E-invoicing in Slovakia: mandate, timeline and compliance guide

Slovakia is moving to a mandatory, structured e-invoicing model for domestic B2B and B2G transactions from 1 January 2027. Built on the Peppol network and enforced by Law No. 385/2025 Z.z., the new regime replaces the current IS EFA portal with a decentralised 5-corner architecture and introduces near real-time tax reporting via the Slovak tax data document (SK TDD). This article explains the rules, the deadlines and what your business needs to do to stay compliant.

TL:DR Summary

• From 1 January 2027, all VAT-registered businesses established in Slovakia must issue and receive structured e-invoices for domestic B2B and B2G transactions
• Invoices must follow the Peppol BIS Billing 3.0 profile (UBL 2.1) with the Slovak CIUS, and be routed through an accredited Peppol Service Provider, known locally as a “digital postman”
• Each invoice must be accompanied by a Slovak tax data document (SK TDD) sent to the financial administration within 15 minutes of transmission
• Non-compliance can trigger fines of 10,000 EUR to 100,000 EUR per violation, plus loss of VAT deduction rights for the buyer
• Cross-border transactions come into scope on 1 July 2030, aligning with the EU’s VAT in the Digital Age (ViDA) framework

What is e-invoicing in Slovakia?

E-invoicing is the exchange of invoices in a structured, machine-readable format that can be issued, transmitted and received electronically without manual intervention. In Slovakia, structured e-invoicing is being turned from an optional practice into a mandatory framework covering both business-to-government (B2G) and business-to-business (B2B) transactions.

The reform is enacted through Law No. 385/2025 Z.z., which amends the Slovak VAT Act. It is aligned with the wider EU push for VAT in the Digital Age (ViDA) and builds on the European standard EN 16931.

At a high level, the new regime aims to:

• Modernise Slovakia’s VAT infrastructure
• Reduce VAT fraud through near real-time transaction visibility
• Standardise invoice content and delivery via Peppol
• Replace fragmented reporting obligations with a single, structured data flow

Understanding the Slovakia e-invoicing mandate

The Slovakia e-invoicing mandate introduces two hard deadlines that in-scope businesses need to prepare for.

Key deadlines

Who is in scope?

The obligation to **issue** e-invoices applies to domestic taxable persons registered for VAT under sections 4, 4b or 4c of the Slovak VAT Act. This includes:

• Standard domestic VAT payers with a fixed establishment in Slovakia
• Members of VAT groups
• Ex officio registered VAT groups

The obligation to receive e-invoices is broader: any domestic taxable person, including non-VAT payers such as certain landlords, must be able to receive structured Peppol invoices. This is because domestic VAT payers are legally required to issue e-invoices for all supplies to other taxable persons.

Explicitly out of scope in the first phase:

• Foreign entities registered for VAT under section 5 with no fixed establishment in Slovakia
• Business-to-consumer (B2C) invoicing
• Certain classified or security-sensitive supplies

From 1 July 2030, cross-border transactions with EU counterparties will also fall in scope. In parallel, the VAT control statement (kontrolný výkaz) and recapitulative statement (súhrnný výkaz) will be abolished, because invoice-level reporting via the SK TDD replaces them.

Penalties for non-compliance

The Slovak Financial Administration will enforce the mandate with strong financial penalties:

• Fines from 10,000 EUR to 100,000 EUR per violation
• Loss of the buyer’s right to deduct input VAT on non-compliant invoices
• Potential repeat sanctions for continued non-compliance

The new five corner Peppol model

Under the mandate, Slovakia adopts a decentralised five corner Peppol model. This replaces the centralised IS EFA portal with peer-to-peer routing via certified service providers, plus a dedicated corner for the tax authority.

The corners are:

• Corner 1 (C1): the seller’s ERP system, which generates the invoice data
• Corner 2 (C2): the seller’s accredited Digital Postman that validates and transmits the invoice
• Corner 3 (C3): the buyer’s accredited Digital Postman that receives the invoice and delivers it to the buyer
• Corner 4 (C4): the buyer’s ERP system, which posts the invoice
• Corner 5 (C5): the Financial Administration’s access point, which receives the SK tax data document

For every in-scope transaction, two documents flow in parallel:

• The commercial invoice (Peppol BIS Billing 3.0 in UBL 2.1) is routed C2 to C3 for delivery to the buyer
• The SK TDD, a companion XML file with extracted tax metadata, is routed to C5 for near real-time reporting

Both the seller’s and the buyer’s Access Point are required to submit their own TDD to the Financial Administration within 15 minutes of the underlying invoice event, so the tax authority sees the same transaction from both sides.

The Digital Postman requirement

Businesses cannot connect directly to the Slovak tax authority or exchange invoices peer-to-peer without an intermediary. Every in-scope company must route all invoices through an accredited Digital Postman, a certified Peppol Service Provider. Accreditation is granted by the Peppol Authority SK, which sits within the Financial Directorate of the Slovak Republic.

To become an accredited Digital Postman, providers must:

• Be legally established in the EU
• Demonstrate a clean criminal record for statutory representatives
• Pass technical conformance testing on the OpenPeppol Testbed for the Slovak CIUS
• Commit to log retention and information security obligations under section 76a of the VAT Act

Formats and identifiers

The technical requirements businesses need to comply with include:

• Invoice format: Peppol BIS Billing 3.0, based on UBL 2.1, using the Slovak CIUS v1.8
• Report format: SK tax data document (TDD) XML, based on the Peppol Slovakia TDD specification
• Participant identifier: Peppol scheme 0245 followed by the 10-digit Slovak tax identification number (DIČ), for example 0245:1234567890
• Transport: Peppol AS4
• Acknowledgements: Message level status (MLS) receipts must be produced within 10 minutes of receiving and validating a document

For archiving, both invoices and the associated SK TDD and MLS receipts must be kept in their original XML form for at least 10 years. The retention period is extended to 20 years for transactions involving immovable property.

