1. The business partner must be entered in the address book, with their VAT number filled in and the "VAT payer" checkbox selected.
2. In the invoice, we select the posting rule that will carry the VAT fulfillment code: supply of goods or services.
If both of these conditions are met, Flexi will automatically set VAT lines 20 or 21, and the invoice will be reflected in the recapitulative statement.