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DE-R-027:Invalid phone number format. The seller contact telephone number (BT-42) must contain at least 3 digits to be valid.

Invalid phone number format. The seller contact telephone number (BT-42) must contain at least 3 digits to be valid.

Why This Error Matters

Invoice will be rejected by German XRechnung validators. German e-invoicing has specific format requirements for payment details, contact information, and attachments.

Common Causes

  • Seller telephone number format invalid
  • BT-42 must contain at least 3 digits
  • cbc:Telephone too short or contains only text
  • Contact phone number not valid format
  • Telephone field contains non-numeric or too few characters

Frequently Asked Questions

Invalid phone number format. The seller contact telephone number (BT-42) must contain at least 3 digits to be valid.
Invalid phone number format. The seller contact telephone number (BT-42) must contain at least 3 digits to be valid. You can also use Invoice Navigator's automatic Fixer tool to correct this instantly.
DE-R-027 is a warning that may not always cause rejection, but it indicates a potential compliance issue that should be addressed.
Many instances of DE-R-027 can be automatically corrected using Invoice Navigator's Fixer tool. Upload your invoice and the tool will identify and fix common issues.

See Also

Last updated: 16 January 2026

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