San Marino Introduces Mandatory Domestic B2B E-Invoicing from January 2027

• San Marino’s Delegated Decree No. 133 of 4 September 2026 introduces electronic invoicing for domestic sales of goods and services between qualifying economic operators. [kpmg.com], [vatcalc.com]
• The system is available voluntarily from 1 October to 31 December 2026 and becomes mandatory for in-scope domestic transactions from 1 January 2027. [kpmg.com], [e-invoice.app], [vatfaqs.com]
• Operators with prior-year revenue below EUR 100,000 are exempt but may opt into the electronic-invoicing system. Invoices are transmitted through San Marino’s HUB-SM platform. [kpmg.com], [e-invoice.app], [vatcalc.com]

Source 

• The technical specifications: Regulation No. 28/2026
• Dedicated section on the website of the State Secretariat for Finance and Budget.

Extended article

San Marino has adopted a domestic electronic-invoicing mandate through Delegated Decree No. 133 of 4 September 2026.

The new framework extends electronic invoicing to domestic supplies between Sammarinese economic operators. This builds on the electronic-invoicing infrastructure already used for qualifying transactions between San Marino and Italy. [kpmg.com], [e-invoice.app], [vatcalc.com]

The implementation follows a phased timetable:

• 1 October to 31 December 2026: voluntary use of electronic invoicing for domestic transactions;
• 1 January 2027: mandatory electronic invoicing for in-scope domestic transactions; and
• 1 January 2028: application of the reported administrative penalties for late or omitted transmission. [kpmg.com], [vatfaqs.com]

The mandate covers domestic sales of goods and services between economic operators. The reported scope includes businesses, agricultural enterprises and public or private entities holding an economic-operator code, although application to the State and public bodies depends on the adoption of implementing regulations. [kpmg.com], [e-invoice.app]

Operators whose revenue did not exceed EUR 100,000 in the preceding calendar year are exempt and may continue issuing paper invoices. They may nevertheless opt into electronic invoicing. Public descriptions of the regime state that an operator that opts in or exceeds the threshold becomes subject to electronic invoicing in subsequent years. [kpmg.com], [e-invoice.app]

Domestic e-invoices must be prepared and transmitted through HUB-SM to San Marino’s Tax Office. The available reports describe HUB-SM as the central platform receiving the structured invoice before it is made available to the recipient. [kpmg.com], [vatcalc.com]

Correcting documents must follow the same format as the invoice to which they relate. The reported transmission deadline is the second month following delivery for goods or completion for services. Separate timing applies to qualifying continuous supplies. [kpmg.com], [vatfaqs.com]

The regime should not be confused with the earlier San Marino–Italy e-invoicing framework. The earlier framework concerns cross-border transactions with Italy, while Decree No. 133 extends structured invoicing to domestic transactions within San Marino. [kpmg.com], [e-invoice.app], [vatcalc.com]

External links

• Read the KPMG analysis of San Marino’s domestic e-invoicing mandate [kpmg.com]
• Review the detailed San Marino e-invoicing timeline and scope [e-invoice.app]
• Read the overview of San Marino’s HUB-SM domestic mandate [vatcalc.com]
• Review the domestic B2B mandate, exemption and penalty dates [vatfaqs.com]