Mandatory e-Invoice Exchange Starting in 2028

The new framework, which takes effect on 1 January 2028, aims to streamline business processes and reduce operational costs. Electronic invoices have been part of the public sector for many years — they became mandatory for budget users in 2015 and entered the public procurement system in 2019. Their use has steadily increased; the number of e-invoices issued within the public sector rose from 461,000 in 2015 to nearly 2.2 million in 2024. Companies are adopting them as well — in 2022, approximately 60% of businesses with at least 10 employees were already sending e-invoices.

From 2028 onward, e-invoice exchange will be mandatory for all entities registered in the Business Register of Slovenia, including sole proprietors. Paper invoices will no longer be permitted in business-to-business transactions, although they may still be used when dealing with consumers or foreign companies. For consumers, nothing changes — they may continue to receive paper invoices unless they agree otherwise with the supplier.

An electronic invoice is a structured XML document that enables fully automated data processing. Exchange will take place through secure electronic channels, including e-delivery service providers, direct system-to-system connections, the PEPPOL network, or the free miniBlagajna application. Sending invoices via email will no longer be allowed in B2B transactions.

The new regulation brings numerous benefits — from improved transparency and fewer errors to lower costs and a positive environmental impact. Many European countries have already introduced similar systems or are in the process of doing so, placing Slovenia firmly within the broader trend of business digitalisation.

The law also lays the groundwork for upcoming EU legislation, which will require mandatory cross-border e-invoice exchange by 2030.