If we join e-invoice testing in 2026, must we continue using it?

Detailed explanation

The only real limitation on reverting to the original method is not the VAT Act, but any contractual terms agreed with a specific provider of a certified delivery service — some providers may have agreed to a fixed-term commitment, for example in exchange for a discounted price or a free invoice quota. It is therefore advisable to check these contractual terms and conditions before participating in the trial, rather than relying solely on the fact that the whole process is ‘merely a technical test’ without any obligations. The current wording of the Act does not explicitly address concerns that active participation in the voluntary phase might later prove disadvantageous (for example, in connection with a possible earlier change to deadlines) — the trial period is merely an opportunity, not an obligation.

As set out in the Act

The voluntary nature of the period from 1 January 2026 to 1 January 2027 stems from the transitional provisions of Section 85o of Act No. 222/2004 Coll. on VAT, as amended by Act No. 385/2025 Coll. The fact that e-invoices sent during this voluntary period are not reported to the Financial Administration and that the VAT control statement continues to be submitted in full is confirmed by the official methodological and information materials of the Financial Administration of the Slovak Republic on e-invoicing.

Practical examples

• The company will trial the system for three months and then decide to temporarily revert to its current invoicing method until 2027.
• Before joining the trial, the company will check whether its contract with the provider contains any binding clauses preventing an earlier withdrawal.
• Returning to the original invoicing method before 2027 does not in itself constitute a breach of the VAT Act.

Most common mistakes

• “Participation in the pilot scheme in 2026 entails an obligation to continue in it until 2027.” The Act describes this period as voluntary, with no obligation to remain in it.
• “The risk involved in reverting to the original method is always purely technical.” The real risk lies rather in any contractual terms with the provider, not directly in the VAT Act.
• “During the trial period, there is no need to submit a VAT control statement.” In 2026, the VAT control statement will continue to be submitted in full, regardless of the trial operation.

Conclusion

Voluntary testing in 2026 does not create a statutory obligation to continue; only the selected provider’s contractual terms may affect withdrawal from its service.

Legal basis

• Act No. 222/2004 Coll. on VAT, Section 85o (as amended by Act No. 385/2025 Coll.)
• Official methodological and information materials Financial Administration of the Slovak Republic k e-invoice

Related questions

• Are e-invoices from the trial period reported to the Financial Administration?
• What should you look out for in a courier’s terms and conditions?
• What is the grace period in 2027?

This is not legal advice. Sources: Act No. 222/2004 Coll. on VAT, as amended by Act No. 385/2025 Coll., official methodological and information materials from the Slovak Financial Administration on e-invoices, the Peppol network operating rules (OpenPeppol) and the Peppol Authority Specific Requirements for the Slovak Republic. Verified on 7 July 2026.