Slovakia’s E-Invoicing Rollout and Project Athena Tax Compliance Initiative

• Slovakia plans mandatory domestic e-invoicing from 1 January 2027, with 2026 used for preparation, testing, and selecting the “digital postman.”
• Since June 2026, businesses can voluntarily join and exchange structured XML e-invoices in a live environment; once joined, they cannot opt out.
• Companies should carefully verify their e-invoice provider’s PEPPOL certification and Slovak accreditation, and test systems early.
• Project Athena is a new Slovak initiative that will analyze e-invoice data to improve tax compliance and collection.
• Athena aims to reduce tax fraud, narrow the tax gap, improve audit targeting, detect non-compliance, and may later support oversight of taxes beyond VAT.

Source: taxand.com

Note that this post was (partially) written with the help of AI. It is always useful to review the original source material, and where needed to obtain (local) advice from a specialist.

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