How to achieve e-invoicing compliance in Slovakia

Reaching compliance with the Slovakia e-invoicing regime is more than just enabling a new file format. It typically involves several coordinated steps across finance, ERP and IT teams for a smooth sailing when in production.

1. Confirm your scope

Start by identifying whether your Slovak entity is a domestic VAT-registered taxable person with a fixed establishment. If so, you’re in scope for issuing e-invoices from 1 January 2027. Non-established entities registered for VAT under section 5 are exempt from issuing domestic e-invoices but will be affected by the cross-border phase in 2030.

In any case, don’t forget the receiver side: all domestic taxable persons, including non-VAT payers, must be able to receive Peppol invoices from 1 January 2027.

2. Choose an accredited Digital Postman

You can’t connect directly to the Slovak tax authority. Instead, select an accredited Peppol Service Provider that can:

• Route Peppol BIS 3.0 invoices to and from your trading partners
• Generate and submit the SK TDD to the Financial Administration
• Manage MLS handling, retries and error resolution
• Support the Slovak CIUS v1.8 validation rules
• Meet the 15-minute TDD and 10-minute MLS SLAs

3. Map your ERP to Peppol BIS 3.0

Your ERP will need to output data that can be translated into the Slovak CIUS. Typical work to achieve this includes:

• Mapping master data, tax codes and payment terms to the Peppol semantic model
• Configuring the right document type codes for invoices (380), credit notes (381), corrective invoices (384) and other relevant types
• Ensuring the buyer’s DIČ is captured with scheme 0245
• Reviewing PDF generation, since the human-readable rendering must match the structured XML

4. Design your credit and correction workflow

Because the tax authority is notified in near real-time, invoices can’t simply be deleted once transmitted. Errors must be resolved through structured credit notes or corrective invoices, sent through Peppol and reflected in the SK TDD. Building this workflow into your finance processes early avoids painful workarounds later.

5. Plan customer onboarding

Slovak Peppol onboarding involves a mandatory step by the customer: logging into the national e-invoicing portal, submitting company details and DIČ, and formally selecting a Digital Postman. Only then can the provider register the customer in the centralised Slovak SMP. Building customer awareness of this step is essential to hit the 2027 deadline.

6. Test end-to-end

Use 2026 for end-to-end testing across ERP, integration layer, Peppol Service Provider and business processes. This includes:

• Positive test cases for standard invoices and credit notes
• Negative test cases for rejected invoices and failed TDDs
• Timing tests to validate the 15-minute and 10-minute SLAs
• Business continuity scenarios in case of network or portal issues

Scaling beyond Slovakia: global tax compliance

Slovakia is only one piece of a much bigger puzzle. Across Europe, Latin America, the Middle East and APAC, tax authorities are moving towards structured e-invoicing and continuous transaction controls (CTC). For multinational businesses, meeting each country’s requirements with a separate local provider quickly becomes unmanageable.

This is where global e-invoicing compliance matters. Instead of stitching together point solutions for Slovakia, Germany, France, Spain, the UAE and beyond, businesses are increasingly looking for one integrated platform that can:

• Cover all mandated countries with a single connection to their ERP
• Handle both Peppol-based and non-Peppol models such as clearance, e-reporting and 5-corner architectures
• Keep pace with evolving mandates such as ViDA, France’s e-invoicing reform, and new APAC and LATAM rules
• Provide a single monitoring, archiving and reporting layer across all jurisdictions
• Support standardised customer, supplier and partner onboarding at scale

A local Slovak point solution may cover the January 2027 deadline, but it’s unlikely to scale to the wider European mandate wave or to non-EU markets. A global vendor with a strong local footprint gives you both compliance depth in Slovakia and resilience for future mandates.

How ecosio supports e-invoicing in Slovakia

ecosio is a leading authority on global e-invoicing mandates, with deep expertise in Peppol-based frameworks and country-specific requirements. For Slovakia, we’re building an end-to-end solution that covers the full five-corner model.

With ecosio, businesses can:

• Connect once through their existing ERP and cover all Slovak requirements
• Have invoices automatically translated into Peppol BIS 3.0 with Slovak CIUS
• Have the SK TDD generated and submitted to the Financial Administration within the required 15-minute window
• Manage MLS receipts, retries, resubmissions and disregard flows without manual intervention
• Archive invoices, TDDs and MLS receipts for the full 10-year (or 20-year) retention period

Because we run a single global platform, the same connection also covers France, Germany, Italy, Spain, the UAE, Singapore and many other mandates, so your Slovakia project becomes a stepping stone to a wider compliance strategy, rather than a one-off implementation.

Ready to talk about e-invoicing in Slovakia?

If you’d like to understand the Slovakia e-invoicing mandate in depth and how it applies to your business, get in touch with our team. We’d be more than happy to talk through your options and share what we’re doing for other multinational customers.

Stay informed

Slovakia is only one of many mandates on the horizon. To stay ahead of changes across Europe and beyond, we invite you to make use of our most popular resources:

• E-invoicing updates newsletter: regular briefings on new and updated mandates
• Slovakia compliance overview page: a focused summary of current Slovakian e-invoicing rules
• E-invoicing deadlines calendar: a single view of upcoming mandates worldwide