BR-DE-15: Buyer reference / Leitweg-ID (BT-10) missing

What the rule requires

The buyer reference (BT-10) is optional in EN 16931 – XRechnung makes it mandatory. It tells the recipient which internal department or process the invoice belongs to.

For invoices to German public authorities this field carries the Leitweg-ID, the routing ID of the receiving office. It consists of a coarse address, a fine address and a two-digit check number separated by hyphens (e.g. 04011000-1234512345-06) and is provided by the authority, usually in the purchase order. For XRechnung invoices between companies, any reference agreed with the buyer will do, such as a cost centre or the order number.

Common causes

• The Leitweg-ID was only printed on the PDF or put into a free-text note, not into BT-10.
• The invoicing software fills BT-10 only for public authorities, but the XRechnung goes to a company.
• The reference sits in the wrong field, such as the purchase order reference (BT-13) or the remittance information (BT-83).
• The element exists but is empty or contains only spaces – this counts as missing.

What it looks like in XML

In CII syntax, BT-10 is the first element of the header trade agreement:

<ram:ApplicableHeaderTradeAgreement>
    <ram:SellerTradeParty>…</ram:SellerTradeParty>
    <ram:BuyerTradeParty>…</ram:BuyerTradeParty>
</ram:ApplicableHeaderTradeAgreement>

<ram:ApplicableHeaderTradeAgreement>
    <ram:BuyerReference>04011000-1234512345-06</ram:BuyerReference>
    <ram:SellerTradeParty>…</ram:SellerTradeParty>
    <ram:BuyerTradeParty>…</ram:BuyerTradeParty>
</ram:ApplicableHeaderTradeAgreement>

In UBL it is an element directly below Invoice:

<cbc:BuyerReference>04011000-1234512345-06</cbc:BuyerReference>

Fix in C#

With the Facturexa Creator it is a single line; the buyer reference is written to the right place – in CII and in UBL.

// Leitweg-ID of the authority, or the reference the buyer gave you
invoice.BuyerReference = "04011000-1234512345-06";

invoice.Save(xmlStream, InvoiceProfile.XRechnung);

The Leitweg-ID comes from the public authority; it cannot be derived from other invoice data.