Guides · · 4 min read

Invoicing Slovakia 2026: reverse charge step by step

How to invoice a Slovak client: reverse charge, the identified-person duty for non-VAT payers, checking the VAT number in VIES, and invoicing in euros.

Slovakia is the most natural export market for a Czech OSVČ (sole trader): no language barrier, culturally close clients. The first invoice to a Slovak client still catches people out, though — suddenly there is reverse charge, VIES, the identified person and euros to deal with. The good news is that once the logic clicks, it is routine.

Two questions that decide everything

  1. Are you invoicing a company or a business (B2B), or an end consumer (B2C)?
  2. Are you registered for DPH (Czech VAT), not registered, or an identified person?

The overwhelming majority of cases are B2B services, and the rule there is simple: the place of supply is in Slovakia and your customer accounts for the VAT under the reverse charge mechanism. You invoice without VAT.

Scenario 1: you are registered for VAT

Issue the invoice without tax and add the mandatory clause "daň odvede zákazník" (the customer accounts for the tax). The invoice must carry your DIČ (tax ID) and the customer's Slovak VAT number (IČ DPH) — and you should check that number in the EU register VIES before you invoice. You then report the supply on line 21 of your VAT return and in the EC Sales List (souhrnné hlášení) under code 3.

⚠️ Without proof that the customer is a business, reverse charge is not a given. A missing VIES record does not by itself mean you must charge Czech VAT: a Slovak business with no VAT number is still a taxable person and the place of supply stays in Slovakia, provided you can show its business status another way (Article 18 of Council Regulation 282/2011 — for example a Slovak company ID or a register extract). Only if the customer cannot show it is in business does the supply count as B2C for VAT purposes, and as a Czech VAT payer you charge Czech VAT at 21%. Checking VIES is therefore not a formality, it is your insurance against an assessment later.

Scenario 2: you are not registered for VAT

This is where the most common mistake hides. By supplying a service to a business in another EU country you do not become a VAT payer, but you must register as an identified person — electronically, within 15 days of the date the service was supplied. From that point on:

  • you invoice Slovak businesses without VAT under reverse charge, exactly as a VAT payer would;
  • for every month in which you supplied a service to the EU, you file an EC Sales List;
  • domestically you stay a non-payer — you keep invoicing Czech clients without VAT and you have no right to deduct input tax.

The whole process is covered in our guide to the identified person for VAT. Registering is not optional: it is a statutory duty, and missing it carries a penalty.

Scenario 3: invoicing a consumer (B2C)

For ordinary services to an end consumer in Slovakia the place of supply is in Czechia: a VAT payer charges Czech VAT, a non-payer invoices without tax and the income counts towards the turnover for the mandatory VAT registration threshold. Exceptions — electronically supplied services and goods sold through an e-shop — have their own rules and the OSS scheme; there is more on that in Invoicing a foreign client from Czechia.

What the invoice has to contain

ItemNote
Your details and your DIČAn identified person uses the DIČ assigned on registration
The customer's VAT number (SK…)Checked in VIES, ideally with the confirmation saved
"Daň odvede zákazník"A mandatory item under reverse charge
Date of taxable supply (DUZP)It also governs the exchange rate used
Currency and amountEUR is fine — for your records you convert at the ČNB rate
💡 Where Taxorio helps: when you save a client with a Slovak VAT number, the app checks it in VIES automatically and shows you whether it is valid; the AI assistant can run the same check on request. Set the invoice to the EU B2B service regime and the "daň odvede zákazník" clause is printed on the document for you, and the PDF carries your IBAN and SWIFT, so the Slovak client can pay without asking for details.

A few practical points

  • Invoice in euros if that is what the client prefers. Slovak companies pay in EUR and an invoice in Czech crowns is an inconvenience for them. The conversion is your problem, not theirs.
  • Due date and IBAN: give the account as IBAN plus BIC, ideally a euro account, so the client is not paying for an expensive conversion.
  • Keep the VIES check from the invoicing date. During an inspection it is how you show the VAT number was valid at the time.

In short

An invoice to Slovakia is the simplest "foreign" invoice you will ever issue: a B2B service means reverse charge without VAT, the clause "daň odvede zákazník", a VAT number verified in VIES and an entry in the EC Sales List. Non-payers only have to watch the 15-day deadline for registering as an identified person — and leave the VIES check to their invoicing software.

Taxorio scope: Taxorio provides invoicing and income/expense records for Czech sole traders. It is not full accounting or personalised tax advice. For an unsupported or unusual case, verify the treatment with a Czech accountant or tax adviser before filing.

Frequently asked questions

I am not registered for VAT — does invoicing Slovakia change anything for me?
Yes. Supplying a service to a Slovak business triggers a duty to register as an identified person for VAT within 15 days. You then invoice without VAT under reverse charge and file an EC Sales List for the months concerned. Domestically you remain a non-payer.
What wording must appear on a reverse charge invoice?
The mandatory item is the clause "daň odvede zákazník" — the customer accounts for the tax. The invoice must also show your DIČ and the customer's valid Slovak VAT number. No VAT amount is stated; the customer declares the tax in Slovakia.
What if the Slovak client has no VAT number?
A missing VAT number does not automatically mean Czech VAT. If the client is demonstrably in business (shown other than through VIES — a Slovak company ID or a register extract, say), the place of supply stays in Slovakia and you invoice without VAT. If business status cannot be shown, it is a supply to a non-business: as a VAT payer you charge Czech VAT at 21%; as a non-payer you invoice without tax and the income counts towards the turnover for mandatory VAT registration.
Can I issue an invoice to Slovakia in euros?
Yes. The law does not prescribe the currency of an invoice, and Slovak clients appreciate euros. For your Czech tax records, though, you convert the amount into crowns at the ČNB rate on the date of taxable supply, and VAT is always reported in crowns.
When is the EC Sales List due when invoicing Slovakia?
For every calendar month in which you supplied a reverse charge service to a business in another EU country, within 25 days of the end of that month. A quarterly VAT payer who supplies only services to the EU files the EC Sales List quarterly. The duty applies to VAT payers and identified persons alike.