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HMRC internal manual

National Insurance Manual

NIM10012 - Aggregation of Earnings: Calculating NICs: Earnings Periods: General

Regulation 6, SS(C)R 2001

The earnings period over which NICs are calculated is dependant on the type of NICspayable for each employment. Regulation 6 of the Social Security (Contributions)Regulations 2001 provides for the earnings period to be adopted in given circumstances.