The Mandatory Invoice Components of 2026
As a business owner, freelancer, or entrepreneur in Slovenia, mastering the art of invoicing is non-negotiable. An incorrect invoice doesn't just delay your payments; it can also trigger steep fines during a Financial Administration (FURS) audit.
Here is your definitive, up-to-date guide on Slovenian invoicing requirements for 2026, including the latest legislative updates you need to know.
The 2026 E-Invoicing Update: Where Do We Stand?
While Slovenia passed the Act on Electronic Invoicing (ZIERDED) to mandate structured B2B e-invoices (XML format via the e-Slog standard), the mandatory rollout for private B2B transactions has been officially postponed until January 1, 2028. This means that throughout 2026, standard paper or PDF invoices remain perfectly legal for standard B2B and B2C transactions, provided they contain all legally required elements. Structured e-invoices remain mandatory only if you are invoicing government entities, known as B2G transactions.
- Standard B2B Invoice
If you are issuing a full Value Added Tax (VAT) invoice to another business or legal entity, the Slovenian Value Added Tax Act (ZDDV-1) and Slovene Accounting Standards require the following components:
- Invoice Date: The exact calendar day the invoice is issued. Sequential Number: A unique, consecutive number from an uninterrupted sequence that clearly identifies the invoice for audit tracking.
- Supplier Details: Your full company name, registered business address, and VAT identification number (prefixed with "SI" if you are VAT-registered).
- Customer Details: The recipient’s full business name, registered address, and their VAT ID (mandatory if they are liable for the VAT or for cross-border EU transactions).
- Supply Date: The date the goods were delivered or the services were fully rendered. If this matches the invoice date, it must still be clearly stated or implied.
- Description of Supply: The exact quantity and nature of the goods supplied, or the specific scope of the services provided.
- Financial Breakdown: The taxable net amount (before VAT) / The unit price exclusive of VAT / Any discounts, rebates, or price reductions not already calculated into the unit price.
- VAT Details: The specific VAT rate applied (the standard 22% or reduced 9.5% / 5%) and the final total VAT amount payable, explicitly stated in Euros.
Mandatory Clauses You Must Include
Depending on your tax status and transaction type, you are legally required to append specific text clauses at the bottom of your invoice. Leaving these out makes the invoice non-compliant.
- Standard B2C Invoice
Because everyday consumers do not claim input VAT returns, Slovenian tax law allows B2C transactions to use the simplified invoice structure (or cash register receipts issued via a certified fiscal cashier / davčna blagajna).
To be compliant, a B2C invoice must include:
- Invoice Date & Consecutive Number
- Seller Details: Business name, address, and VAT ID
- Description: Quantities and nature of goods or services provided
- Total Payable Amount: The total price including VAT
- VAT Information: The applicable VAT rate (e.g., 22%, 9.5%) or the specific tax amount
If a business customer intends to use a simplified invoice to deduct input VAT, their business name, address, and VAT ID must still be manually added to the document.
Stop Worrying About Compliance — Let Apollo Handle It
Manually tracking sequential numbers, calculating partial VAT rates, and remembering complex legal phrases is a recipe for administrative burnout. With Apollo, compliance is entirely automated. Whether you are a small freelancer exempt from VAT or a growing enterprise handling international reverse charges, Apollo dynamically builds compliant invoices tailored to Slovenian law.
