fakturai blog

Compliance & Moat

KoSIT validator for German e-invoices — what the official ACCEPT gate actually checks

Short answer: fakturai only releases an invoice when it passes the 4-layer check and receives „accept“ from the official German KoSIT validator (BMF reference). This is the authoritative bar for a technically correct EN 16931 / ZUGFeRD / Factur-X invoice.

The 4 layers (exactly as enforced in the engine Report.passed)

1. PDF/A-3b archival compliance (WeasyPrint + embedded fonts, no interpolate traps). 2. CII XSD structural validation against the EN 16931 schema. 3. Mustang EN 16931 Schematron + PDF/A (core EN 16931 rules are HARD; BR-DE/PEPPOL are ADVISORY for B2B and not part of the gate). 4. Official KoSIT validator — the decisive gate. Only „accept“ + no hard failures + pdfa_compliant passes the gate.

What fakturai checks (the KoSIT-Accept-Gate)

Same 4-layer enforcement as above. We validate format and structure to the point where the German government’s own reference engine says ACCEPTABLE. We do not validate the commercial/tax correctness of amounts, descriptions, or tax treatment — that remains the issuer’s sole responsibility (see GHOA-1671).

What fakturai does not replace (and does not promise)

Content accuracy, correct tax amounts/rates, proper GoBD archival setup, procedural documentation, bookkeeping duties, and the actual entitlement to input VAT deduction all remain 100% with the issuer and recipient. fakturai provides a format-compliant, KoSIT-accepted e-invoice file. Whether it supports Vorsteuerabzug or survives a tax audit in a specific case depends on the substantive correctness and the recipient’s processes. No guarantees (GHOA-1671).

Next step

Free e-invoice validator (ZUGFeRD / Factur-X / XRechnung) · Create e-invoices via API & MCP

Related: Mandate · Formats · Technical validation · PDF is not an e-invoice · GoBD

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