Understanding Reference Periods & Holiday Pay

Calculating Average Weekly Hours

The standard reference period is 17 weeks, though it can extend up to 52 weeks if agreed through a collective arrangement. To calculate an employee’s average hours:

• Sum all hours worked during the reference period, including overtime
• Divide by the number of weeks in the reference period

For example, if an employee works 50 hours in one week but averages fewer hours in other weeks, the overall average may remain within the 48-hour limit. ACAS guidance confirms that all working hours, including overtime, count toward this calculation.

Calculating Holiday Pay for Variable Hours

When an employee takes a week of annual leave, their pay should reflect their normal remuneration , including any regular overtime. This is mandated under UK law and supported by official guidance on calculating variable holiday pay

To calculate a week’s pay:

1. Select the appropriate reference period, usually 52 weeks
2. Exclude weeks with zero pay or no work
3. Sum total earnings over all qualifying weeks, including regular overtime
4. Divide the total by the number of qualifying weeks to find the average weekly pay

This average is then used to pay the employee for the week of leave. Regular overtime should be included if it is predictable and consistent, as confirmed in Lindsays guidance

Edge Cases & Practical Tips

Managers should be aware that:

• If the employee has worked less than 52 weeks, average over the actual weeks worked
• Exclude weeks with zero pay, but include weeks on statutory leave (unless pay is zero)
• Voluntary overtime must be included if it is regularly worked
• Fixed-hour workers with stable pay can use their standard weekly pay

How FlowRota Helps

FlowRota simplifies compliance with these calculations by:

• Tracking all shift and overtime hours over the reference period
• Summarising total and average weekly hours for managers
• Automatically calculating holiday pay based on variable hours and overtime
• Providing alerts if shifts may breach average hour limits or holiday pay rules
• Maintaining a full audit trail for compliance and reporting

By using FlowRota, managers can ensure that every employee is paid accurately, taking into account regular overtime and variable schedules, without the need for complex spreadsheets.