XRechnung Validator

KoSIT (Koordinierungsstelle für IT-Standards) is the German coordination office for IT standards. The KoSIT validator is the official tool for checking XRechnung and other e-invoice formats against the EN 16931 European standard. It performs both XML schema validation and Schematron business rule checks.

Using the official KoSIT validator ensures your invoices will be accepted by German public authorities and other recipients requiring XRechnung compliance. Our free online validator uses the same official validation engine.

XRechnung is the German national standard for electronic invoicing, mandatory for invoices to public sector entities since November 2020. It is based on the European EN 16931 standard and uses XML format (UBL or CII syntax). XRechnung ensures interoperability and compliance with EU Directive 2014/55/EU.

Learn more about the XRechnung Standard and XRechnung Field Reference.

EN 16931 is the European standard for the semantic data model of electronic invoices. It defines the core elements required for cross-border e-invoicing within the EU. XRechnung implements EN 16931 with additional German-specific rules (CIUS). Validation against EN 16931 ensures your invoices meet the minimum requirements for European e-invoicing.

Learn more about EN 16931 →

When validating XRechnung invoices, you may encounter various error codes. Here are the most common issues:

• BR-DE-1: Leitweg-ID is required for German public sector invoices
• BR-CO-10: Sum of line amounts must equal the invoice total
• BR-DE-15: Buyer reference (BT-10) is mandatory
• BR-S-08: Tax category codes must be valid

View all KoSIT error codes and solutions →

KoSIT validation outputs schema checks (XML structure) and Schematron rules (business rules). Understanding both helps you fix issues quickly and ensure the invoice is accepted by recipients.

• Schema errors usually mean the XML is malformed or elements are in the wrong place.
• Business rule (Schematron) errors point to missing mandatory fields or invalid values (codes, totals, dates).
• Each finding contains a rule code (e.g., BR-DE-1) and the affected field (BT/BG reference when available).
• After fixing, re-validate until the invoice is fully compliant.