San Marino extends HUB-SM clearance e-invoicing regime to domestic B2B transactions from 1 January 2027
This builds on the SdI system already used for trade with Italy
Update 10 September 2026: the proposed e-invoicing technical specification has been adopted for mandatory electronic invoicing for domestic transactions between resident economic operators from 1 January 2027.
Delegated Decree No. 133 of 4 September 2026 extends the country’s existing centralised clearance e-invoicing modelto domestic supplies of goods and services.
Rather than adopting a Peppol-style decentralised network, invoices will pass through HUB-SM, the government e-invoicing platform operated by the San Marino Tax Office.
From Italy e-invoicing to domestic clearance
San Marino electronic invoicing programme dates back to 2021, when legislation and technical rules were introduced for electronic invoices exchanged with Italian businesses.
A voluntary transition began on 1 October 2021, before electronic invoicing became mandatory for qualifying San Marino operators trading with Italy from 1 July 2022. HUB-SM was established as San Marino’s gateway to Italy’s Sistema di Interscambio, SdI, receiving and transmitting structured XML invoices between the two countries.
The 2027 reform effectively brings that infrastructure inside San Marino’s domestic economy.
The government had already identified domestic B2B e-invoicing as the next stage of the programme, citing the positive experience of the Italy regime and its potential to improve transaction traceability, tax controls and the future pre-population of tax declarations.
HUB-SM clearance model
Under the domestic regime, suppliers will transmit structured electronic invoices through HUB-SM.
The basic model is:
Supplier → HUB-SM → Customer
HUB-SM acts as the central tax authority platform for receiving and validating invoice data before it is passed to the recipient. San Marino’s existing infrastructure supports both direct Web Service connections and access through its TribWEB portal.
This places San Marino broadly in the Italy-style clearance / continuous transaction control model, rather than relying simply on periodic invoice reporting.
€100,000 small business exemption
Operators whose revenues did not exceed €100,000 in the previous calendar year may continue issuing paper invoices.
They may opt voluntarily for electronic invoicing. Once the election is made, however, electronic invoicing will continue to apply in subsequent years.
Two-month invoice deadline
San Marino’s regime differs from many newer CTC systems by allowing a relatively long invoicing window.
- Goods, invoices must be issued and transmitted within two months of delivery or shipment
- Services, the deadline is two months from completion of the service.
The same deadlines apply to businesses that remain eligible to issue paper invoices.
The result is an unusual combination of central tax authority clearance with comparatively relaxed invoice issuance deadlines.
Voluntary transition from October 2026
Businesses may start using domestic electronic invoicing voluntarily from 1 October 2026, providing a three-month transition before the mandate begins on 1 January 2027.
Failure to issue or transmit an invoice will attract an administrative penalty of €100.
However, penalties will only apply from 1 January 2028, effectively providing a full calendar year after mandatory implementation for businesses to stabilise their systems and processes.