EN 16931 is the semantic foundation of e-invoicing in Europe. The standard defines what information an e-invoice must contain, regardless of technical format. Country-specific implementations (CIUS) refine this model; PINT extends the scope beyond Europe.

EN 16931 is the European standard for electronic invoicing, developed by CEN (the European standardisation body) on behalf of the European Commission. The standard is legally anchored in EU Directive 2014/55/EU and describes the semantic model: which data an e-invoice must or may contain, such as supplier, buyer, invoice number, invoice date, amounts and VAT rates.

It is exclusively about content, not technical format. Every e-invoice considered valid in Europe must comply with this model.

On 13 March 2026, CEN formally approved the revised version EN 16931-1:2026. This version replaces EN 16931-1:2017+A1:2019 and is not backward-compatible.

Instances complying with the new standard use urn:cen.eu:en16931:2026 in BT-24 (Specification identifier). The old identifier urn:cen.eu:en16931:2017 remains valid only for instances conforming to the previous version.

The revision broadens the scope from a primarily B2G-focused standard to full B2B support and aligns with the ViDA package for automated VAT reporting.

New Business Terms include: BT-166 (Invoice issue time), BT-167 (VAT accounting currency exchange rate), BT-197/198 (Delivery note reference at document and line level), BT-188/132 (Invoice line purchase and sales order references), BT-211/212 (Item attribute code and value with unit of measure, including CO2 reporting), and BT-215/216 (payment service provider identifiers).

• BT-10 Buyer reference: from 1..1 to 0..n, with optional scheme identifier (UNTDID 1153).
• BT-29 Seller identifier and BT-46 Buyer identifier: from 1..n to 0..n, with mandatory (1..1) scheme identifier from ISO/IEC 6523.
• BT-60 Payee identifier also receives a mandatory scheme identifier.
• New business rules BR-69 through BR-76 mandate scheme identifiers and regulate payment account verification for intra-community transactions.

The standard explicitly confirms that an invoice may reference multiple purchase orders and multiple deliveries, both at document level and at line level. Document-level and line-level identifiers are mutually exclusive (BR-CO-28 through BR-CO-46).

EN 16931-1:2026 restricts BT-125 (Attached document) to: application/pdf, image/png, image/jpeg, text/csv, application/vnd.openxmlformats-officedocument.spreadsheetml.sheet (XLSX), application/vnd.oasis.opendocument.spreadsheet (ODS) and application/xml.

Note -- future, not currently valid for BIS Billing V3. application/xml as an attachment MIME type belongs to EN 16931-1:2026 and a future Peppol version (possibly BIS Billing 4.0). The current Peppol BIS Billing 3.0 production validation (BR-CL-24) does not allow application/xml; see the article on BIS Billing V3.

Annex A.4 removes, among others, BR-CO-17 (simple VAT calculation formula), BR-S-10/Z-10/IG-10/IP-10 (prohibited exemption reason for certain VAT rates) and BR-O-2 through BR-O-14 (old restrictions around "Not subject to VAT"). Existing validators must disable or replace these rules.

Peppol BIS Billing V3 will be updated to support the new standard; a new Peppol version is expected in 2026-2027, possibly as BIS Billing 4.0. Until then, the existing restriction of one OrderReference per invoice applies to BIS instances. National CIUS variants (NLCIUS, XRechnung, ebInterface) follow at their own pace; NLCIUS is coordinated for the Netherlands via NEN.

EN 16931 has two officially recognised syntax bindings:

Both syntaxes express the same semantic information in a different XML structure.

Countries may refine the European model via a CIUS (Core Invoice Usage Specification). A CIUS adds country-specific rules but may never conflict with the underlying EN 16931 model. An invoice that complies with a CIUS automatically complies with EN 16931.

PINT (Peppol International Invoice) extends the reach of EN 16931 beyond Europe. It is a separate profile based on EN 16931, with region-specific variants:

PINT is the successor to BIS Billing for international Peppol invoicing. The eConnect PSB supports PINT Singapore (PINT-SG) and PINT-SK as production-ready variants. The other PINT variants are on the roadmap. See the article on PINT for the current status per region.

EN 16931  (semantic model)
    |
    +-- Syntax bindings
    |     +-- UBL 2.1
    |     +-- CII (UN/CEFACT)
    |
    +-- Profiles
    |     +-- Peppol BIS Billing 3.0
    |     +-- PINT (international)
    |           +-- PINT EU
    |           +-- PINT A-NZ
    |           +-- ...
    |
    +-- CIUS (country-specific)
          +-- NLCIUS (Netherlands)
          +-- XRechnung (Germany)
          +-- Svefaktura (Sweden)
          +-- ...

The EN 16931 series includes, alongside Part 1, CEN/TS 16931-2 (syntax list), CEN/TS 16931-3-1 through -3-4 (syntax bindings UBL 2.1 and UN/CEFACT CII), CEN/TR 16931-4 (transmission interoperability) and CEN/TS 16931-7 (CIUS development). New in 2026: CEN/TS 16931-8 (e-receipt and simplified e-invoice), CEN/TR 16931-9 (VAT reporting and gap analysis) and FprCEN/TR 16931-10 (extension to B2B).