Slovakia's next step: A 5-corner model for e-invoicing in 2027

This article was last updated on April 30, 2026, following the publication of the Financial Directorate’s updated FAQs.

Following the final approval of the legislation by the National Council (Parliament) on December 9, 2025, and its subsequent publication on December 19, 2025, Slovakia has secured the implementation of mandatory business-to-business (B2B) electronic invoicing and reporting by January 1, 2027, marking a significant stride in its digital tax transformation. These regulations, which clarify the legislative intent of the approved VAT Act amendments, were officially detailed by the Financial Directorate of the Slovak Republic in their recently updated and expanded Frequently Asked Questions (FAQ) publication 9/VAT/2025/IM (April 2026). As part of a broader European effort to combat tax fraud, the country is preparing to adopt a model with near-real-time electronic reporting, similar to the Peppol-based “5-corner model”.

Building on our previous blog post that provided an overview of the Slovakian government's real-time VAT reporting plan, this article explores the latest legislative developments and their implications for businesses operating within Slovakia, summarising the most recent updates to this crucial process.

Slovakia’s e-invoicing journey continues

As we’ve covered in our previous blog post, Slovakia’s progress on e-invoicing has, until recently, been steady, but cautious:

• B2G and G2G foundations: From April 2023 onwards, Slovakia began introducing mandatory e-invoicing for business-to-government (B2G) and government-to-government (G2G) transactions. The country aligned itself with EU-wide best practice, initially using the IS EFA (Informačný Systém Elektronickej Fakturácie) platform and the European EN 16931 standard. The EFA proposal, however, was cancelled in 2024. Instead, B2G e-invoices will be distributed via the Peppol network in the same way as B2B transactions, from issuer to recipient.

• B2B delays: A voluntary business-to-business (B2B) framework was planned for January 2022, with mandatory obligations expected to follow shortly afterwards. However, by early 2024, these plans had been postponed indefinitely, reflecting the complexity of implementation and the need for a more measured approach.

These developments fit squarely within the continent-wide push to tackle the VAT gap and streamline compliance, echoing initiatives such as the EU’s VAT in the Digital Age (ViDA). Despite setbacks, Slovakia has consistently signalled its determination to modernise tax administration.

The next pivotal step in this evolution was a public consultation on a draft law amending the VAT Act. This consultation, which closed on August 19, 2025, aimed to introduce mandatory e-invoicing and online reporting. This would directly address the previously undefined B2B mandate and set the stage for Slovakia’s expanded e-invoicing obligations.

Public consultation concludes: Mandatory e-invoicing by 2027

In August 2025, the Slovak Ministry of Finance concluded the feedback period for Draft Law No. LP/2025/396, which is a key part of the consultation process. The draft proposes the introduction of mandatory structured e-invoicing and near real-time reporting for domestic B2B transactions, which are set to begin on January 1, 2027.

Following the public consultation, the draft law amending the VAT Act has now been officially approved by the National Council (Parliament) on December 9, 2025, and Law 385/2025 Z.z. published ten days later, on December 19, 2025, completing the legislative process. This decisive step confirms the introduction of mandatory structured e-invoicing and near real-time reporting for domestic B2B transactions, set to begin on January 1, 2027.

As a key deliverable of the ViDA initiative, it highlights Slovakia's commitment to modernising tax administration and improving compliance across Europe. Based on these public consultations and the enacted legislation, Slovakia has confirmed that the requirements will include near-real-time e-reporting to the tax authorities as part of a “5-corner” model, leveraging the international Peppol network.

Peppol’s five-corner model

By adopting a five-corner model for e-invoicing, Slovakia is embracing a modern approach to digital tax administration. Under this framework, businesses exchange electronic invoices via certified Accredited Service Providers (ASPs, also known as “Digitálni poštári” or “Digital Postman”). These ASPs play a crucial role in validating and reporting invoices to the tax authorities.

Unlike some pre-clearance models, where validation occurs before an invoice reaches the buyer, the Slovak system allows invoices to be exchanged freely after validation by an accredited provider. This streamlined process ensures compliance while facilitating efficient business-to-business transactions within a secure network. No recipient consent is required for e-invoicing in Slovakia, as it is a key element of the mandate's implementation.

The mandate’s core obligations

As mentioned previously, this reform introduces two primary obligations for all domestic B2B transactions between VAT-registered businesses: structured e-invoicing and near real-time e-reporting. These requirements are a key deliverable of the ViDA initiative, meaning that, from 2027 onwards, all invoices issued or received in Slovakia must adhere to a predefined electronic format in line with the European Norm. Until June 30, 2030, the invoicing deadline remains 15 days. Furthermore, critical invoice data will need to be reported to the tax authority almost immediately upon issuance. Reporting for received invoices must happen no later than 5 days from receipt.

The introduction of e-reporting will also lead to the abolition of the Control and Summary Statements from July 1, 2030. From the same date, the general invoice issuance deadline is reduced to 10 days.

As detailed above, this system will be supported by the secure Peppol network, enabling businesses to securely exchange invoices via certified third-party service providers. Although Peppol adoption varies across other EU countries, Slovakia's implementation demonstrates its commitment to standardised, efficient digital exchange. To comply with these new regulations, businesses will need to contract with an accredited Peppol service provider (“Digital Postman”) for invoice exchange and tax reporting. Non-compliance with the new reporting obligations can result in penalties of up to € 10,000, or up to € 100,000 for repeated violations.

