E-Invoicing in Slovakia: Rules, Timeline & 2027 Mandatory B2B Guide

E-Invoicing in Slovakia

Slovakia’s Financial Administration (Finančná správa), under planned amendments to the Slovak Value Added Tax Act (Law No. 222/2004) and in line with the European Union’s VAT in the Digital Age (ViDA) initiative, is introducing mandatory electronic invoicing as part of the country’s tax administration digitalisation roadmap. The system is expected to make structured e-invoicing mandatory for VAT-registered businesses, changing how invoices are issued, reported, and validated across Slovakia.

The mandate will require domestic VAT-registered businesses to issue and receive invoices in a structured electronic format for business-to-business and business-to-government transactions once fully enforced. Invoices must be generated and transmitted through certified systems compliant with Slovak e-invoicing standards. Any invoice not issued in the required structured format will not be considered a valid electronic invoice under Slovak law once the mandate becomes effective.

E-invoicing is designed to improve transparency, reduce VAT fraud, and automate record-keeping for both businesses and the Financial Administration. This blog explains the requirements of the system, key timelines, technical process, benefits, and how providers like Flick Network help companies prepare for and comply with the new law.

What Is E-Invoicing in Slovakia

E-invoicing in Slovakia refers to issuing, receiving, validating, and storing invoices electronically in a structured data format rather than purely paper-based or unstructured digital formats. Each invoice is generated by compliant accounting or invoicing software in a structured XML format aligned with the European standard EN 16931 and Slovak technical requirements. It must be capable of transmitting invoice data through approved delivery channels and reporting the data to the Financial Administration once reporting becomes mandatory.

Invoices that are merely scanned copies or unstructured PDF invoices do not qualify as electronic invoices under the planned Slovak e-invoicing framework. Once issued in the required format and transmitted, the business retains the electronic record, making both the supplier and the tax authority able to access and audit the transactions. Certified delivery services or compliant third-party software enable businesses to generate, send, receive, and track invoices automatically. The process reduces manual paperwork, improves data accuracy, and ensures traceability across business transactions in Slovakia.

Slovakia E-Invoicing Timeline and Important Dates

The rollout of e-invoicing in Slovakia is planned to be phased, giving businesses time to prepare before full enforcement.

• 1 January 2026: Voluntary phase began, allowing businesses to issue and receive structured electronic invoices and test their systems.

• 1 January 2027: Mandatory structured e-invoicing and near real-time invoice data reporting is planned to become effective for domestic B2B and B2G transactions for VAT-registered businesses established in Slovakia.

• 1 July 2030: The obligation is expected to expand to cross-border intra-EU transactions, in line with the EU ViDA framework, with e-reporting replacing existing VAT control statements and EC Sales Lists.

Who Must Follow Slovakia’s E-Invoicing Rules

The Slovak e-invoicing mandate is expected to cover the following taxpayers:

• All VAT-registered entities existing in the Slovak Republic, such as companies, sole proprietorships, freelancers, and professionals.

• VAT-registered companies which issue invoices to other VAT-registered companies in the case of B2B, B2G sales.

• Companies will be obliged to be able to accept structured electronic invoices and to meet obligations to report invoice data.

• Business transactions with consumers are currently beyond the compulsory jurisdiction.

Technical Rules and E-Invoicing Process in Slovakia

These are the primary technical requirements and points in the process in the proposed mandate:

• Format of the Invoice: The invoices should be generated in a specific XML structure following the EN 16931 standard and the Slovak technical specification; so that the data present in the invoices can be extracted and processed automatically.

• Certified Software or Delivery Service: Businesses are required to use the certified accounting or invoicing software or access the certified e-invoicing service provider with the ability to provide structured invoices.

• Invoice Data Transmission: Invoices shall be transmitted electronically via authorized delivery services. Reporting of invoice data to the Financial Administration should be done in close to real time after enforcement has started.

• Archiving and Record Keeping: For businesses, there must be the ability to store electronic invoices and data in retrievable form in an electronic archive.

• Data Integrity: The system should provide a mechanism to ensure that data transfer and data integrity on invoices are secured. That is, a defined structure enables traceability.

Benefits of E-Invoicing in Slovakia

E-invoicing in Slovakia combines regulatory and operational benefits for businesses and the tax authority:

• Efficiency: There will be automation in the generation, distribution, and generation of reports regarding invoices.

