Canada Bank Account Number

Detects Canada Bank Account Number patterns. This pattern is based on a Microsoft Purview built-in sensitive information type. Financial account numbers require corroborative evidence for reliable detection due to their generic numeric format.

Type

regex

Engine

universal

Confidence

low

Confidence justification

Low confidence: seven to twelve digit numbers are extremely common in non-financial contexts. Bank account keywords are essential for distinguishing financial identifiers from general numbers. Context label evidence plus explicit template/example exclusion improves precision for high-risk identifiers. Added context gating and exclusion rules improve precision and reduce incidental matches.

Detection quality

Verified

Jurisdictions

ca

Regulations

Law 25 (QC), PIPEDA

Frameworks

ISO 27001, ISO 27701, PCI-DSS, SOC 2

Data categories

pii, financial

Scope

narrow

Risk rating

5

Platform compatibility

Purview: Compatible, GCP DLP: Compatible, Macie: Compatible, Zscaler: Compatible, Palo Alto: Compatible, Netskope: Compatible

Pattern

\b\d{7,12}\b

Corroborative evidence keywords

bank account, account number, chequing, savings, banking, bank account number, savings account, [object Object], [object Object], [object Object], [object Object], checking, financial institution, Kiwibank, routing, Westpac, חשבון בנק, מספר חשבון, סניף, 口座番号 (+44 more)

Proximity: 300 characters

Should match

• 1234567 — Seven-digit Canadian bank account number
• 123456789012 — Twelve-digit Canadian bank account number
• 987654321 — Nine-digit Canadian bank account

Should not match

• 123456 — Six digits, too short for Canadian bank account
• 1234567890123 — Thirteen digits, exceeds Canadian bank account format
• sample template placeholder number 1234567890123 — Template/sample context negative — the embedded number is 13 digits, one past the maximum of 12, so the universal-engine top-level regex correctly does not match it (template gating is a Purview-tier NOT-group concern, not expressible in a bare regex)
• template example placeholder record identifier — Template/sample context should be excluded even when anchor words are present

Known false positives

• Generic numeric sequences such as reference numbers, invoice numbers, or identifiers from other domains Mitigation: Require corroborative evidence keywords within the proximity window to distinguish financial account numbers from general numeric data.
• Phone numbers, postal codes, or other structured numbers with similar digit counts Mitigation: Layer with other detection patterns to deprioritise matches that overlap with phone number or postal code formats.

References

• Canada Bank Account Number entity definition - Microsoft Learn