the Buyer reference (Field BT-10 „Buyer reference“ of the European standard) EN 16931) is a mandatory field of the XInvoice, which is used when invoices are sent to authorities. Route ID accepts.
In business dealings between companies (B2B) generally does not require a lead routing ID. For VAT purposes, a placeholder such as a hyphen („-“) is sufficient. If the BT-10 field is completely missing, a business rule error exists. Validation applications typically report it as a „critical error.“ The invoice remains an e-invoice anyway, because the BMF classifies this error as immaterial for VAT purposes (BMF letter 2025, paragraphs 6b and 35a). For shipping purposes, the field remains important: without a buyer reference, validation fails. XInvoice It is incorrect and thus invalidates every invoice that is affected.
In the SAP Business One context
Where the buyer reference is located depends on the tool that the E-bill generated. In the SAP standard, it is located in the customer reference number field on the invoice. cks.eINVOICE first reads the lead number ID from a separate field in the invoice address and only then from the business partner. The E-invoice check The Versino Financial Suite checks the lead route ID not only for presence, but also for structure and verification number.
Demarcation
The buyer reference refers to the field, the leadway ID indicates the possible content of this field. The leadway ID is required by the Electronic Invoicing Regulation (ERechV) for invoices to public authorities (B2G). In B2B business, it is generally not required.
Legal status: MF Treasury letter 2025, MF Treasury FAQ as of March 2026. Module status: E-Invoicing Check Version 1.0.
E-Invoice check by Versino Financial Suite
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