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HMRC internal manual

Compliance Operational Guidance

Alternative rights of recovery (PAYE directions): primary class 1 NICs: Directions Team processes: accounting for class 1 NICs

Primary Class 1 NICs included in a decision cannot be brought into SA charge using Section 9A enquiry or ‘discovery’ procedures. The charge is accounted for using SAFE. 

Class 1A settlement

Where direction tax is to be recovered under a Class 1A settlement with the individual you should ensure that any primary NICs payable is also included.