KOSIT Validator Error Codes: Complete Guide to XRechnung and ZUGFeRD Validation Errors [2025]

Are you getting validation errors when submitting your XRechnung or ZUGFeRD invoice? This comprehensive guide explains all KOSIT validator error codes, what they mean, and how to fix them instantly.

When your e-invoice fails KOSIT validation, finding clear explanations for cryptic error codes like BR-DE-15 or UBL-CR-646 can be frustrating. Whether you're encountering "Leitweg-ID fehlt" or "Pflichtfeld fehlt" errors, this guide provides immediate solutions for every KOSIT validator error message.

What is the KOSIT Validator and Why Do E-Invoices Fail Validation?

The KOSIT (Koordinierungsstelle für IT-Standards) validator is Germany's official tool for validating electronic invoices in XRechnung and ZUGFeRD formats. With mandatory B2B e-invoicing starting in 2025, understanding these validation errors is crucial for successful invoice submission to German government portals and business partners.

The validator checks your invoice against:

• 21 German-specific business rules (BR-DE codes)
• European EN16931 standard requirements
• XML schema compliance (UBL or CII)
• PDF/A-3 standards (for ZUGFeRD only)

Most Common KOSIT Validator Error Codes and How to Fix Them

BR-DE-15: Leitweg-ID Missing or Invalid ("Leitweg-ID fehlt")

Error Message: "Das Element 'Buyer reference' (BT-10) muss übermittelt werden"

What it means: Your invoice is missing the Leitweg-ID, a mandatory routing identifier for German public sector invoices.

How to fix it:

1. Obtain the correct Leitweg-ID from your customer (format: XX-XXXXXX-XX-XXXXX)
2. Add it to the BuyerReference (BT-10) field
3. Ensure it doesn't exceed 40 characters
4. Include hyphens in the exact positions specified

BR-DE-21: Invalid XRechnung Specification Identifier

Error Message: "Specification identifier MUST have the value 'urn:cen.eu:en16931:2017#compliant#urn:xrechnung:3.0'"

What it means: Your invoice incorrectly identifies its format version, often mixing ZUGFeRD and XRechnung specifications.

How to fix it:

• For XRechnung 3.0: Use exactly urn:cen.eu:en16931:2017#compliant#urn:xrechnung:3.0
• For XRechnung 2.3: Use urn:cen.eu:en16931:2017#compliant#urn:xrechnung:2.3
• Don't mix ZUGFeRD profile identifiers with XRechnung

BR-DE-5, BR-DE-6, BR-DE-7: Missing Seller Contact Information ("Pflichtfeld fehlt")

BR-DE-5: "Seller city MUST be provided"

BR-DE-6: "Seller post code MUST be provided"

BR-DE-7: "Seller contact telephone number MUST be provided"

What it means: German regulations require complete seller contact details, unlike some EU countries.

How to fix it:

• BR-DE-5: Add seller's city name
• BR-DE-6: Include complete postal code
• BR-DE-7: Provide a valid phone number (with country code)

UBL-CR-646: SubInvoiceLine Not Allowed

Error Message: "A UBL invoice should not include the SubInvoiceLine"

What it means: Your invoice contains sub-invoice line elements that aren't permitted in XRechnung UBL format.

How to fix it:

1. Remove all SubInvoiceLine elements from your XML
2. Flatten hierarchical line items into simple invoice lines
3. Check your ERP export settings to disable sub-line generation

PEPPOL-EN16931-R008: Empty Elements Detected

Error Message: "Document MUST not contain empty elements"

What it means: Your XML contains tags with no content, which XRechnung 3.0 strictly prohibits.

How to fix it:

• Remove all empty XML tags (e.g., <Description></Description>)
• Ensure optional fields are completely omitted if not used
• Validate that your XML generator doesn't create placeholder tags

XRechnung Version-Specific Validation Errors

XRechnung 3.0 New Mandatory Fields (Since February 2024)

BT-34 & BT-49: Electronic Address Required

"Seller electronic address MUST be provided"

"Buyer electronic address MUST be provided"

What it means: XRechnung 3.0 made electronic addresses mandatory for both parties.

How to fix it:

• Add seller's email in BT-34 field
• Include buyer's email in BT-49 field
• Use format: EM:email@domain.com for email addresses

BR-CO-10 & BR-S-08: VAT Calculation Errors

Error Message: "VAT amount = taxable amount × (rate / 100)"

What it means: Your VAT calculations don't match the required precision (2 decimal places).

