This part of GOV.UK is being rebuilt – find out what beta means

HMRC internal manual

Statutory Payments Manual

Average Weekly Earnings (AWE) - SMP/SAP/ShPP/SPP: calculating AWE

The employees gross AWE are calculated from the total earnings paid during the relevant period divided by the number of weeks in that period. However, if the employee is not paid weekly, it may be necessary to adjust the calculation to obtain a weekly average.