Unique Taxpayer Reference

Detects Unique Taxpayer Reference patterns. This pattern is based on a Microsoft Purview built-in sensitive information type. Users already running Purview may prefer to enable the built-in SIT directly, or use this version as a starting point for customisation.

Type: regex
Engine: universal
Confidence: medium
Confidence justification: Medium confidence: pattern has structural constraints but corroborative keywords are recommended to reduce false positive rates.
Detection quality: Verified
Jurisdictions: uk
Frameworks: ISO 27001, ISO 27701
Data categories: pii, government-id
Scope: narrow
Risk rating: 5
Platform compatibility: Purview: Compatible, GCP DLP: Compatible, Macie: Compatible, Zscaler: Compatible, Palo Alto: Compatible, Netskope: Compatible

Pattern

\b\d{10}\b

Corroborative evidence keywords

identifier, number, ID, ID number, identification, ID card, license, permit, registration, certificate, transaction, transfer, payment, deposit, withdrawal, debit, credit

Proximity: 300 characters

Should match

1234567890 — Standard 10-digit UTR
9876543210 — Alternate UTR
0123456789 — Zero-leading UTR

Should not match

123456789 — Only 9 digits instead of 10
12345678901 — 11 digits instead of 10
123456789A — Contains a letter instead of all digits

Known false positives

Long numeric sequences in unrelated contexts (tracking numbers, serial codes) matching the Unique Taxpayer Reference format Mitigation: Use corroborative keywords and, where available, checksum validation to filter false matches.

References

U.K. Unique Taxpayer Reference Number entity definition - Microsoft Learn

Collections

European National IDs