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HMRC internal manual

National Insurance Manual

Earnings Periods: Earnings paid at regular intervals: Occasional changes in pay interval

Regulations 7(1)(a) & 2(a), SS(C)R 2001

Occasional changes in the pay interval do not change the earnings period. If on anisolated occasion an employer pays an employee on a day other than their regular pay day,treat the payment as made on the regular pay day and within the earnings period in whichthat day falls. See also NIM08700 et seq. and particularlyNIM080720 if the payment spans different tax years.