E-invoicing in Slovakia: A Complete Guide for Businesses

What is Slovakia e-invoicing?

Slovakia introduced mandatory B2B e-invoicing from 1 January 2025 through its IS EFA (Informačný systém elektronickej fakturácie — Electronic Invoicing Information System), operated by the Finančná správa (Slovak Financial Administration). Slovakia is one of the first EU member states to implement a full B2B e-invoicing mandate via a Peppol-based platform rather than a proprietary clearance system.

The IS EFA mandate requires all Slovak VAT-registered entities — both suppliers and buyers — to issue and receive invoices through the Peppol network. Unlike Italy's SDI, invoices are not cleared by the government authority before delivery; instead, IS EFA acts as a monitoring and registration layer. Suppliers must be registered on the Slovak Peppol network and issue invoices in Peppol BIS Billing 3.0 format.

The mandate was introduced under amendment to the Slovak VAT Act (zákon o dani z pridanej hodnoty) and the associated decree specifying technical requirements for the IS EFA system.

The Peppol BIS Billing 3.0 format

Slovakia uses Peppol BIS Billing 3.0 as the mandatory format for IS EFA. Key technical characteristics:

• Standard: Peppol BIS Billing 3.0 (EN 16931 CIUS), delivered via IS EFA
• Syntax: UBL 2.1 (required for IS EFA)
• Participant identifier scheme: 9915 (Slovak VAT number) or Slovak IČO (company registration number) — the Finančná správa assigns Peppol IDs based on IČO
• VAT: standard 20%, reduced 10% (medicines, food staples, books)
• IS EFA routing: all invoices must pass through IS EFA's Peppol access point infrastructure; direct peer-to-peer Peppol delivery outside IS EFA does not satisfy the mandate
• Invoice registration: IS EFA assigns each invoice a unique registration number (evidenčné číslo) confirming it has been processed by the system

Who does it apply to?

The mandate covers all sectors and all company sizes. There is no phased rollout or revenue-based threshold — the January 2025 date applied universally to all Slovak VAT registrants.

Timeline / key dates

• 2019: B2G Peppol e-invoicing mandate for public procurement
• 2022–2023: IS EFA system developed and piloted by Finančná správa
• 2024: IS EFA voluntary phase; businesses encouraged to register and test
• 1 Jan 2025: Full B2B mandatory — IS EFA/Peppol required for all Slovak VAT entities

How Clearvo handles Slovakia e-invoicing

Clearvo is registered as a Peppol Access Point and supports routing through the Slovak IS EFA infrastructure. IS EFA requires invoices to pass through its designated Peppol gateway; Clearvo handles this routing transparently.

Key points:

• Slovak recipients are identified by IČO-based Peppol ID via the IS EFA participant registry
• Clearvo performs a live IS EFA participant lookup before sending to confirm registration status
• The IS EFA evidenčné číslo (registration number) is returned in the API response and stored per invoice
• Standard Peppol BIS Billing 3.0 validation applies; IS EFA adds additional Slovak-specific business rules which Clearvo validates before submission

What you send: standard invoice fields plus customer.peppolId (IS EFA-registered), supplierVatNumber (SK format), and buyerCountry: "SK".

What you get back: IS EFA registration number, Peppol delivery receipt, and the UBL 2.1 XML.

{
  "invoiceNumber": "INV-2025-00033",
  "issueDate": "2025-02-10",
  "dueDate": "2025-03-12",
  "currency": "EUR",
  "supplier": {
    "name": "Acme Software s.r.o.",
    "vatNumber": "SK2023456789",
    "ico": "50234567",
    "peppolId": "9915:2023456789",
    "address": {
      "street": "Obchodná 12",
      "city": "Bratislava",
      "postalCode": "811 06",
      "country": "SK"
    }
  },
  "customer": {
    "name": "Slovak Industries AS",
    "vatNumber": "SK2087654321",
    "ico": "40876543",
    "peppolId": "9915:2087654321",
    "address": {
      "street": "Hlavná 55",
      "city": "Košice",
      "postalCode": "040 01",
      "country": "SK"
    }
  },
  "lines": [
    {
      "description": "Software development services — February 2025",
      "quantity": 40,
      "unitPrice": 95.00,
      "taxRate": 20,
      "taxCategory": "S"
    }
  ],
  "paymentTerms": "30 days",
  "bankAccount": {
    "iban": "SK3112000000198742637541",
    "bic": "GIBASKBX"
  }
}

Getting started

IS EFA participant lookup, Slovak IČO-based Peppol ID setup, and IS EFA-specific business rules are documented at clearvo.io/docs. Clearvo supports the IS EFA test environment for pre-production invoice validation before going live on the Slovak network.

Related country guides

• Hungary — RTIR real-time reporting, B2B mandatory
• Austria — Peppol BIS 3.0, B2G mandatory
• Poland — KSeF clearance model, mandatory from February 2026