Element

Use the CompanyID element of the AccountingCustomerParty element:

Name (Technical Name)	Cardinality	Description
Buyer Tax Identification Number (`Invoice/AccountingCustomerParty/Party/PartyTaxScheme/CompanyID`)	0..1	Used to provide the tax identification number of the customer.
Buyer Tax Scheme ID (`Invoice/AccountingCustomerParty/Party/PartyTaxScheme/TaxScheme/ID`)	0..1	The scheme to which the Buyer's tax ID belongs.

Restrictions

For EU-based Buyers outside of Poland, you must specify the European VAT ID in the Buyer Tax Identification Number element.
For Polish Buyers, you can use either the European VAT ID or the NIP.
For all other countries, you must specify the corresponding tax identifier ID.
If no tax identification number is available, you can omit the Buyer Tax Identification Number element.

Example

The following example uses a European VAT ID:

<ubl:Invoice>
    <!-- Code omitted for clarity --> 
    <cac:AccountingCustomerParty>
        <!-- Code omitted for clarity -->
        <cac:Party>
            <!-- Code omitted for clarity -->
            <cac:PartyTaxScheme>
                <cbc:CompanyID>DE123456789</cbc:CompanyID>
                <cac:TaxScheme>
                    <cbc:ID>VAT</cbc:ID>
                </cac:TaxScheme>
            </cac:PartyTaxScheme>
            <!-- Code omitted for clarity -->
        </cac:Party>
        <!-- Code omitted for clarity -->
    </cac:AccountingCustomerParty>
</ubl:Invoice>