What is the CII (Cross-Industry Invoice) XML format?
CII (Cross-Industry Invoice) is an XML invoice standard developed by UN/CEFACT (United Nations Centre for Trade Facilitation and Electronic Business). The current version, D16B, is the XML syntax used in Factur-X and ZUGFeRD hybrid invoice formats. CII conforms to EN 16931, the European e-invoicing standard. It uses a different element naming structure from UBL but expresses the same invoice data model. CII is widely used in France, Germany, and where Factur-X is adopted.
How is a CII invoice document structured?
CII invoice document structure: (1) Header: ExchangedDocumentContext (customization), ExchangedDocument (type, ID, date); (2) SupplyChainTradeTransaction containing: (a) IncludedSupplyChainTradeLineItem (line items with product, quantity, price, tax); (b) ApplicableHeaderTradeAgreement (buyer-seller reference, order reference); (c) ApplicableHeaderTradeDelivery (delivery details); (d) ApplicableHeaderTradeSettlement (taxes, totals, payment terms, bank account). The structure reflects a trade documentation model rather than pure invoice structure.
Frequently Asked Questions
- Is CII or UBL better for Factur-X implementation?
- Factur-X mandates CII as the embedded XML format; there is no choice between UBL and CII for Factur-X. The Factur-X specification requires the CII D16B syntax with the applicable Factur-X profile conformance. Businesses implementing Factur-X must use CII. For invoices not using Factur-X (pure UBL for Peppol without hybrid PDF), UBL is more commonly used.
- Can a CII invoice be converted to UBL and vice versa?
- Yes, transformation stylesheets (XSLT) exist to convert between CII and UBL for EN 16931 invoices. CEN TC 434 published official mapping specifications between the two syntaxes. Conversion introduces risk of data loss if features of one format are not supported in the other. For compliance purposes, it is preferable to generate the invoice directly in the target format rather than converting from another format, as conversion introduces potential errors.