San Marino has published Regulation No. 14 of 8 September 2021, which establishes the technical and procedural rules for the formation, issuance, transmission, and receipt by San Marino economic operators of electronic invoices in the exchange of goods and services with Italy. The rules concern the cross-border system announced in June 2021 that allows for the issuance of electronic invoices for transactions between Italy and San Marino, the Sistema di Interscambio (SdI). The system will be operational and available for use on a voluntary basis from 1 October 2021 and will become mandatory from 1 July 2022.