Crucial exceptions: No fine will be issued where an obvious error is identified and corrected promptly. Similarly, no fine will be issued if it can be proven beyond a doubt that the accredited service provider experienced a failure and reported the data without delay following the issue’s resolution.

Official clarifications and requirements (Financial Directorate FAQ)

These requirements, which were clarified by the Financial Directorate's FAQ prior to the final parliamentary approval, now form the governing rules for the new mandate:

• Mandate scope: From January 1, 2027, the mandatory e-invoicing obligation applies to VAT payers for domestic B2B transactions, excluding B2C invoicing, supplies to the Slovak Information Service or Military Intelligence, deliveries involving classified information, VAT-exempt transactions (e.g., insurance, financial services), simplified invoices, and supplies by foreign VAT-registered persons.

• Format and technology: The e-invoice must be a structured XML format (EN 16931 UBL), which is distinct from a standard PDF. This format complies with Peppol Code Lists v9.5 (December 23, 2025), which defines the identifier scheme 0245 – SG:DIC for a ten-digit Slovak Tax Identification Number (DIČ). The DIČ, issued by the Financial Administration of the Slovak Republic, serves as the national unique identifier and is used for identifying e-invoice recipients in the Peppol network, including cases involving public administration bodies or other legal persons without a VAT number. When registering Slovak end users on the Peppol network, this scheme 0245 can be used to specify the recipient entity’s DIČ.

• Service providers: The exchange will be facilitated by Accredited Service Providers, referred to in the FAQs as “Digitálni poštári” (“digital postmen”), who ensure the secure transmission and real-time reporting to the tax authority.

• Recipient obligation: All legal entities and taxable persons (including entrepreneurs, freelancers, etc.) must be capable of receiving e-invoices via a contracted “Digitálny poštár” service. If a recipient fails to do so, the sender's obligation is considered fulfilled once the invoice has been sent through the delivery service, even if transmission results in an error.

• Integration timeline: A voluntary transition period is scheduled from January 1, 2026, to January 1, 2027, allowing businesses to test their systems. Digital reporting of e-invoice data is expected to become available in Q3 2026 following the establishment of the tax authorities' SP or corner 5 (C5).

• International ambition: Cross-border e-invoicing is not covered by the 2027 mandate but is planned for 2030 in line with the EU's ViDA initiative.

Practical scenarios: corrections and self-billing

Building on practical learnings from other countries with recent mandates — where self-billing arrangements challenged Belgium's implementation and corrective invoice procedures tested Poland's KSeF rollout — the Slovak authorities have proactively addressed these operational scenarios, providing clear rules for corrections and self-billing via certified Digital Postmen.

• Corrective invoices: The Financial Directorate's FAQ clarifies two possible methods for fixing an error after an invoice is sent via Peppol. Simple file edits are strictly forbidden - instead, the sender must create formal corrections with proper audit trails using Peppol document type codes.
  1. The most common, and recommended, method is to issue a credit note (with document type code 381) against the original invoice, then send a new corrected invoice (type code 380). This creates the cleanest account trail and is preferred by most providers.
  2. Alternatively, you may also send a single corrective invoice (“Opravná faktúra”, type code 384) that references the original invoice ID. This must be a new structured Peppol message, not an edit of the original file. Without the proper reference, the tax authority's system will automatically reject it.

• Self-billing (“samofakturácia”): Self-billing lets the buyer issue the invoice on behalf of the supplier. This is common practise in outsourcing, retail chains, or fuel cards, where the customer knows volumes and wants to streamline reconciliation. Slovakia's FAQ confirms these arrangements remain fully permitted, with the same legal requirements as today, i.e., a written agreement between supplier and buyer. However, with the move to e-invoicing, the following digital reporting requirements apply:
  1. Who reports? The buyer (acting as issuer) handles digital reporting to the Financial Administration, even though it's the supplier's sale.
  2. When is it "reported"? The obligation is fulfilled the moment the invoice reaches your certified Digital Postman via Peppol. There is no need to wait for government acknowledgement.
  3. Technical requirements: Self-billed e-invoices follow Peppol BIS Billing 3.0 using type code 389. Both parties need valid Peppol IDs.

Key operational rules

To support the successful exchange and reporting of structured electronic invoices, the latest FAQ guidance includes several critical technical specifications that define the requirements for the e-invoice file format, its display, and its retention.

• Instant human-readable display: While XML is the legal invoice, taxpayers must ensure that their software (such as their ERP, accounting software, or their connected Digital Postman portal) can render it to a PDF-like format immediately if a tax auditor requests. However, there is no constant PDF storage required; XML is sufficient.

• Optional PDF attachments: The e-invoice format allows embedding visual PDFs within the XML file. However, the government does not require them, and any PDF delivery remains a private agreement between buyer and seller.

• Reporting responsibility: The issuer’s reporting duty is fulfilled once the XML reaches their certified Digital Postman. They automatically generate the Tax Data Document (TDD) and handle transmission to the government. Any technical delays become their liability, not the taxpayers.

• Archiving requirements: Archiving rules remain unchanged from the VAT Act. Businesses must store the original XML files for 10 years (20 years for real estate transactions). This follows the same timeline as traditional paper invoices.

What this means for businesses

For market participants, the Ministry's activity signals the urgent need to begin considering system integration. Businesses should proactively plan to connect their IT and accounting platforms to certified service providers. These providers will be vital in handling and transmitting the new structured data formats efficiently through the selected network.

For more background on Slovakia’s e-invoicing landscape, we encourage you to read our previous blog post on the topic.