BR-DE-15: buyer reference missing
XRechnung requires every invoice to carry a buyer reference (business term BT-10). For German public-sector buyers this is the Leitweg-ID, the routing ID that tells the recipient's system where the invoice belongs.
What the validator reports
BR-DE-15: Das Element "Buyer reference" (BT-10) muss übermittelt werden.This is the message our validator returns for an invoice with this problem. The text is the official rule text.
The official XRechnung rule texts are published in German, so the message is in German.
How to fix it
Ask the buyer for their Leitweg-ID or reference and put it in the buyer reference field. If a private buyer has no Leitweg-ID, agree another reference with them, such as an order or customer number: the rule only checks that a value is present, but the buyer's system may need it to route the invoice.
In the XML (UBL)
<cbc:BuyerReference>04011000-12345-34</cbc:BuyerReference>With the Valinvo API (JSON)
"buyerReference": "04011000-12345-34"Related rules
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