How to fix it:

1. Recalculate: VAT = Taxable Amount × (VAT Rate / 100)
2. Round to exactly 2 decimal places
3. Ensure sum of line-level VAT equals invoice-level VAT

ZUGFeRD Validation Errors and PDF/A Compliance

PDF/A-3 Compliance Failures ("PDF/A nicht konform")

Common ZUGFeRD-specific errors:

• ISO 19005-3:2012 Violations:
• • "XMP Metadata invalid value"
• • "Embedded file not found"
• • "PDF/A identification missing"

How to fix PDF/A errors:

1. Ensure PDF is saved as PDF/A-3
2. Embed XML as factur-x.xml (for ZUGFeRD 2.x)
3. Include proper XMP metadata describing the embedded invoice

ZUGFeRD Profile Mismatches ("Profil nicht unterstützt")

Error Message: "ZUGFeRD profile not supported for this validation"

Available profiles and when to use them:

• MINIMUM: Basic invoice data only
• BASIC: Standard business invoices
• EN 16931: European standard compliance
• XRECHNUNG: German public sector (use XRechnung format instead)
• EXTENDED: Additional custom fields

How to Validate Your E-Invoice Before Submission

Step-by-Step Validation Process

1. Choose the correct format:
   • XRechnung for German public sector
   • ZUGFeRD for B2B with PDF requirement
2. Select the right version:
   • XRechnung 3.0 (current)
   • ZUGFeRD 2.3 (latest)
3. Pre-validate mandatory fields:
   • Leitweg-ID (BR-DE-15)
   • Seller contact details (BR-DE-5, 6, 7)
   • Tax registration (BR-DE-16)
   • Electronic addresses (BT-34, BT-49)
4. Use Invoice-Converter.com's free validator:
   • Upload your XML or PDF file
   • Get instant error explanations in plain language
   • Download corrected invoice

Quick validation tip: Use our PDF to XRechnung converter to automatically generate compliant invoices, or try our universal converter for all formats.

Common Search Queries Answered

"Was bedeutet Fehler BR-DE-1?"

BR-DE-1 requires payment information when payment terms are provided. Include IBAN/BIC or payment method details.

"Wie validiere ich eine XRechnung?"

Use Invoice-Converter.com's free XRechnung validator or the official KOSIT validator tool. Upload your XML file and review the validation report.

"E-Rechnung wird abgelehnt - was tun?"

Check the validation report for specific error codes, fix mandatory field errors first (BR-DE codes), then address calculation and format issues.

"XRechnung Pflichtfelder Liste"

Mandatory fields include: Invoice number, issue date, seller details, buyer details, Leitweg-ID (public sector), tax information, line items, and totals.

Quick Error Code Reference Table

Industry-Specific Validation Challenges

Automotive Sector

Differential Taxation

Special VAT rules for used parts require specific tax category codes. Use "AE" (reverse charge) or "E" (exempt) with proper justification text.

Healthcare

Medical Device Identification

UDI (Unique Device Identification) must follow specific formatting in item descriptions.

Construction

Reverse Charge Procedures

Bauleistungen (construction services) require special tax category "AE" with reference "Reverse charge".

Get Instant Validation with Invoice-Converter.com

Stop struggling with cryptic error messages. Invoice-Converter.com provides:

• Instant error translation - German and English explanations
• One-click fixes - Automatic correction of common errors
• Format conversion - Convert between XRechnung and ZUGFeRD
• Version migration - Update invoices to current standards
• Free validation - No registration required

Validate Your E-Invoice Now →

Stay Updated with E-Invoice Validation Changes

E-invoicing regulations and validation rules change regularly. Subscribe to Invoice-Converter.com's newsletter for:

• New error code explanations
• Version update notifications
• Industry-specific validation guides
• B2B e-invoicing mandate updates

Last updated: September 2025 | Version: XRechnung 3.0, ZUGFeRD 2.3

Keywords: KOSIT validator, XRechnung validation errors, ZUGFeRD errors, E-Rechnung validieren, BR-DE-15, Leitweg-ID fehlt, Pflichtfeld fehlt, XRechnung 3.0 errors, e-invoice validation, KOSIT error codes, XRechnung fehler, ZUGFeRD validation, German e-invoicing