KoSIT (Koordinierungsstelle für IT-Standards) is Germany's federal coordination office for IT standards. It maintains the official validation engine used to check XRechnung and EN 16931 e-invoices for compliance.

Why does Invoice Navigator use KoSIT?

Invoice Navigator uses KoSIT for revalidation after remediation. After our engine fixes structural errors, KoSIT independently confirms the result is compliant — the same check German public authorities perform. This two-stage approach ensures genuine compliance.

Is KoSIT validation mandatory?

For invoices submitted to German public sector entities, KoSIT validation is the standard compliance check. While not legally mandatory for the sender, passing KoSIT validation is effectively required for invoice acceptance.

How current is KoSIT validation?

Invoice Navigator tracks KoSIT rule set releases and updates within days of new publications. The current rule set version is shown in our system status and referenced in every Evidence Pack.

Can I run KoSIT validation independently?

KoSIT publishes their validator as open-source software. However, setting it up requires Java, configuration management, and rule set maintenance. Invoice Navigator handles this as part of the integrated pipeline — validate, remediate, and revalidate in one API call.

Learn · tools

What is KoSIT?

KoSIT (Koordinierungsstelle für IT-Standards) is the German federal coordination office for IT standards that maintains the official validation engine for XRechnung and EN 16931 e-invoices.

Quick facts

Full NameKoordinierungsstelle für IT-Standards

Maintained ByGerman Federal IT Council (IT-Planungsrat)

ValidatesXRechnung, EN 16931, Peppol BIS

Used InGerman public sector e-invoicing

IN IntegrationRevalidation after remediation

How KoSIT works

KoSIT publishes validation configurations (rule sets) that define exactly which checks an XRechnung invoice must pass. The validator engine processes an invoice XML against these rules and produces a structured report indicating pass/fail for each rule. Invoice Navigator integrates KoSIT natively: after our remediation engine fixes structural errors, the corrected invoice runs through KoSIT for independent verification. This ensures our fixes actually resolve the compliance issues — not just our own validation, but the same validation German authorities use.

Why KoSIT matters

Using KoSIT for revalidation means Invoice Navigator's compliance results match what the German government sees. When you submit an invoice that passed our KoSIT revalidation, you can be confident it will also pass on the receiving end. The Evidence Pack documents this KoSIT result, giving auditors verifiable proof of compliance.

How to get started

You don't need to set up KoSIT yourself — Invoice Navigator handles it. When you validate an invoice through our API or Validator tool, KoSIT revalidation is included automatically. The result appears in your Evidence Pack.

XRechnung
Germany's official e-invoice format
E-Invoice Remediation
How auto-fix works
Evidence Packs
Audit-ready compliance certificates
EN 16931
The European e-invoice standard

Frequently Asked Questions

What is KoSIT?: KoSIT (Koordinierungsstelle für IT-Standards) is Germany's federal coordination office for IT standards. It maintains the official validation engine used to check XRechnung and EN 16931 e-invoices for compliance.
Why does Invoice Navigator use KoSIT?: Invoice Navigator uses KoSIT for revalidation after remediation. After our engine fixes structural errors, KoSIT independently confirms the result is compliant — the same check German public authorities perform. This two-stage approach ensures genuine compliance.
Is KoSIT validation mandatory?: For invoices submitted to German public sector entities, KoSIT validation is the standard compliance check. While not legally mandatory for the sender, passing KoSIT validation is effectively required for invoice acceptance.
How current is KoSIT validation?: Invoice Navigator tracks KoSIT rule set releases and updates within days of new publications. The current rule set version is shown in our system status and referenced in every Evidence Pack.
Can I run KoSIT validation independently?: KoSIT publishes their validator as open-source software. However, setting it up requires Java, configuration management, and rule set maintenance. Invoice Navigator handles this as part of the integrated pipeline — validate, remediate, and revalidate in one API call.

Learn

E-Invoicing Deadlines What is E-Invoice Remediation?

Glossary

Evidence Pack

Errors

E-Invoice Error Library

Answers

How do you validate an e-invoice?

Blog

XRechnung BR-DE Validation Errors: The Complete Troubleshooting Guide for Developers EN 16931 Validation: The Complete Rule Map (955 Rules Explained)

Validators

XRechnung Validator

Have an e-invoice that came back rejected? Check it here.

Check the rejected invoice

Checking is free. The first verified download every 30 days is free. After that €1.90 per invoice, or €9 a month for all of them.