UBL-SR-12
EN 16931-1 layer: en16931
Checked against Peppol BIS Billing 3.0 2026.5
What does UBL-SR-12 mean? Seller VAT identifier shall occur maximum once
Why did my invoice fail UBL-SR-12?
The Seller VAT identifier (BT-31), the seller's value added tax identifier, may occur at most once. In UBL it is the cac:AccountingSupplierParty/cac:Party/cac:PartyTaxScheme entry whose cac:TaxScheme/cbc:ID is 'VAT', and only one VAT-scheme entry is permitted for the seller.
Official rule text
Seller VAT identifier shall occur maximum once
Common causes
- The seller is registered for VAT in several countries and each is emitted as a PartyTaxScheme with TaxScheme ID 'VAT'.
- A VAT number is duplicated across two cac:PartyTaxScheme blocks.
- The tax representative's VAT ID is mistakenly added under the seller party with scheme 'VAT'.
How do I fix it?
Keep a single VAT entry: <cac:PartyTaxScheme><cbc:CompanyID>DE123456789</cbc:CompanyID><cac:TaxScheme><cbc:ID>VAT</cbc:ID></cac:TaxScheme></cac:PartyTaxScheme>; put any non-VAT registration under a separate scheme (e.g. 'TAX').
Related rules
UBL-SR-01 · UBL-SR-02 · UBL-SR-03 · UBL-SR-04 · UBL-SR-05 · UBL-SR-06 · UBL-SR-07 · UBL-SR-08
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