Data Model
Semantic Data Model
Definition
The semantic data model of EN 16931 describes the meaning-based structure of an electronic core invoice independent of concrete XML syntaxes. It defines all Business Terms (BT) and Business Groups (BG) with their precise meaning, cardinality, and permitted values. Through syntax independence, the same substantive information can be expressed in both UBL and CII.
Switch to German:Semantisches Datenmodell (DE)
Related terms
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.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.Business Group (BG)A Business Group (BG) groups semantically related Business Terms (BT) of the EN 16931 standard into a logical unit. Examples include BG-4 (Seller), BG-7 (Buyer), or BG-23 (VAT breakdown). Business Groups can be nested and provide a structured organisation of the invoice data model.UBL (Universal Business Language)UBL (Universal Business Language) is an OASIS-standardised XML vocabulary for business documents, including invoices, orders, and delivery notes. UBL 2.1 is one of the two permitted syntaxes for EN 16931-compliant invoices and is used for XRechnung as well as Peppol BIS Billing 3.0, among others. UBL invoices use the namespace `urn:oasis:names:specification:ubl:schema:xsd:Invoice-2`.CII (UN/CEFACT Cross Industry Invoice)CII stands for Cross Industry Invoice and is the UN/CEFACT XML document format for invoices. It is one of the two syntaxes permitted by EN 16931 alongside UBL and forms the basis of ZUGFeRD and Factur-X. CII documents use the namespace `urn:un:unece:uncefact:data:standard:CrossIndustryInvoice:100`.