Reference

E-Invoicing Glossary

Plain-English definitions of the acronyms, standards, and compliance models that come up across e-invoicing mandates worldwide. 29 terms, grouped by topic.

Foundations

E-Invoicing#: Issuing, exchanging, and storing invoices in a structured electronic format (typically XML) that allows automated processing and tax-authority validation, in place of paper or unstructured PDF invoices.
B2B#: Business-to-Business — invoices issued by one VAT-registered entity to another. Most national e-invoicing mandates start with B2B before extending to B2C and B2G.
B2G#: Business-to-Government — invoices issued to public-sector buyers. B2G is often the first scope to be mandated (e.g. EU Directive 2014/55/EU) before broader rollouts.
B2C#: Business-to-Consumer — invoices issued to private individuals. Simplified e-invoice formats (e.g. ZATCA Simplified Invoice) often apply for B2C with reduced reporting cadence.
VAT in the Digital Age(ViDA)#: The European Commission's reform package modernising EU VAT rules, including mandatory cross-border e-invoicing and digital reporting requirements from July 2030 (postponed from 2028).

Compliance Models

Continuous Transaction Controls(CTC)#: Real-time or near-real-time tax-authority visibility into invoices, typically requiring submission before or shortly after issuance. Subdivided into clearance, reporting, and decentralised CTC exchange models.
Clearance Model#: A CTC variant where the tax authority must approve (clear) an invoice before it becomes legally valid and can be issued to the buyer. Examples: ZATCA Phase 2 in Saudi Arabia, SAT in Mexico.
Post-Audit Model#: The traditional model — invoices are exchanged directly between buyer and seller and only inspected by tax authorities afterwards, typically through periodic VAT returns or random audits.
Real-Time Reporting#: Invoices are issued normally between parties but a structured copy must be transmitted to the tax authority within a short window (e.g. 24 hours). Used by ZATCA for B2C and by Hungary (NAV).
Decentralised CTC Exchange(DCTCE)#: A five-corner model where invoices flow buyer ↔ seller via certified access service providers (ASPs), with a parallel report to the tax authority. Adopted by France, Belgium, and the UAE PINT AE framework.
Five-Corner Model#: Peppol-derived architecture where two access service providers exchange documents between buyer and seller corners, with the tax authority as the fifth corner receiving reporting in parallel.

Standards & Formats

Universal Business Language(UBL)#: An OASIS open-standard XML library for business documents (invoices, credit notes, orders, etc.). UBL 2.1 is the dominant invoice schema worldwide and the basis for Peppol BIS Billing 3.0.
Peppol(PEPPOL)#: The Pan-European Public Procurement OnLine framework — an interoperability network letting any participant exchange standardised business documents through accredited access points. Governed by OpenPeppol.
Peppol International Invoice(PINT)#: A globally consistent baseline invoice specification built on UBL, designed for country-specific customisation. UAE (PINT AE) and several Asia-Pacific jurisdictions have adopted PINT-derived specs.
PINT AE#: The UAE-specific specialisation of PINT used by the Federal Tax Authority's e-invoicing programme. Adds local fields (e.g. AED currency, Arabic language, FTA reporting identifiers) on top of the PINT core.
EN 16931#: The European semantic invoice standard mandated for B2G invoicing in the EU under Directive 2014/55/EU. Defines business terms, syntax bindings (UBL, CII), and a core invoice model.
FATOORA XML#: Saudi Arabia's UBL 2.1 invoice format extended with ZATCA-specific elements (UUID, cryptographic stamp, QR code, prior-invoice hash). Two variants: Standard (B2B) and Simplified (B2C).
SAF-T#: Standard Audit File for Tax — an OECD-defined XML format for exporting accounting data to tax authorities. Used in Portugal, France, Lithuania, Poland, and others as a complement or precursor to live e-invoicing.

Authorities & Platforms

ZATCA#: Zakat, Tax and Customs Authority — Saudi Arabia's tax authority responsible for the FATOORA e-invoicing programme and Phase 2 integration with VAT-registered taxpayers.
FATOORA#: ZATCA's e-invoicing integration platform. Taxpayers in scope (by revenue wave) must connect their billing systems to FATOORA for clearance (B2B) or reporting (B2C).
FTA#: United Arab Emirates Federal Tax Authority — operator of the UAE e-invoicing programme under Ministerial Decisions 243/244 of 2025. Adopts a decentralised five-corner Peppol-based model.
NBR (Bahrain)#: National Bureau for Revenue — Bahrain's VAT authority, currently designing the country's phased B2B e-invoicing mandate (expected 2026 rollout).
OTA (Oman)#: Oman Tax Authority — runs the Oman e-invoicing programme, with a sandbox live since February 2026 and mandatory rollout for top 100 VAT-registered companies in August 2026.

Technical Building Blocks

XSD#: XML Schema Definition — a W3C standard that constrains the structure and data types of an XML document. UBL invoices validate against XSDs maintained by OASIS.
Schematron#: An ISO XML validation language (ISO/IEC 19757-3) used to express business rules that go beyond what XSD can check — e.g. cross-field dependencies, country-specific calculations, conditional fields.
XSLT#: Extensible Stylesheet Language Transformations — a W3C language for transforming XML. Schematron rules are commonly compiled to XSLT 2.0 for execution.
XAdES#: XML Advanced Electronic Signatures — an ETSI standard for cryptographically signing XML documents. Used by ZATCA Phase 2 to bind a stamp to each invoice.
UUID#: Universally Unique Identifier — a 128-bit identifier assigned to each invoice in many regimes (e.g. FATOORA) so it can be referenced globally without coordination between issuers.
QR Code (Invoice)#: A 2-D barcode embedded in e-invoices encoding key fields (seller, total, VAT amount, timestamp, sometimes signature). ZATCA mandates QR codes on both Standard and Simplified invoices.