E-invoicing from 1 January 2027: a practical guide for companies and sole traders

From 1 January 2027, the way companies send invoices to each other in Slovakia is changing. The amendment to the VAT Act (zákon č. 385/2025 Z. z.) introduces mandatory electronic invoicing. A PDF sent by email will no longer be sufficient for domestic transactions between companies. We have summarised what this means in practice and what you should prepare.

What an e-invoice is – and what it is not

An e-invoice is not a PDF, a scan, or an invoice in Word. It is a structured XML file according to the European standard EN 16931 (in Slovakia in the Peppol BIS Billing 3.0 format). Accounting software can import it automatically, without retyping.

It is delivered via the Peppol network through a certified provider, which the Financial Administration calls a digital postman. A company’s address in the network is its Peppol ID derived from its DIČ.

Who the obligation applies to

• Issue e-invoices must be issued by VAT payers when supplying goods and services domestically to another company or to the state (B2B and B2G).
• Receive e-invoices must be able to be received by every legal entity and every business, including a non-VAT payer to whom a VAT payer must send an e-invoice.
• It does not apply to invoices for consumers (B2C) or supplies exempt from VAT under § 28 to 42 of the VAT Act.

We have dedicated a separate article to non-VAT payers.

What is not changing

• The deadline for issuing an invoice remains 15 days from the supply (or from receipt of payment).
• The invoice particulars remain the same; only the form and the method of delivery are changing.
• The VAT Control Statement will continue to be filed for the time being. Its abolition is linked only to the second phase (cross-border transactions), which is planned from 1. 7. 2030.

Reporting data to the Financial Administration

Selected data from the e-invoice is reported to the Financial Administration. A recipient who is a VAT payer has 5 days to report the data from a received invoice. In practice, this will be done on their behalf by a digital postman.

For failure to report or for incorrect data, the law allows a fine of up to 10 000 €, and in the event of a repeated breach up to 100 000 €. An obvious mistake that you correct immediately is not fined. The same applies if you can prove that your digital postman failed and you reported the data immediately after the fault was rectified.

The year 2026 is for testing

During 2026, you can join the system voluntarily and try sending e-invoices before it becomes mandatory. The Financial Administration continuously publishes the list of certified digital postmen on its portal.

What to do during 2026

1. Find out whether you are a VAT payer. If you are, from January you will both issue and receive e-invoices. If not, you only need to be able to receive them.
2. Add customers’ Tax ID numbers. A Peppol network address is created from the Tax ID number (0245:Tax ID). Without it, you cannot deliver an e-invoice.
3. Choose a digital postman from the Financial Administration’s list, either separately or through your invoicing software.
4. Check the code lists. Units of measure must come from a list of codes, not free text (for example, “pcs” is mapped to a unit code according to UN/ECE). Good software will do this for you.
5. Try it in practice with one or two customers during the voluntary period.

How we handle it in DSDATA

We can create every invoice, credit note and tax document for an advance payment received as an e-invoice in Peppol BIS 3.0 format. We add VAT categories and exemption reasons according to the document regime and validate the XML against the EN 16931 rules. More on the E-invoice 2027 page.

Sources

• Financial Administration of the Slovak Republic – Frequently asked questions and answers on eInvoice (9/DPH/2025/IM, version dated 11/9/2026)
• Act No. 385/2025 Coll., amending Act No. 222/2004 Coll. on value added tax (Slov-Lex)