The Slovak administration presents e-Faktúra as a change to invoice transmission from 1 January 2027, without replacing accounting principles. A structured invoice is more than sending a PDF reproducing a paper document.
A particular operational issue is error handling: an invoice already sent must not simply be overwritten in the system. Correction requires an amending document, itself electronic where the original invoice falls within that process. The transaction's history must therefore remain understandable.
Useful preparation consists of examining how an error is handled after transmission, not just how a correct invoice is created. The correcting document must be linkable to the original transaction, and the data ultimately retained in the accounts understandable. A business combining sales to businesses and consumers must also distinguish its transaction flows. The announcement informs these arrangements without permitting uniform treatment of transactions it itself places in different scopes.
The announcement also specifies that ordinary sales to consumers do not fall within this obligation. A business must therefore distinguish its affected flows before changing invoice issuance. Adopting compatible software removes neither the need to classify the transaction nor to comply with the tax and accounting rules that continue to apply.