How Slovak e-invoicing works, in plain words

In Slovakia you don't upload invoices to a government portal, and the state doesn't run a central invoice platform. You hand the invoice to your certified provider (the "digital postman"). It delivers the invoice over the Peppol network to your customer's provider, and both providers report the invoice data to the Financial Administration ^[1][2]. OpenPeppol and the Financial Administration call this a decentralised 5-corner model ^[1].

The five corners

Corner	Who	What they do
1	You, the supplier	Create the invoice in your invoicing or accounting software, or in your provider's web app
2	Your digital postman	Checks the format, sends the invoice over Peppol, and sends the tax data to the Financial Administration [1][2]
3	Your customer's digital postman	Receives the invoice and reports the tax data for VAT-payer customers [1][2]
4	Your customer	Gets the invoice in its software or web mailbox
5	The Financial Administration	Receives the tax data from both sides [1]

Steps 1 to 4 are the normal Peppol "four corners" used across Europe. Corner 5 is the Slovak addition ^[1].

What travels where

• The invoice goes from corner 2 to corner 3 as a Peppol BIS Billing 3.0 file (UBL XML) ^[1].
• The tax data goes to the Financial Administration as a separate, smaller file, the Tax Data Document (TDD), also over Peppol ^[1][4]. It carries the invoice data that the VAT Act lists: VAT numbers, invoice number and dates, amounts and VAT ^[2].
• Timing. The supplier's data is reported when the invoice is issued; for a self-billing invoice, within 5 days. A VAT-payer customer reports within 5 days of receiving. In both cases the duty is met by handing the invoice to the provider ^[2][5].

The digital postman

A certified delivery service provider is a company on the Financial Administration's register ^[2]. To get there it needs a seat in the EU, a clean criminal record for the company and its directors, and OpenPeppol certification for e-invoicing and e-reporting, including the Slovak tests ^[3][4]. By law its service must [2]:

• check the e-invoice's format automatically;
• identify the sender and the recipient reliably;
• keep the invoice authentic, intact and readable from sending to delivery;
• prove the date and time of sending, delivery and receipt;
• report the data to the Financial Administration automatically.

You can use a provider directly, through its web or mobile app, or through your accounting software, which may itself be a provider or an intermediary reselling one ^[3][6]. Providers set their own prices ^[3]. See the list of certified providers.

Addresses: the DIČ and the central register

Every Slovak business on the network is addressed by 0245: plus its DIČ ^[4]. All Slovak businesses sit in one central address register (SMP) ^[4]. You choose your provider on the Financial Administration portal; the portal gives the provider a token that lets it register you, and you then sign a contract with it ^[1][5]. You can have one provider for receiving and several for sending ^[5]. Look up any business in our Peppol ID lookup.

Do invoices have to go through Peppol?

An e-invoice that a VAT payer must issue goes through a certified provider, unless the customer agrees to another channel (for example email or EDI). The file must still be structured XML under EN 16931; a PDF is not enough ^[2][6]. Invoices sent another way are not reported automatically, so the existing VAT control statement still covers them ^[5][6]. Everyone who must receive e-invoices needs a provider anyway ^[6].

Timeline

Date	What happens
1 January 2026	Act 385/2025 valid; the register of certified providers opens; voluntary e-invoicing [3][5][7]
15 December 2026	Providers registered in 2026 must have shown that their reporting works, or they are removed on 1 January 2027 [2]
1 January 2027	Mandatory domestic B2B and B2G e-invoicing; every business must be able to receive [2][3]
30 June 2030	End of the transitional domestic rules (§ 85o) [2]
1 July 2030	Cross-border e-invoicing planned (EU ViDA); VAT control statement and EC sales list abolished; invoice deadline 10 days [5][6]

Wondering what applies to you? Use the obligation checker.

Information, not legal or tax advice. The official texts are in Slovak; translations are ours. Checked on 9 October 2026.