Invoice requirements in Slovakia 2026: what a sole trader's invoice must contain

Invoices are among the documents a sole trader issues most often, and a mistake in one can come back during a tax audit or when the customer deducts VAT. This guide covers what an invoice must contain under the Slovak VAT Act, what applies to non-VAT payers, and how to handle numbering, due dates, foreign currencies and corrections. It describes the rules in force in 2026; the changes from 2027 are summed up at the end.

VAT payer or not?

The answer decides which rules apply to your invoice. A business with its seat, place of business or residence in Slovakia must become a VAT payer once its turnover for a calendar year exceeds €50,000, starting from 1 January of the following year. If turnover exceeds €62,500 during the year, it becomes a VAT payer with the very supply that crosses that line. Registering voluntarily earlier is also possible.^⁠[1]

A VAT payer must issue an invoice when it supplies goods or services in Slovakia to another taxable person (including a sole trader who is not a VAT payer) or to a legal entity; supplies exempt under § 28 to 42 are the exception. It does not have to issue a VAT invoice to a private individual; for a cash payment, however, it must give them an eKasa cash-register receipt.^⁠[1]⁠[4]

Mandatory details on a VAT payer's invoice

The list of particulars is set by § 74(1) of the VAT Act. For an ordinary domestic invoice these are:^⁠[1]⁠[3]

The date of supply can be left out when it is the same as the date of issue. For a reverse charge the words "prenesenie daňovej povinnosti" are enough; the provision under which it applies does not have to be on the invoice.^⁠[3] When the reverse charge applies to supplies within Slovakia (for example construction work) is covered in Domestic reverse charge in Slovakia.

A non-VAT payer's invoice

A sole trader who is not a VAT payer does not issue a VAT-Act invoice for ordinary sales in Slovakia. The VAT Act requires them to issue an invoice only in special cases, mainly for services with the place of supply in another Member State or a non-EU country.^⁠[1]⁠[5] What the invoice says still matters:

• The Commercial Code requires a business to state on its business documents its business name, seat or place of business and company ID (IČO); if it is entered in the Commercial Register or another register of businesses, also the register and the entry number. These details are routinely shown on invoices too.^⁠[9]
• If you keep accounts, the invoice is an accounting document and must also contain the particulars of § 10 of the Accounting Act: a document designation, what the transaction is and who the parties are, the amount, the date of issue and the date of the transaction if different.^⁠[11]
• Do not state VAT on the invoice; otherwise you will have to pay it.^⁠[1]

We recommend that a non-VAT payer's invoice carries the same details as a VAT payer's, minus the VAT ID, rate and tax amount, and that it says you are not a VAT payer. The customer then has no doubt why there is no VAT on it.

Invoice numbering

Today the VAT Act requires a "sequential invoice number".^⁠[1] From 1 January 2027 the wording becomes more precise: a sequential number based on one or more series that uniquely identifies the invoice.^⁠[2]

• The clearest option is one series per year, for example 2026001, 2026002 and so on.
• From 2027 the Act explicitly allows several series (say, one per establishment) as long as the number identifies the invoice uniquely.^⁠[2]
• Never use a number twice. Do not fix a mistake on an invoice you have sent by overwriting it: issue a corrective invoice that refers to the original number.^⁠[3]

Issuing deadline and due date

A VAT payer must issue the invoice within 15 days of supplying the goods or services. For a payment received before the supply (an advance), within 15 days of receiving it or by the end of the month in which it was received.^⁠[1]⁠[4] Several supplies within one calendar month can be covered by a summary invoice issued within 15 days of the end of the month.^⁠[1]

The VAT Act does not set the due date: you agree it with the customer. Between businesses, however, the contractual payment term may not exceed 60 days from receipt of the invoice or from performance (whichever is later), unless the parties expressly agree on a longer term and the agreement is not grossly unfair to the creditor. Where the debtor is a public-law entity, the term is generally 30 days.^⁠[9]

If the customer pays late, you are entitled, without any further reminder, to late-payment interest (unless agreed otherwise, the ECB main rate valid on the first day of the calendar half-year plus 8 percentage points) and to a flat €40 compensation for recovery costs.^{⁠[9]⁠[10]} What to do when the customer still does not pay after a reminder is covered in Unpaid invoice in Slovakia.

Rounding VAT

Calculated VAT is rounded to the nearest cent: below €0.005 down, from €0.005 up.^⁠[1] For example, a tax base of €123.45 at 23 % gives €28.3935 of VAT, so the invoice shows €28.39.

