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HMRC internal manual

Decisions and appeals for National Insurance Contributions and Statutory Payments

Notices of decisions: How to serve a notice of decision

Regulation 4 of the Social Security Contributions (Decisions and Appeals) Regulations 1999 (SI 1999 no 1027)

A notice of decision must be served by post. You cannot serve the notice by any other means of communication, for example, e-mail or fax.

Serving by post can include delivery by hand if this is ever considered necessary.