When creating a Belgian taxpayer via POST /taxpayers, the fiscalization object requires both a tax_id_number and a vat_id_number. These are two distinct identifiers that serve different purposes and are validated independently — even though for some Belgian companies the numeric value may be the same.
In all cases, provide only the numeric digits. Do not include dots, spaces, or any country prefix.
tax_id_number — KBO/BCE Enterprise Number
This is the company registration number issued by the Belgian Crossroads Bank for Enterprises (Kruispuntbank van Ondernemingen / Banque-Carrefour des Entreprises).
- Format: 9 or 10 digits
- Pattern:
^[01]?\d{9}$ - Example:
0123456789or123456789
vat_id_number — Belgian VAT Identification Number (VATIN)
This is the VAT registration number used for tax purposes.
- Format: Exactly 10 digits
- Pattern:
^[0-9]{10}$ - Example:
0123456789
Example: Belgian fiscalization block
JSON:
{
"type": "BE",
"tax_id_number": "0123456789",
"vat_id_number": "0123456789",
"credentials": {
"type": "MYMINFIN"
}
}credentials.type must be set to MYMINFIN for Belgian taxpayers.
Common mistakes
| Mistake | What happens |
|---|---|
Including the BE prefix in vat_id_number (e.g. "BE0123456789") | Rejected — the pattern only allows digits |
| Swapping the two fields | May cause validation or transmission errors |
Including dots or spaces (e.g. "0123.456.789") | Rejected — only digits are accepted |
Providing a vat_id_number with fewer than 10 digits | Rejected — exactly 10 digits required |