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UK Pro-Rata Tool

UK Holiday Accrual Calculator (Pro Rata)

Leaving a job or starting mid-year? Calculate exactly how many days of holiday you have built up.
Statutory minimum is 28 days for full-time. Include bank holidays if your contract does.
When does your company holiday year begin? (Or your joining date if you are a new starter).
Your last day of employment, or today's date.
End date must be after start date.
Total Accrued Holiday
0.0
Days Earned
Next Step: Don't forget to subtract the number of days you have already taken this year to find your final balance.
Note: This tool uses the standard UK HR calculation method (Days worked / 365 * Annual Allowance) to provide a precise pro-rata figure.

Why you need a holiday accrual calculator

If you work a full calendar year at a company, calculating your holiday is easy—you simply get your full contractual allowance (usually 28 days or more). However, if you join a company part-way through the year or hand in your notice to leave, you are only entitled to a portion of that leave. This is where a holiday accrual calculator becomes essential.

Perfect for new starters and leavers

In the UK, holiday entitlement builds up (accrues) smoothly over the course of the year. During your first year of a new job, the law states that your leave accrues at a rate of one-twelfth (1/12) of your total annual entitlement per month. For leavers, HR departments use a daily pro-rata calculation to ensure you get paid exactly what you have earned up to your final working day.

How to calculate pro rata holiday entitlement

The standard formula used by UK businesses to calculate accrued holiday days is surprisingly simple once you break it down:

Our calculator automates this math, factoring in the exact calendar days between your selected dates to give you a highly accurate figure.

Handling payment in lieu of untaken holiday

If you are leaving your job, the number produced by this calculator is critical. Once you know your accrued holiday, you must subtract any days you have already taken off this year. If the resulting number is positive, you have untaken holiday.

By law, your employer must pay you for this untaken accrued statutory leave in your final payslip. This is known as "Payment in lieu of holiday". Conversely, if you have taken more holiday than you have accrued by your leave date, your employer is legally allowed to deduct the overpaid amount from your final wage.

Frequently Asked Questions

How do you calculate accrued holiday pay for leavers?

You calculate the proportion of the leave year the employee has worked (e.g., days worked divided by 365), and multiply that by their total annual holiday entitlement. Then, subtract any holiday days they have already taken.

What is payment in lieu of holiday?

Payment in lieu of holiday is the money an employer must pay an employee for any accrued statutory annual leave that they have not taken by the time they leave the company.

Do I accrue bank holidays while on maternity leave?

Yes. In the UK, your statutory annual leave (including bank holidays, if they are part of your contractual entitlement) continues to accrue exactly as normal while you are on statutory maternity, paternity, or adoption leave.