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How does the Customer VAT Number field work in AvaTax?


I am working with customers in the European Union (EU), and I would like to know what impact the Customer VAT Number field has on transactions.




The Customer VAT Number field contains the buyer's VAT registration ID for VAT calculations. The AvaTax calculation engine uses this field to determine whether or not VAT should be applied to an international sale. Note: AvaTax does not validate VAT registration IDs during calculation.

Following the EU's new July 2021 VAT ecommerce reforms, Avalara enhanced VAT calculations to handle more complex scenarios. For more information about how VAT numbers may be used in the businessIdentificationNo field of the AvaTax API, see CreateTransaction Document level fields on the Avalara Developer website.

Middleman and Merchant VAT registration IDs can be specified at the line level as a transaction parameter. For more information, see CreateTransaction line level fields on the Avalara Developer website.

VAT Transaction Examples

The VAT Transaction Examples list on the Avalara Developer website contains example transactions for domestic reverse charges, B2C sales invoices, triangulation purchases, and more.

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