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HMRC internal manual

National Insurance Manual

Refunds: Class 1: When NICs may be correctly paid above the annual maximum

The Department cannot refund NICs paid correctly above the annual maximum for a singleemployment. For example, a monthly paid employee paid on the first Friday in every monthmay receive 13 monthly payments in a particular tax year. Such instances will be rare,occurring once every 24 years, and the contributor gets benefit entitlement from thepayments.