• Accuracy: This is achieved since organized information on invoices facilitates accuracy in VAT computation and submission.

• Compliance: The near real-time access to the invoice information improves VAT control and compliance in the Financial Administration.

• Cost Savings: There is a reduced need to print paper invoices and store files, thus lowering printing, file storage, and audit preparation costs.

• Fraud Prevention : Structured e-invoicing minimises the risk of unauthorised invoice changes and VAT fraud by ensuring traceability throughout the invoicing process.

• Quick Reconciliation: The reconciliation process is also faster as a result of automation.

Consequences for Failing to Comply with E-Invoicing in Slovakia

Non-compliance with Slovakia’s e-invoicing requirements may create several risks for a business once the mandate is enforced:

• Invalid Invoices: Invoices not issued in the required structured format may not be considered valid for VAT purposes.

• Penalties: Failure to comply with reporting or technical requirements may lead to administrative fines or sanctions under Slovak tax law.

• Operational Disruptions: Delayed system integration or technical issues may disrupt billing and reporting workflows.

• Audit Risk: Non-standard or non-structured invoices may increase scrutiny during tax audits.

How to Prepare for E-Invoicing in Slovakia

Here are steps businesses should take now to prepare:

• Assess Your Systems: Review whether your accounting ERP or billing systems can generate, receive and archive structured electronic invoices. Ensure the systems can handle invoice data transmission and storage in compliance with Slovak technical requirements.

• Choose a Solution Provider: Partner with a compliance-ready provider such as Flick Network for structured invoice generation - transmission - reporting and secure archiving of all electronic invoices.

• Integrate and Test: Connect your systems through approved delivery services or APIs and test invoice issuance receipt and reporting processes before mandatory enforcement begins.

• Staff Training: Train finance and accounting teams on the structured e-invoicing process, reporting obligations and the management of digital invoice records to ensure smooth compliance and operational efficiency.

How Flick Network Helps Businesses with E-Invoicing in Slovakia

Flick Network provides a compliance-driven invoicing platform tailored for businesses of all sizes and jurisdictions. For Slovakia, the platform supports the transition to structured e-invoicing by offering:

• Structured Invoice Generation: Flick Network formats invoices in structured XML formats aligned with Slovak and EU e-invoicing standards.

• Submission and Reporting: The platform supports secure invoice transmission and preparation for near real-time reporting to the Financial Administration.

• Invoice Archiving and Tracking: All invoices and transmission logs are stored digitally with full traceability for audits and compliance monitoring.

• Integration with ERP and Billing Systems: Flick Network integrates with existing accounting and billing systems, reducing manual work and standardising invoice workflows.

• Continuous Compliance Support: Ongoing regulatory monitoring, technical updates, and onboarding assistance help ensure continued alignment with Slovak requirements.

Conclusion

Slovakia’s planned transition to mandatory structured e-invoicing from 1 January 2027 represents a major step in modernising tax compliance and business operations. From this date, VAT-registered businesses will be required to issue, receive, and report invoices in a structured electronic format through compliant systems.

By preparing early, integrating compliant solutions, training teams, and maintaining proper digital archives, businesses can streamline operations, reduce errors, and remain fully compliant. Solutions like Flick Network help simplify the transition by supporting invoice generation, transmission, archiving, and compliance processes end-to-end, enabling a smooth shift to fully digital invoicing in Slovakia.

FAQs

1. What is Slovakia’s e-invoicing system?
   It is a national framework for issuing and exchanging structured electronic invoices that support automated processing and VAT compliance.

2. Who must comply with the e-invoicing mandate in Slovakia?
   VAT-registered businesses involved in domestic B2B and B2G transactions will be required to comply once mandatory enforcement begins.

3. What happens if a business issues a PDF invoice in Slovakia?
   A standard PDF invoice does not qualify as a structured electronic invoice under the planned Slovak e-invoicing framework.

4. Is invoice data reporting mandatory?
   Yes. Structured invoice data reporting to the Financial Administration is expected to be mandatory once the system is fully enforced.

5. How long must e-invoices be stored?
   Electronic invoices must be archived in a retrievable digital format and made available for audit and compliance purposes in line with Slovak record-keeping rules.