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HMRC internal manual

National Insurance Manual

Earnings Periods: No obvious regular pay interval: underlying regularity

Regulation 7(1)(b), SS(C)R 2001

If there is no obvious regular pay interval but the arrangements are that the employernormally pays the employee once in each of a succession of periods consisting of the samenumber of days, weeks or months, treat the payments as made at regular intervals.

Example 1

Some employees get their monthly pay at other than exactly monthly intervals eg on thelast Friday in the calendar month, or the first Friday in the following calendar month.The earnings period is the tax month. Occasionally, two such pay days fall within the sametax month but the employer calculates NICs separately on each month’s pay. Sometimesthe pay is for either four weeks or five weeks according to the interval since the lastpay day. Treat the payments as monthly.

Example 2

If a teacher is paid once in each of three terms in each year, the earnings period is fourmonths and the employer calculates a four monthly NIC on each term’s pay.