What it means
When the VAT number of a party starts with uppercase NL after surrounding whitespace is removed, it must have the form NL123456789B12: the capital letters NL, nine digits, the capital letter B and two digits. This covers the seller's VAT number (BT-31), the buyer's VAT number (BT-48) and the VAT number of the seller's tax representative (BT-63). Dots, spaces inside the number, dashes, a lowercase b or a missing B part make it fail. If the number does not start with uppercase NL, this rule does not check it. It runs in Peppol BIS Billing 3.0.
Why it matters
Peppol BIS Billing 3.0 requires VAT numbers beginning with uppercase NL to use the Dutch VAT number format.
How to fix it
Correct the VAT number so it reads NL, nine digits, B and two digits, for example NL123456789B01, with capital letters and no dots, spaces or dashes. Copy it from the relevant party's VAT registration letter from the Belastingdienst. If you build the XML yourself, it is cbc:CompanyID inside cac:PartyTaxScheme, where the tax scheme is VAT.
Once the file is corrected, check it again for free: Validate a Peppol BIS invoice
Or fix the invoice in a form and download the corrected file, for 1 credit: Fix a rejected e-invoice
The rule as published
Read the rule on the publisher's site
Where this rule applies
| Rule set | Version |
|---|---|
| Peppol BIS Billing 3.0 (invoice) | 2026.5 |
| Peppol BIS Billing 3.0 (credit note) | 2026.5 |
Check your file
Drop your e-invoice to see whether PEPPOL-COMMON-R056-2 still fails, and which other rules do.