- E-invoices for Phase 1 (4 December 2021) are similar to current invoices, with minimum  additional fields:     a. For simplified tax invoices and their associated notes (usually issued for B2C transactions) a mandatory QR code.    b.For tax invoices and their associated notes (usually issued for B2B transactions), an optional QR code and mandatory VAT number of the buyer if the buyer is a registered VAT taxpayer. - There is no specific file format mandated for Phase 1, however, invoices must include the mandatory fields and must be issued from an electronic system meeting ZATCA’s requirements. In addition, electronic copies of all issued invoices must be stored by the taxpayer.​​