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Netherlands Detectors

Netherlands detectors cover PII patterns specific to the Dutch context. They are activated when the "nl" locale is configured.

Burgerservicenummer (BSN)

Property Value
Detector nl/bsn
PII Type NATIONAL_ID
Confidence 0.90
Validation 11-proof checksum

Detects Dutch citizen service numbers (BSN). The BSN is a 9-digit number validated using the 11-proof (elfproef) algorithm:

9*d1 + 8*d2 + 7*d3 + 6*d4 + 5*d5 + 4*d6 + 3*d7 + 2*d8 - 1*d9

The result must be divisible by 11 and must not be 0.

Examples: 123456782, 123.456.782, 123 456 782

Regulatory Context

The BSN is regulated under Wet algemene bepalingen burgerservicenummer (Wabb). Its use is restricted to government agencies, healthcare providers, and certain other authorized organizations. Severity: High.


Phone Number

Property Value
Detector nl/phone
PII Type PHONE
Confidence 0.85
Validation Dutch phone format

Detects Dutch phone numbers in mobile and landline formats:

  • Mobile: 06-XXXXXXXX, +31 6 XXXXXXXX, 0031 6 XXXXXXXX
  • Landline: 0XX-XXXXXXX, +31 XX XXXXXXX

Examples: 06-12345678, +31 20 1234567, 0031 6 12345678


Postal Code

Property Value
Detector nl/postal
PII Type POSTAL_CODE
Confidence 0.90
Validation Format + invalid letter combinations

Detects Dutch postal codes in the NNNN XX format (4 digits + 2 uppercase letters). The first digit cannot be 0, and certain letter combinations (SA, SD, SS) that are not used in the Dutch postal system are excluded.

Examples: 1234 AB, 1012WX


KvK Number (Chamber of Commerce)

Property Value
Detector nl/kvk
PII Type TAX_ID
Confidence 0.60 (bare) / 0.90 (with context)
Validation Context-boosted confidence

Detects Kamer van Koophandel (Chamber of Commerce) registration numbers. These are 8-digit numbers. Because bare 8-digit sequences are ambiguous, confidence is boosted to 0.90 when preceded by keywords like "KvK" or "Kamer van Koophandel".

Examples: KvK: 12345678, Kamer van Koophandel: 87654321


ID Document (ID Card & Passport)

Property Value
Detector nl/id_document
PII Type NATIONAL_ID / PASSPORT
Confidence 0.70
Validation Pattern matching

Detects Dutch identity card and passport numbers:

  • ID Card: 9-character alphanumeric string containing both letters and digits (e.g., SPECI2014)
  • Passport: 2 uppercase letters followed by 7 alphanumeric characters containing at least one digit

Examples: SPECI2014, NW12P4F07

Regulatory Context

Identity document numbers are protected under the GDPR and Dutch implementation laws (UAVG). Severity: High.