International Bank Account Number (IBAN)

Detects International Bank Account Numbers (IBANs) used across European and global banking systems. IBANs consist of a two-letter country code, two check digits, and up to 30 alphanumeric characters representing the domestic bank account number. This pattern matches IBANs with or without space or hyphen delimiters between digit groups.

Type: regex
Engine: boost_regex
Confidence: high
Confidence justification: The two-letter country code prefix followed by exactly two check digits provides a strong structural anchor. Combined with corroborative evidence keywords and the fixed digit-group format, false positive rates are low in most document contexts.
Detection quality: Verified
Jurisdictions: eu
Regulations: GDPR, PSD2
Frameworks: ISO 27001, ISO 27701, PCI-DSS, SOC 2
Data categories: financial, pii
Scope: narrow
Risk rating: 9
Platform compatibility: Purview: Compatible, GCP DLP: Compatible, Macie: Compatible, Zscaler: Compatible, Palo Alto: Compatible, Netskope: Unsupported

Pattern

\b[A-Z]{2}\d{2}[\s-]?[A-Z0-9]{4}(?:[\s-]?[A-Z0-9]{4}){2,7}(?:[\s-]?[A-Z0-9]{1,4})?\b

Corroborative evidence keywords

IBAN, bank account, international bank, account number, account no, BSB, routing number, sort code, SWIFT, BIC

Proximity: 300 characters

Should match

DE89 3704 0044 0532 0130 00 — German IBAN with space-separated digit groups
GB29NWBK60161331926819 — UK IBAN with no delimiters
FR76 3000 6000 0112 3456 7890 189 — French IBAN with space-separated digit groups

Should not match

DE893704 — Too short to be a valid IBAN (only 4 BBAN characters)
1234 5678 9012 3456 — Digit-only string missing the country code prefix
INVALID123456789 — Starts with more than two letters, not a valid IBAN structure

Known false positives

Strings that begin with a two-letter country code followed by two digits but are not actual IBANs (e.g. product codes, reference numbers) Mitigation: Validate the check digits using the MOD-97 algorithm defined in ISO 13616. Require corroborative evidence keywords within proximity.