday entitlement saves hours of HR time each month and eliminates the risk of costly calculation errors. Start your free trial and see the difference.
For teams already using spreadsheets to manage staff time off, our staff holiday tracker is a great starting point -- it gives you a centralised view of all leave across your team, with none of the manual calculation headaches.