Home🇬🇧 United KingdomNational Insurance Number

National Insurance Number generator (United Kingdom)

A UK National Insurance Number (NINO) is formatted AA NNNNNN A — two prefix letters, six digits, and a suffix letter A–D. These test values use a valid, non-reserved prefix.

Synthetic · not collision-guaranteed Validate a number →
PA 599267 B

Synthetic NINO with a valid, non-reserved prefix.

Format specification

IdentifierNational Insurance Number (NINO)
Country🇬🇧 United Kingdom
FormatAA NNNNNN A
Length9 characters
ChecksumNone
ExampleSH 913633 C
Safe strategy Synthetic
Data qualityVerified against sources

National Insurance Number: what each part means

AA Prefix letters. D, F, I, Q, U and V are never used, O is never the second letter, and administrative prefixes (BG, GB, KN, NK, NT, TN, ZZ) are never issued to people — these test values respect all of those rules.
NNNNNN Six-digit serial number with no embedded personal meaning.
A Suffix letter A–D. Purely administrative — it originally indicated which quarterly cycle a physical card was issued in.

Validation regex

Matches the canonical value — strip separators and uppercase first: value.replace(/[^A-Za-z0-9]/g, '').toUpperCase()

^[A-Z]{2}\d{6}[A-D]$

References

  1. www.gov.uk/hmrc-internal-manuals/national-insurance-manual/nim39110
  2. www.gov.uk/national-insurance/your-national-insurance-number

Common questions

Will these pass my validation?

Yes — they are well-formed National Insurance Number values (AA NNNNNN A) and pass standard format checks.

Could one belong to a real person?

These are synthetic values. They are format-valid but not drawn from a guaranteed reserved range, so use them only for testing.

Can I generate many at once?

Increase the count, or use the free API and CSV/JSON export for large datasets.

Validate an existing number →

For software testing only. These numbers are synthetic and must never be used for real-world identification, applications, or to impersonate anyone.