Validate an XRechnung

Our free check validates an XRechnung with KoSIT's official validator configuration for XRechnung 3.0.2 – format and business rules.

What is checked

• Format: is the file valid XML in the UBL or CII syntax?
• EN 16931 business rules: for example that totals and tax amounts add up and required fields are filled.
• XRechnung rules: the German additions, such as the buyer reference (the Leitweg-ID for public authorities).

What an error means for VAT

The Federal Ministry of Finance distinguishes format errors, business rule errors and content errors (letter of 15 October 2025). According to the supplementary letter of 15 October 2026:

• A format error (the file does not follow the format) means: no e-invoice.
• A file with a business rule error but no format error is, for VAT purposes, still an e-invoice in principle (para. 23). The business rule error only leads to a content error if it concerns a mandatory VAT detail (para. 22).
• The invoice is only proper if all mandatory details under §§ 14, 14a UStG are correct and complete.

Technically – for automatic processing or a public authority's portal – a file with a business rule error is not a standard-conforming e-invoice. So clear errors with the issuer; whether a correction is needed depends on which detail is affected.

How to check an invoice

1. Open the check.
2. Upload an XRechnung (XML) or a ZUGFeRD PDF.
3. You get the result with every finding, the rule it breaks and its location in the file.

The check is free, needs no account, and the file is not stored. Warnings are hints that do not affect validity.

Frequently asked questions

Which XRechnung version is checked?

The check uses KoSIT's official validator configuration for XRechnung 3.0.2.

Can I check ZUGFeRD invoices too?

Yes. For a ZUGFeRD PDF the embedded XML file is checked.

Can my software have invoices checked automatically?

Yes, through the API: your software sends invoices for validation and gets the result in machine-readable form.

Sources

• XRechnung and validator (KoSIT, German)
• § 14 UStG
• BMF letter of 15 October 2025 and of 15 October 2026

As of 19 October 2026. This guide is not tax advice.