How do I fix GR-R-006?

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.

Is GR-R-006 a critical error?

Yes, GR-R-006 is a critical error that will cause invoice rejection. It must be fixed before submission.

Can GR-R-006 be automatically fixed?

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.

errorGRCCIUS-GR (Greece)

`GR-R-006`:Greek Suppliers must provide the VAT number of the buyer, if the buyer is Greek

When both supplier and buyer are Greek, the buyer's VAT number must be provided. This is required for domestic Greek transactions.

Severity

Fatal

Rule set

CIUS-GR (Greece)

Country

GRC

Fix type

INPUT REQUIRED

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). It checks whether greek suppliers must provide the vat number of the buyer, if the buyer is greek.

When this rule fires, the invoice is non-compliant and will be rejected by Peppol access points and national validation services. The sending system receives a rejection response and the invoice does not reach the buyer.

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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. Invoices that trigger this rule are rejected at the access point and never reach the recipient. In Peppol networks, this means your sending system receives an MLR (Message Level Response) with a rejection status. The invoice must be corrected and re-sent, adding delay to your payment cycle.

Validator Behavior

·Causes invoice rejection
·Error returned: GR-R-006
·Specification: CIUS-GR (Greece)

Before / After

Failing XML

<Invoice>
  <!-- Issue: Greek Suppliers must provide the VAT number of the buyer, if -->
</Invoice>

Corrected XML

<Invoice>
  <!-- Issue resolved per CIUS-GR (Greece) -->
</Invoice>

Technical Reference

SpecCIUS-GR (Greece)

StrategyRequires user input: Greek buyer VAT number (EL + 9 digit TIN). User must provide buyer's registered Greek VAT.

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 →

Related Errors

GR-R-003

Greek invoice type code required

GR-R-009

Greek suppliers must use their correct TIN as the electronic address for...

GR-S-011

Greek suppliers must provide their Seller Tax Registration Number, prefixed...

Last updated: 27 February 2026

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The compliance engine auto-remediates this error with controlled safety policies and evidence pack generation.

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GR-R-006:Greek Suppliers must provide the VAT number of the buyer, if the buyer is Greek