Pro Rata Holiday Calculator
Calculate your annual leave entitlement in seconds. Whether you’re working part-time, started mid-year, or have a custom contract, this calculator works out your exact holiday allowance according to UK employment law.
Calculation Breakdown
How to Use This Calculator
Getting your holiday entitlement right matters. Here’s how to make the most of this calculator:
Step 1: Choose Your Employment Type
Select “Full Leave Year” if you’re calculating for a complete 12-month period. Choose “Part Year” if you started your job mid-year, left before the year ended, or want to calculate accrued leave for a specific period. When you select part year, you’ll see date fields appear where you can enter your exact employment dates.
Step 2: Define Your Working Pattern
You can calculate based on either days or hours per week. If you work a regular schedule like Monday to Friday, choose “Days per Week” and enter 5. For part-time workers with fewer days, enter the exact number. Half days count too, so if you work 2.5 days weekly, just type that in. If your contract specifies hours rather than days, switch to “Hours per Week” and enter your contracted hours.
Step 3: Add Your Contractual Allowance
Many employers offer more than the statutory minimum. If your contract states a specific number of holiday days, enter it here. Leave this blank if you want to calculate the legal minimum entitlement only. The calculator will automatically work out which gives you more days.
Step 4: Consider Bank Holidays
This is crucial. Some employers include the 8 UK bank holidays in your total allowance, whilst others give them as extra days off. Select the option that matches your contract. If you’re unsure, check your employment contract or ask your HR department.
How Pro Rata Holiday Calculation Works
The UK gives workers a legal right to 5.6 weeks of paid holiday per year. For someone working 5 days a week, that’s 28 days. But what if you work fewer days, or only worked part of the year? That’s where pro rata comes in.
Let’s say you work 3 days per week. Your calculation would be: (3 ÷ 5) × 28 = 16.8 days, which rounds up to 17 days per year.
Part-Year Calculations
Started mid-year? You’ll accrue leave based on how much of the leave year you’ve worked. The formula looks at the number of complete weeks you’ve been employed, then works out what fraction of the full entitlement you’ve earned.
Hours-Based Calculations
For workers paid by the hour or with irregular patterns, calculating in hours makes more sense. The statutory entitlement is 5.6 times your weekly hours. Someone working 20 hours per week gets 112 hours of holiday (20 × 5.6 = 112 hours).
Common Scenarios Explained
| Scenario | Working Pattern | Holiday Entitlement |
|---|---|---|
| Full-time, 5-day week | 5 days/week, 37.5 hours | 28 days (5.6 weeks) |
| Part-time, 3-day week | 3 days/week, 22.5 hours | 16.8 days (rounds to 17) |
| Part-time, 2-day week | 2 days/week, 15 hours | 11.2 days (rounds to 12) |
| Started mid-year (6 months) | 5 days/week | 14 days (half of 28) |
| Zero-hours, 12 hours/week avg | 12 hours/week | 67.2 hours annually |
Frequently Asked Questions
Common Mistakes to Avoid
Mistake 1: Rounding Down Holiday Entitlement
UK law explicitly states that part-day holiday entitlements must round up. If your calculation shows 16.3 days, you get 17 days, not 16. Employers who round down are breaking the law. This protects workers from losing holiday they’ve legitimately accrued.
Mistake 2: Forgetting to Check the Leave Year
Not all companies use the calendar year (January to December). Many use the tax year (April to April) or set their own anniversary dates. When calculating part-year entitlement, you need to know when your employer’s leave year starts and ends. Using the wrong dates can significantly affect your calculation.
Mistake 3: Mixing Up Days and Hours
Choose one method and stick with it. If you’re calculating in days, all your figures should be days. If using hours, everything should be hours. Converting between them mid-calculation often leads to errors. The calculator handles this for you by keeping everything in the same unit.
Mistake 4: Not Accounting for Accrual During Notice Periods
You continue accruing holiday during your notice period. Some people forget this and miss out on days they’re entitled to. If you’re working your notice, keep accruing until your last day of employment, and you must be paid for any unused entitlement.
Mistake 5: Assuming Bank Holidays Are Always Extra
This catches many people out. The 28-day statutory minimum can include bank holidays. Unless your contract explicitly states that bank holidays are additional, assume they’re included. Always check your employment contract to be certain.
References
- Gov.uk. “Holiday Entitlement: Workers’ Rights.” GOV.UK. Available at: https://www.gov.uk/holiday-entitlement-rights
- Gov.uk. “Calculate Your Holiday Entitlement.” GOV.UK. Available at: https://www.gov.uk/calculate-your-holiday-entitlement
- The Working Time Regulations 1998. Statutory Instrument 1998 No. 1833. UK Legislation. Available at: https://www.legislation.gov.uk/uksi/1998/1833
- ACAS. “Holidays and Holiday Pay.” Advisory, Conciliation and Arbitration Service. Available at: https://www.acas.org.uk/checking-holiday-entitlement