GR-R-006: Greek Suppliers must provide the VAT number of the buyer…

StandardPeppol BIS Billing 3.0 country rules (NL, DE, IT, SE, DK, NO, GR, IS)CountryGreeceSeverityError: the invoice is rejectedSyntaxUBLApplies toOnly when the seller (or for some rules the buyer) is in the named country: the rule is triggered by the country code of the party. Dutch rules implement NLCIUS, German rules the XRechnung requirements inside Peppol.

Official rule text

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

Why this error occurs

This rule only applies when another field has a certain value (for example a payment means code or an invoice type). Your file triggers the condition but does not provide the data that then becomes mandatory, or provides data that is then forbidden.

How to fix it

Either change the triggering value so the condition no longer applies, or add/remove the dependent elements as the rule text describes. Check the condition in the XPath test above to see exactly which value triggers it.

What the validator checks

Checked element (context):

UBL

cac:AccountingCustomerParty[$isGreekSenderandReceiver]/cac:Party

Test (XPath):

count(cac:PartyTaxScheme[normalize-space(cac:TaxScheme/cbc:ID) = 'VAT']/cbc:CompanyID)=1 and
				                        substring(cac:PartyTaxScheme[normalize-space(cac:TaxScheme/cbc:ID) = 'VAT']/cbc:CompanyID,1,2) = 'EL' and
				                        u:TinVerification(substring(cac:PartyTaxScheme[normalize-space(cac:TaxScheme/cbc:ID) = 'VAT']/cbc:CompanyID,3))

Check your invoice

Drop your XML or PDF on the validator and every failed rule is linked to its page here. Free, no account, the file is not stored.

Check your invoice →

Same check via API:

curl -F file=@invoice.xml https://einvoicechecker.com/v1/validate

Related rules

GR-R-002 Greek Suppliers must provide their full name as they are registered in the Greek…
GR-R-003 For the Greek Suppliers, the VAT must start with 'EL' and must be a valid TIN number
GR-R-005 Greek Suppliers must provide the full name of the buyer
GR-R-009 Greek suppliers that send an invoice through the PEPPOL network must use a correct TIN…
GR-R-010 Greek Suppliers that send an invoice through the PEPPOL network to a greek buyer must…

Frequently asked questions

What does GR-R-006 mean?

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

Will my invoice be rejected because of GR-R-006?

Yes. GR-R-006 is flagged "fatal"; validators (KoSIT, Peppol access points, the German ZRE/OZG-RE portals, KSeF) reject the invoice until it is fixed.

Which formats does GR-R-006 apply to?

Only when the seller (or for some rules the buyer) is in the named country: the rule is triggered by the country code of the party. Dutch rules implement NLCIUS, German rules the XRechnung requirements inside Peppol. Syntax: UBL.

Source: Peppol BIS Billing 3.0.20 national rules (November 2025). Catalogue generated from the official rule sets on 2026-10-15.

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