E-invoicing in Slovenia: the 2028 e-SLOG mandate
Slovenia is making business-to-business e-invoicing mandatory from 1 January 2028. Under the ZIERDED law, adopted by the National Assembly on 23 October 2025, all entities in the Slovenian Business Register must exchange invoices electronically in the national e-SLOG format (or an EN 16931-compliant equivalent). Paper invoices remain allowed only towards consumers and foreign parties.
When is e-invoicing mandatory in Slovenia?
Business-to-business e-invoicing becomes mandatory in Slovenia on 1 January 2028. This date comes from the ZIERDED law, adopted by the National Assembly on 23 October 2025. Note that the correct date is 2028, not 2027 as some earlier drafts suggested.
Who must comply with the Slovenian mandate?
All entities registered in the Slovenian Business Register must issue and receive e-invoices for B2B transactions from 1 January 2028. Paper invoicing remains permitted only for business-to-consumer transactions and towards foreign parties who are not covered by the mandate.
What format is a Slovenian e-invoice?
The Slovenian standard is e-SLOG, a national XML format that maps to the European standard EN 16931. EN 16931-compliant formats, including invoices exchanged over Peppol, are also valid. Our validator supports e-SLOG 2.0 directly, so you can check a Slovenian invoice against its rules.
How are e-invoices exchanged in Slovenia?
Slovenia allows several exchange routes: certified e-route providers, direct exchange between trading partners, and the Peppol network. The tax administration also offers a free application (miniBlagajna) for the smallest issuers, so even businesses without dedicated invoicing software can comply.
Why was my e-SLOG invoice rejected?
Common causes are missing mandatory fields required by the e-SLOG rules: no document number, no issue date, no currency code, no invoice lines, or a missing seller VAT identifier. Each of these maps to a specific e-SLOG rule you can look up and fix before resending.
e-SLOG rules invoices commonly fail
These are the core e-SLOG 2.0 checks — each links to its explanation and fix: SI-ESLOG-R001 (document number), SI-ESLOG-R002 (issue date), SI-ESLOG-R003 (currency), SI-ESLOG-R004 (at least one line), SI-ESLOG-R005 (seller VAT identifier). See the e-SLOG 2.0 format page or validate an invoice free.
Official sources
- ZIERDED — PISRS (official register of Slovenian legislation)
- FURS — Financna uprava Republike Slovenije
Related: EU mandate timeline · e-SLOG 2.0 · free validator.