UK NINO Validator
National Insurance Number format validation only.
Format: 2 letters + 6 digits + 1 suffix letter (A–D). Spaces optional.
Normalized
Issues
Disclaimer
Syntax only. This tool does not verify HMRC assignment, entitlement, or whether a number is currently in use.
No generator. We do not produce realistic NI numbers — enter your own value to validate format.
Privacy: Processed locally in your browser; nothing is uploaded.
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