Slovenia — e-SLOG + UJP: universal B2G since 2015

Slovenia is one of the European pioneers of mandatory B2G: since 1 January 2015, every invoice to public administrations must transit through UJP (Uprava Republike Slovenije za javna plačila) in the national e-SLOG XML 2.0 format. A universal B2B obligation is announced for 2026 as part of the ViDA transposition, with an EN 16931-aligned e-SLOG profile.

Regulatory timeline

• 2003 — Initial GZS work. The Slovenian Chamber of Commerce (Gospodarska zbornica Slovenije, GZS) initiates the national e-SLOG standard for B2B electronic invoicing, inspired by EDIFACT and early UBL drafts.
• 2010 — e-SLOG 1.5 published: first industrial version adopted by major sectors (energy, retail).
• 14 November 2014 — ZOPSPU-1. Zakon o opravljanju plačilnih storitev za proračunske uporabnike Act making e-invoicing mandatory to state budget users via UJP.
• 1 January 2015 — Universal mandatory B2G. All invoices to Slovenian public administrations transit through UJP. Slovenia becomes the first EU country to impose universal mandatory B2G e-invoicing.
• 2018 — e-SLOG 2.0 published, aligned with EN 16931 and compatible with PEPPOL BIS Billing 3.0.
• 2024-2025 — B2B consultation. The Ministrstvo za finance opens consultation on mandatory B2B generalisation from 2026, consistent with the ViDA proposal.
• 2026 — Target B2B obligation. Schedule being finalised in Q4 2025.

Deep dives — 10 dedicated pages

Ten dedicated pages drill into every dimension of the Slovenian e-invoicing and EDI ecosystem — the pioneering reforms (B2G eRačun 2015, UJP unified payment + e-invoice hub, real-time POS certification 2016, ViDA 2028 roadmap), the technical specifications (e-SLOG XML, AJPES corporate registry, eDavki tax portal, DDV VAT regimes), and the real-world B2B usage that long pre-dates and coexists with EU regulation (retail EDIFACT, industrial OFTP2 automotive + pharma + white goods).

Pioneering reforms

• eRačun — B2G mandatory since 1 January 2015 · Universal B2G mandate among the oldest in the EU (on par with Denmark). ZOPSPU-1 framework (Uradni list RS 77/2016), UJP hub, ~3,500 public entities. Format e-SLOG 2.0 + PEPPOL BIS 3.0.
• UJP — public payments administration + e-invoice hub · A Ministry of Finance service fusing B2G e-invoice intake + budget payment execution. Unique in the EU. ~6M e-invoices/year + ~15M payments/year. PEPPOL Authority since 2018.
• Davčno potrjevanje — real-time POS fiscal certification since 2016 · ZDavPR (Uradni list RS 57/2015) effective 2 January 2016: every B2C receipt sent real time to FURS via REK web service, ZOI + EOR + QR printed. +€80-100M VAT revenue from year one.
• ViDA — Slovenia roadmap 2028 · No B2B mandate in force. FURS 2024-2025 consultation, 2026-2027 legislative project, large-company go-live 1 Jan 2028. 5-corners model UJP + certified operators. Strong position thanks to 2015 B2G eRačun + 2016 REK POS.

Technical specs

• e-SLOG 2.0 — national XML format since 2003 · Hybrid XML schema wrapping UN/EDIFACT INVOIC D.01B, published 2003 by GZS + ZZI. Version 2.0 EN 16931-aligned (2018). ~85% of B2G + ~70% of large-account B2B. Namespace urn:eslog:2.00.
• AJPES — national registry and matična številka · Ministry of Justice agency running PRS (Poslovni register Slovenije). 7-digit immutable matična številka = PEPPOL ICD 0177. ~190,000 companies + ~3,500 public entities. REST OAuth2 APIs + EU BRIS.
• eDavki — FURS tax portal and voluntary SAF-T · Single window for 100% of Slovenian tax filings (DDV-O, DOHOD, DOPL, RP-O). SIGEN-CA eIDAS authentication. Voluntary OECD SAF-T since 2015. REST OAuth2 APIs since 2024 on apis.fu.gov.si. 99.8% dematerialised.
• VAT (DDV) — 22 / 9.5 / 5% regimes and ZDDV-1 · Slovenian VAT: 22% standard, 9.5% reduced, 5% super-reduced (books). ZDDV-1 framework (Uradni list RS 117/2006). SI prefix + 8 digits. ~140,000 taxable persons, ~€4.2B revenue/year. €50K threshold since 2022.

Real-world B2B usage

• Retail EDIFACT — Mercator, Spar, Hofer, Lidl, Tuš, Eurospin · Retail fabric shaped by Mercator (Fortenova HR since 2019), Spar Slovenija (AT), Hofer (Aldi), Lidl (DE), Tuš, Eurospin (IT). EANCOM 2002 S4 GS1 Slovenia prefix 595. ~250M EDIFACT messages/year, ~6,500 suppliers.
• Industrial EDI — Krka, Gorenje, Revoz, Talum, Acroni · Five verticals: pharma (Krka Novo mesto), white goods (Gorenje/Hisense Velenje), automotive (Revoz/Renault Novo mesto Twingo/Clio/Captur), aluminium (Talum), steel (Acroni/SSAB). OFTP2 ENX + EANCOM 2002 S4. ~80 OFTP2 endpoints, ~340 EDIFACT industrials.

