GR-R-006:Greek Suppliers must provide the VAT number of the buyer, if the buyer is Greek
Fix: This requires user input to resolve. Review the relevant cbc: and cac: elements in your Invoice XML and provide the correct value. (GR-R-006). Provide the required value in the free validator.
When both supplier and buyer are Greek, the buyer's VAT number must be provided. This is required for domestic Greek transactions.
Engine Classification
Business data required · Explicit input workflow · No assumptions made
Required input: Buyer VAT Number (AFM)
What is GR-R-006?
GR-R-006 is a fatal validation rule defined in the CIUS-GR (Greece) specification (GRC national rules).
When this rule fires, the invoice is rejected by Peppol access points and never reaches the buyer.
Why This Error Matters
Invoice will be rejected by Greek validation. Greek domestic transactions require buyer VAT for tax reporting.
GR-R-006 is a hard failure — the invoice must be corrected and re-sent before it can reach the recipient.
Validator Behavior
- ·Causes invoice rejection
- ·Error returned: GR-R-006
- ·Specification: CIUS-GR (Greece)
How to Fix It
Identify the missing data
When both supplier and buyer are Greek, the buyer's VAT number must be provided. This is required for domestic Greek transactions.
Provide the required value
This requires user input to resolve. Review the relevant cbc: and cac: elements in your Invoice XML and provide the correct value. (GR-R-006).
Re-validate your invoice
Upload the corrected invoice to confirm GR-R-006 is resolved.
Before / After
<Invoice> <!-- Issue: Greek Suppliers must provide the VAT number of the buyer, if --> </Invoice>
<Invoice> <!-- Issue resolved per CIUS-GR (Greece) --> </Invoice>
Technical Reference
Common Causes
- ·Buyer VAT number missing on Greek-to-Greek invoice
- ·Customer master data incomplete
- ·Private consumer sale missing buyer ID
- ·ERP does not enforce buyer VAT for domestic
- ·Buyer VAT stored but not exported
Seeing this in production? The API handles GR-R-006 automatically. See the fix response →
Frequently Asked Questions
When both supplier and buyer are Greek, the buyer's VAT number must be provided. This is required for domestic Greek transactions.
This requires user input to resolve. Review the relevant cbc: and cac: elements in your Invoice XML and provide the correct value. (GR-R-006). You can also use Invoice Navigator's compliance engine to correct this automatically in your pipeline.
Yes, GR-R-006 is a critical error that will cause invoice rejection. It must be fixed before submission.
Many instances of GR-R-006 can be automatically corrected using Invoice Navigator's compliance engine. The fix is applied in your pipeline with full audit evidence.
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Last updated: 14 April 2026
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