Foreign currency and foreign language

You can issue an invoice in a currency other than the euro. For VAT purposes, however, the tax base is converted into euros at the ECB or National Bank of Slovakia reference rate valid on the day before the tax point, and the VAT amount on the invoice is stated in euros. Alternatively you may use the customs exchange rate if you notify the tax office in writing in advance; the choice then applies for the whole calendar year.^⁠[1]

The invoice may also be in a foreign language. You only need to provide a Slovak translation when the tax office asks for one for an audit; there is no need to attach it to your invoices.^⁠[1]⁠[8]

Corrective invoices and credit notes

The tax base is corrected when a supply is cancelled or returned in full or in part, when the price is reduced after the tax point (a discount or a complaint, for example) and when it is increased.^⁠[1] The VAT payer then issues a corrective invoice; in practice it is called a dobropis (credit note) when the amount goes down and a ťarchopis (debit note) when it goes up.^⁠[3]

• A corrective invoice must refer unambiguously to the original: it is enough if it states the number of the original invoice and the data that change.^⁠[1]
• It must be issued within 15 days of the end of the calendar month in which the event giving rise to the correction occurred.^⁠[1]⁠[6]
• The supplier reports the difference in the tax base and VAT in the return for the period in which the corrective invoice was issued.^⁠[1]
• Formal errors are corrected with a corrective invoice too, for instance a wrong customer VAT ID.^⁠[3]
• If the customer does not pay, that is not a credit note: correcting the tax base for an unpaid consideration follows a separate procedure, using a corrective document under § 25a that is not an invoice.^⁠[1]

Simplified invoice

For small sales a simplified invoice is enough, without customer details or a unit price: a document for goods or services up to €100 including VAT, or an eKasa cash-register receipt up to €400 including VAT.^⁠[1]⁠[3] A simplified invoice must not be issued for an exempt supply of goods to another Member State, for distance sales of goods, or for supplies in another Member State where the customer pays the VAT.^⁠[1]

How long to keep invoices

A VAT payer keeps copies of issued invoices and the invoices it received for ten years following the year they relate to.^⁠[1]⁠[7] A non-VAT payer keeps mainly the invoices it had to issue under the VAT Act and received invoices on which it had to pay VAT.^⁠[1] If you keep accounts, all accounting documents are kept for ten years as well.^⁠[11]

The form is up to you: paper invoices may be scanned and archived electronically, provided the tax office can access them.^⁠[7] For e-invoices from 2027, archive the structured file itself; see E-invoicing in Slovakia from 1 January 2027. How long and in what form to keep paper and electronic invoices is covered in detail in Keeping invoices in Slovakia.

What changes in 2027 and 2030

• 1 January 2027: VAT payers issue e-invoices for domestic sales to businesses and legal entities, and the numbering rule becomes "one or more series that uniquely identify the invoice".^⁠[2]
• 1 July 2030: the issuing deadline shortens to 10 days, and the bank account number (or another account identifier) to which the invoice can be paid becomes a mandatory detail, as does the original invoice number on corrections.^⁠[2]
• In parliament: an amendment to the VAT Act (print 1454) that further adjusts the e-invoicing rules; it has not been passed as of 11 October 2026.^⁠[12]

Everything about mandatory e-invoicing is in E-invoicing in Slovakia from 1 January 2027, and the network it will travel over is explained in Peppol in practice.

Checklist before you send an invoice

Mandatory details and good habits in one place:

• Supplier's and customer's details including company ID (IČO) and, if you are a VAT payer, both VAT IDs.
• A sequential number with no duplicates.
• Date of issue, and the date of supply if it differs.
• Description, quantity, unit price excluding VAT, and discounts.
• Tax base, rate and VAT amount in euros, or the exemption or reverse-charge wording.
• Due date and payment details: IBAN and variable symbol.
• If you are not a VAT payer: no VAT, and a note saying so.
• A copy of the invoice archived for ten years.

Invoicing in vporiadku

In vporiadku you can issue invoices, advance invoices and credit notes, with a PDF and a PAY by square payment QR code. If you just need one invoice quickly, use our invoice generator, no sign-up needed; work out VAT with the VAT calculator. You can open an account for free and see the plans in our pricing.

Step-by-step guides: How to issue an invoice as a sole trader, Advance invoices, Credit notes and corrective invoices, Invoicing foreign clients and VAT registration in Slovakia.