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HMRC internal manual

Decisions and appeals for National Insurance Contributions and Statutory Payments

Wording of National Insurance contributions decisions in aggregation cases: Introduction

NIM10000 provides guidance about aggregation of earnings.

Disputes can arise about whether earnings should be aggregated. If disputes cannot be resolved a decision should be issued which includes a Class 1 National Insurance contributions (NICs) liability and a Class 1 NICs paid decision. The guidance

If you have not done so already, in a covering letter, explain why the decision has been issued and how the NICs were calculated. Do not include anything about aggregation of earnings in the wording of the decision.

In some disputes about aggregation of earnings, if more than one employer is liable to pay NICs, see DANSP35700 for guidance about how to word such decisions.