BR-CO-26 warning EN 16931
BR-CO-26 — seller has no VAT or tax identifier
What it means
The buyer needs to identify the seller for tax purposes, so EN 16931 expects the seller to carry a VAT identifier (BT-31) or a tax registration identifier (BT-32). Without either, the buyer cannot book input VAT or verify who issued the invoice.
What triggers it
The seller party has neither vatId nor taxRegistrationId.
How to fix it
Add the seller’s VAT ID (preferred) or a national tax registration number:
{ "seller": { "vatId": "HU12345678" } } Use the EU format (country prefix + number). A sole trader without a VAT number can use the tax registration identifier instead — but most B2B buyers expect a VAT ID.
Check your invoice now. Paste it into the free validator — it flags BR-CO-26 and every other EN 16931, Peppol and XRechnung rule, each with the fix.
Or run the same check via API:
curl -X POST https://fakturwire.com/v1/validate \
-H "authorization: Bearer $FW_KEY" \
-d '{"invoice": { ... }, "profile": "en16931"}'