Data Model
Order Reference (BT-13 / BT-14)
Definition
BT-13 (buyer's order identifier) and BT-14 (seller's order identifier) allow linking an invoice to a purchase order. In public procurement, providing the order reference is often obligatory to enable automated three-way matching (order, goods receipt, invoice). Both fields are optional under EN 16931 but may be defined as mandatory by public buyers.
Switch to German:Bestellreferenz (BT-13 / BT-14) (DE)
Related terms
Business Term (BT)A Business Term (BT) is a single, semantically defined data element of the European standard EN 16931. Each Business Term has a unique number (e.g., BT-1 for the invoice number, BT-9 for the payment due date), a name, a definition, and cardinality rules. Business Terms are syntax-independent and are mapped to different XML elements in UBL and CII.EN 16931EN 16931 is the European standard that defines the semantic data model of a core invoice. It specifies the mandatory and optional fields (Business Terms), their meaning, and the validation rules that apply to all conforming electronic invoices in the EU. Nationally implemented standards such as XRechnung, ZUGFeRD (EN 16931 profile), and Factur-X must comply with this standard.Buyer Reference (BT-10)The Buyer Reference (BT-10) is an identifier specified by the buyer for internal routing and assignment of the invoice at the recipient's end. In the German B2G sector, this field is mandatory for XRechnung and is populated with the Leitweg-ID. For B2B invoices, BT-10 often serves as an order reference or cost-centre identifier and enables automated invoice processing.B2G (Business-to-Government)B2G refers to business relationships and invoicing from companies to government entities (federal, state, municipal, and public bodies). In Germany, electronic invoicing in the B2G sector has been progressively mandatory for federal authorities since 2020 and increasingly for state and municipal authorities. The required format is XRechnung or another EN 16931-compliant format.