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UK NINO Validator

Online UK National Insurance Number (NINO) validator. Verify DWP constraints.

How does NINO validation work?

Validation checks if the NINO has exactly 9 characters (two prefix letters, six central digits, and a final suffix A, B, C, or D).

The validator checks strict DWP constraints: first letter cannot be D, F, I, Q, U, V, or O; second letter cannot be D, F, I, Q, U, V, or O; and specific geographic/test prefixes (like BG, GB, NK, ZZ) are marked as invalid.

Validation FAQ