Holiday entitlement calculator: how to work out annual leave in the UK

Since 6 April 2026, UK employers must keep detailed holiday and holiday pay records for at least 6 years, with the new Fair Work Agency empowered to treat gaps as a criminal offence (ACAS, updated June 2026). With reforms also reshaping how irregular-hours and part-year workers accrue leave, using a holiday entitlement calculator and understanding the underlying formulas has never mattered more for staying compliant.

Whether you're working out holiday entitlement manually, checking a part-time holiday calculator, or calculating leave for zero-hours workers, getting the sums right protects both your business and your people.

What is statutory holiday entitlement in the UK?

Almost all workers are entitled to paid annual leave, regardless of whether they work full-time, part-time or on a casual basis.

What is the minimum annual leave entitlement?

Under the Working Time Regulations 1998, workers are generally entitled to:

• 5.6 weeks' paid holiday per year

• Up to 28 days' leave for someone working five days a week

This statutory entitlement may include bank holidays, depending on the terms of the employment contract.

💡 Good to know: Some organisations also introduce holiday purchase schemes, allowing employees to buy extra annual leave in exchange for a salary sacrifice arrangement. 

What happens to holiday entitlement when an employee leaves partway through the year?

Employers can choose to:

• Include bank holidays within the statutory 28-day entitlement; or

• Offer bank holidays in addition to statutory annual leave.

This should be clearly set out in employment contracts and company policies.

How do you work out holiday entitlement?

Calculating annual leave for full-time employees

A full-time employee working five days per week will generally receive:

• 5.6 weeks × 5 working days

• = 28 days' paid holiday per year

An annual leave entitlement calculator can help employers quickly confirm an employee's entitlement and manage leave more efficiently.

Calculating annual leave for part-time staff

When calculating annual leave for part-time staff, employers should ensure they know a part-time employee hours per week, as these are key to determining the correct amount of leave. Holiday entitlement should then be based on the number of days or hours worked each week.

📌 Example:

• An employee working three days per week:

• 5.6 weeks × 3 days

• = 16.8 days' holiday per year

A part-time holiday calculator can make these calculations easier and help ensure consistency.

Do bank holidays count towards holiday pay for irregular-hours workers?

Using the 12.07% method

The 12.07% method is commonly used to calculate holiday accrual for irregular-hours and casual workers.

The formula is:

Hours worked × 12.07% = holiday entitlement accrued

📌 Example:

• 100 hours worked

• 100 × 12.07%

• = 12.07 hours of holiday accrued

Using a holiday accrual calculator can simplify these calculations and help employers keep accurate records.

⚠️ Warning: The 12.07% accrual method should only be used where it is appropriate under current legislation, such as for eligible irregular-hours or part-year workers. It should not be applied to all employees.  

Some employers instead choose rolled-up holiday pay, where holiday pay is paid as a 12.07% uplift alongside wages rather than when leave is taken.

Calculating leave for zero-hours workers

Employers should ensure they calculate zero-hour contract holiday pay fairly and accurately.

Holiday entitlement for zero hours contract holiday pay is usually based on the hours they actually work, rather than a fixed number of days.

This means employers may need to regularly review:

• Hours worked

• Holiday accrued

• Holiday taken

• Remaining entitlement

How to use a holiday entitlement calculator

A holiday calculator can help employers quickly determine annual leave based on an employee's working pattern. For businesses with a mix of full-time, part-time and irregular-hours workers, a pro rata annual leave calculator can be particularly useful for ensuring leave is calculated fairly and consistently. 

How is holiday pay calculated?

Holiday entitlement and holiday pay are closely linked, but they are not always calculated in the same way.

How to manually calculate holiday pay

A holiday allowance calculator can make the process easier, but employers should understand the underlying principles.

Holiday pay should generally reflect what an employee would normally earn, which may include:

• Regular overtime payments

• Certain commission payments

• Regular allowances 

What if an employee is off sick?

Calculating holiday pay when off sick can be more complex.

Employees continue to accrue statutory annual leave while on sick leave and may be able to:

• Take holiday while off sick; or

• Carry forward certain untaken leave in some circumstances.

👉 To note: Employees who become ill during booked annual leave may be able to reschedule their holiday and take sick leave instead, provided they follow the employer's sickness reporting procedures. 

How can employers improve holiday management? 

As businesses grow, manually managing annual leave can become increasingly difficult. 

Keep accurate records

Maintaining accurate records can help employers:

• Track holiday balances

• Manage leaves and absences

• Reduce the risk of errors

Accurate records are particularly important when employers need to calculate holiday entitlement based on hours worked.

Create a clear holiday policy

A well-defined holiday policy should explain:

• How holiday entitlement is calculated

• How employees request leave

• Whether bank holidays are included

• Rules around carrying leave forward

• How compassionate leave requests are handled

💡 Good to know: Some employers offer unlimited holiday as an employee benefit. While there is no legal limit on the amount of contractual annual leave an employer can provide, employees must still receive at least the statutory minimum entitlement and businesses should ensure their policy is applied consistently and fairly. 

⚠️ Warning: Since 6 April 2026, employers must keep records of holiday taken, holiday carried over, holiday pay and any payments in lieu of holiday for at least 6 years. The Fair Work Agency can treat a failure to evidence this as a criminal offence (ACAS, updated 3 June 2026).

Can technology make holiday calculations easier?

Managing annual leave manually can be time-consuming, particularly for growing businesses with different working patterns and leave arrangements. 

Simplifying holiday calculations

Digital tools can help employers:

• Track leave balances automatically

• Reduce administrative workloads

• Improve visibility across teams

• Keep employee records organised

• Support more accurate leave calculations

An annual leave calculator can also help employers quickly check entitlements and reduce the risk of errors.

Giving managers more time to support employees

Calculating holiday entitlement manually can be challenging, particularly for businesses with part-time, irregular-hours or growing teams. Payroll software can help automate leave calculations, keep employee records up to date and provide greater visibility over annual leave balances, reducing administrative work and the risk of errors. 

With less time spent managing annual leave manually, employers can dedicate more time to supporting employees and driving business growth. Interested in learning more? Request a free demo and discover how digital payroll solutions can help simplify holiday management and make annual leave calculations quicker, easier and more accurate. 

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