How to calculate annual leave in the UK?

Use our annual leave calculator to work out how much time off your employees are entitled to, and learn more about holiday carry over and pay.

We all love a holiday, don’t we? Whether it’s at a fancy seaside resort, a relaxing city break, or a staycation, there’s nothing better than being able to turn work mode off and take some well-earned rest.

But for UK business owners, thinking about holidays also involves calculating annual leave for employees. When there’s a constant barrage of questions from sun-starved employees, this can get a little tricky, particularly around the topic of holiday carryover.

Thankfully though, help is at hand with this in-depth guide, and our annual leave calculator for UK businesses.

In this short piece, we run through how to calculate annual leave entitlement and explain everything you need to know about employee holiday rights in the UK.

How does holiday entitlement work?

Before we look at any annual leave calculations, let’s review how holiday entitlement works.

How much holiday you receive is normally set out in your employment contract.

Most UK workers with fixed-hour contracts are entitled to a minimum of 5.6 weeks’ annual leave per year, capped at 28 days paid, unless the company offers an additional amount. It is important to note that bank and public holidays CAN be included in this amount.

UK workers on non-fixed or irregular hours are entitled to a percentage of annual leave for every hour they work, and there’s a specific way of working out holiday pay for zero hour contracts.

How do we calculate annual leave entitlement in the UK?

You can use our simple, free annual leave calculator below to determine the amount of entitlement an employee would get for the number of days they work.

You can use it as both a full-time and part-time leave calculator.

How do we calculate annual leave for fixed hours staff?

For a basic leave calculation for a UK allowance, you simply multiply the number of days worked on average each week by 5.6.

For example, if someone you employ works a five-day week, they would be entitled to 28 days’ annual leave a year.

5 days x 5.6 weeks = 28 days

How do we calculate annual leave for part-time staff?

If you're dealing with a part-time worker in the UK, the same calculation applies.

This means that regardless of how many days worked, they will still be entitled to 5.6 weeks, multiplied by the number of days worked per week.

For example, if someone you employ works just three days a week, you would multiply this number by 5.6.

3 days x 5.6 weeks = 16.8 days

How do we calculate annual leave for irregular hours staff?

If a staff member doesn’t have a set number of working hours each week, such as casual and zero-hours workers, your annual leave calculation will be done slightly differently.

Here you have two options: workers can either acquire a percentage of annual leave against their hours worked or accrue holiday pay instead.

For example, if you can potentially work the full year, you would accrue 12.07% annual leave for every hour you work.

The calculation for this method is as follows:

Calculating annual leave for your staff

Get the guide

When should annual leave be paid?

Workers should be paid for annual leave when they either:

• Take their annual leave - in other words, they go on holiday;

• When they leave your employment; or

• If they’re an irregular worker and are paid through rolled-up holiday pay.

What are the holiday carry over rules?

Employees must take all four weeks of EU statutory leave during their leave year. If they don’t, these will be lost. The 1.6 weeks (or eight days if you work full-time) that the UK adds to this statutory leave may be carried over if agreed with the employer. However, it’s not an automatic right.

What are the exceptions to these rules?

There are exceptions to this legislation. If your employee has holiday carry over due to being on statutory leave (such as maternity, paternity, adoption, shared parental, carer’s, or neonatal care leave), then they can carry over the entire amount over.

However, if the carry over is due to sickness, they can carry only up to 20 days over.

As an employer, you can decide to offer more than the statutory leave, and, in this case, more leave can be carried over. This should be stated on all your employment contracts and accompanying employee handbooks.

Should you allow carry over?

If you’re a business owner, you will need to decide whether you want to allow unused holiday days to be carried over.

Many employers worry about the costs associated with allowing carry over, especially with the 2025 increases to the National Living Wage and Employer National Insurance, and the impact that it will have on the business.

However, it’s important to remember that statutory holiday entitlement is there for a reason, and employees should be encouraged to take time off.

With an estimated 40% of UK employees using their full holiday entitlement, it may be a nice option to offer your employees. But, of course, the choice is up to you.

How to automate annual leave and holiday management?

If manually calculating annual leave and responding to holiday and pay queries is getting tiresome then you might want to consider automating this process with payroll and HR software.

Payroll software can do the heavy lifting, but we’re so much more than just a simple payroll solution. Not only does it automatically calculate holiday entitlement for all regular workers, but also acts as a holiday management solution for UK businesses. Employees can request leave through their employee portals, which managers then approve and keep tabs on upcoming holiday dates using our holiday and remote working calendar. Plus, when leave is taken, payslips update in real-time.

Want to experience the future of payroll?

Book a demo