Technical schema

Two formats coexist in Slovenia:

• e-SLOG XML 2.0 — national format managed by GZS, XML structure aligned with EN 16931 but with its own tags and business rules (SI-specific Sklic — payment reference fields).
• PEPPOL BIS Billing 3.0 (UBL 2.1) — accepted by UJP since 2019; recommended for cross-border flows.

National identifiers:

• Davčna številka — 8 digits (SI tax number).
• Matična številka — 7 + 3 digits (company number).
• PEPPOL schemeID: 9908 for SI:VAT (SI + 8 digits).
• Sklic: structured payment reference (00, 11, 12, 18, 19, 21, 99) mandatory for SI bank reconciliation.

<?xml version="1.0" encoding="UTF-8"?>
<Invoice xmlns="urn:eslog:2.00"
         xmlns:cbc="urn:un:unece:uncefact:documentation:2"
         xmlns:cac="urn:un:unece:uncefact:codelist:standard">
  <cbc:CustomizationID>urn:cen.eu:en16931:2017</cbc:CustomizationID>
  <cbc:ID>SI-2026-0142</cbc:ID>
  <cbc:IssueDate>2026-05-19</cbc:IssueDate>
  <cbc:DocumentCurrencyCode>EUR</cbc:DocumentCurrencyCode>
  <cac:AccountingSupplierParty>
    <cac:Party>
      <cac:PartyIdentification>
        <cbc:ID schemeID="9908">SI12345678</cbc:ID>
      </cac:PartyIdentification>
      <cac:PartyLegalEntity>
        <cbc:RegistrationName>Ediverse Demo Slovenija d.o.o.</cbc:RegistrationName>
      </cac:PartyLegalEntity>
    </cac:Party>
  </cac:AccountingSupplierParty>
  <cac:PaymentMeans>
    <cbc:PaymentMeansCode>30</cbc:PaymentMeansCode>
    <cbc:PaymentID>SI00 2026-0142</cbc:PaymentID>
  </cac:PaymentMeans>
</Invoice>

Submission flow

The Slovenian B2G model is centralised around UJP: the seller submits via its software vendor or via the bizBox platform (major SI integrator), UJP validates and archives, then forwards to the destination public body for payment.

┌──────────────┐    ┌────────────┐    ┌──────────────┐    ┌─────────────────┐
│ Seller SI    │───>│ bizBox /   │───>│ UJP          │───>│ SI public body  │
│ (ERP e-SLOG) │    │ PEPPOL AP  │    │ ujp.gov.si   │    │ (payment)       │
└──────────────┘    └────────────┘    └──────────────┘    └─────────────────┘

For B2B (voluntary in 2025, mandatory 2026), the bizBox network and the Slovenian PEPPOL access points (Bisnode, Pošta Slovenije, etc.) provide transport. No mandatory central B2B hub as of writing.

Validation

• UJP portal: gov.si/.../public-payments-administration/.
• e-SLOG 2.0 standard: XSD, code lists and examples published on gzs.si (Gospodarska zbornica Slovenije).
• PEPPOL validator: peppol.helger.com for UBL flows.
• FURS (Financial Administration): fu.gov.si — tax administration, runs SI SAF-T and the related filing obligations.

Common pitfalls

1. Malformed Sklic. The Slovenian payment reference (Sklic) follows a strict format SI<model> <reference> with a MOD 11 check digit. An invalid Sklic blocks bank reconciliation and triggers a correction request from the public debtor.
2. e-SLOG vs PEPPOL UBL confusion. Both formats are accepted but structurally different: do not use an e-SLOG template just swapping in UBL namespaces. Vendors that do produce XML that is valid but semantically empty.
3. UJP mandatory metadata. Beyond EN 16931 fields, UJP requires the Številka naročilnice (public order number) and the SAP številka (recipient internal reference). Absence = UJP rejection with code UJP-MD-01.
4. 22% VAT rate. The Slovenian standard rate is 22% (not 23 as in SK or 21 as in NL). Frequent mistake when reusing pan-European rate tables.
5. UTF-8 without BOM. UJP rejects XML files with a UTF-8 BOM (leading EF BB BF bytes). Windows tools that prepend the BOM by default (Notepad, some Excel exports) trigger immediate rejection.

Cross-links

• Croatia — Balkan neighbour, Fiscalizacija 2.0.
• Austria — Alpine neighbour, ebInterface, comparison of B2G pioneers.
• Hungary — V4-adjacent neighbour, NAV Online Számla.
• PEPPOL — network supported by UJP.
• Official sources: gov.si — elektronsko poslovanje, gzs.si — e-SLOG 2.0, Uradni list — ZOPSPU-1.