San Marino Introduces Mandatory Domestic E-Invoicing

San Marino has enacted Delegated Decree No. 133, dated September 4, 2026, extending the country’s e-invoicing regime to domestic transactions between Sammarinese economic operators. The reform brings the country’s existing electronic invoicing infrastructure, first built for cross-border trade with Italy, into its domestic economy, with mandatory compliance beginning on January 1, 2027.

Scope of the Mandate

The obligation applies to domestic supplies of goods and services exchanged between Sammarinese economic operators, agricultural businesses, and public or private entities holding an economic operator code (codice operatore economico, or COE), a five-digit fiscal identifier already in use under the Italian cross-border regime. Both supplier and customer must be established or identified in San Marino and hold a COE, or be treated as equivalent, for the mandate to apply.

Operators whose revenue in the prior calendar year was below EUR 100,000 are outside the mandatory scope and may continue issuing paper invoices, though they may voluntarily opt into electronic invoicing. Once an operator crosses that threshold or opts in, e-invoicing becomes compulsory for every subsequent year.

The State, the Public Administration, and other public entities also fall within the scope, but only once the Congress of State adopts the separate implementing provisions envisaged in the decree for the public sector.

Implementation Timeline

• October 1–December 31, 2026: voluntary phase, allowing businesses to begin issuing domestic e-invoices ahead of the mandate.
• January 1, 2027: mandatory e-invoicing takes effect for Sammarinese economic operators that do not qualify for the EUR 100,000 revenue exemption; paper-invoice rules for exempt operators also become effective.
• January 1, 2028: administrative penalties of EUR 100 begin to apply for late or omitted transmission of e-invoices or variation notes, for failing to prepare, deliver, or send required paper invoices, and for non-compliance with the missing-invoice procedure.

Invoice Transmission and Deadlines

In-scope invoices must be prepared and transmitted electronically through Hub SM, the government platform already used for e-invoicing with Italy, to the Tax Office (Ufficio Tributario). Each transmitted file is assigned a unique HASH code. Operators can connect via a direct Web Service link or through the existing TribWEB portal.

• Goods: invoices must be issued and transmitted by the end of the second month following delivery.
• Services: the same two-month deadline runs from completion of the service or from receipt of an advance payment, whichever comes first.
• Continuous supplies exceeding one year with no interim payments: invoices must instead be transmitted by the end of the second month following the close of each calendar year, for as long as the supply continues.

Early transmission is permitted. Any e-invoice rejected by Hub SM is treated as though it were never issued, and once the Tax Office completes its checks, accepted invoices are made available electronically to the buyer or service recipient.

Paper Invoices, Credit Notes, and Missing Invoices

Operators that remain exempt and do not opt in must continue issuing paper invoices that include the same information required for e-invoices, within the same deadlines. These generally need not be sent to the Tax Office, except in the specific circumstances described below.

Credit notes and other variation notes must follow the format of the original invoice: electronically through Hub SM if the original was an e-invoice, or on paper if the original was a paper invoice.

Where a buyer or recipient has not received an expected invoice or variation note, it must wait two months beyond the applicable deadline before acting, then has a further 30 days to submit a document reproducing all the missing invoice’s details, either through Hub SM or, for parties not required to transmit e-invoices, directly on paper to the Tax Office.

Technical Rules, Archiving, and Retention

The Congress of States is expected to issue additional technical and procedural rules governing the preparation, transmission, and receipt of e-invoices, while archiving and preservation will be addressed under separate regulations. Hub SM will allow operators to consult and retrieve their e-invoices, though the Tax Office will not act as a third-party archiving provider. In the meantime, existing retention rules continue to apply and currently require invoices to be retained for 5 years from the end of the relevant tax period, or until any related tax assessment becomes final.

There’s more you should know about global e-invoicing changes – learn more about the new and upcoming regulations.