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HMRC internal manual

National Insurance Manual

National Insurance Numbers (NINOs): Format and Security: Use of NINO by outside bodies

The only official use of the NINO is as a reference number for HMRC and DWP but it is sometimes used by outside bodies and individuals for their own purposes. In most cases, requests to use an individual’s NINO for reasons other than the recording of NICs or claims to benefit should be refused, with an explanation that its only purpose is as a reference number for HMRC and DWP. (This content has been withheld because of exemptions in the Freedom of Information Act 2000)