Legal Q&A · Debt Recovery

What default interest can I claim on an unpaid invoice?

Law as at 21 July 2026

Answered by , Czech and Slovak attorney, admitted to the Slovak and Czech Bars (SAK 300422 · ČAK 19654).

Short answer

If the debtor fails to pay on time, you are entitled to default interest in addition to principal. In civil relationships, the statutory rate is five percentage points above the European Central Bank's base interest rate. In commercial relationships between businesses, it is the ECB rate plus eight percentage points (or a fixed nine-point uplift), together with a flat EUR 40 recovery cost payment. A rate higher than the statutory rate may be agreed in the contract.

Must default interest be agreed in the contract?

As soon as a debtor defaults on a monetary debt, the creditor is entitled to claim default interest alongside principal directly by law; no separate agreement is needed. In civil relationships, this follows from Section 517(2) of the Civil Code, which refers the rate to implementing legislation. Government Regulation No. 87/1995 Coll. sets default interest at five percentage points above the European Central Bank’s base interest rate applicable on the first day of default (Section 3).

What rate applies between businesses?

For late payment between businesses in a commercial relationship, Section 369 of the Commercial Code applies. If the parties have not agreed the interest rate, Government Regulation No. 21/2013 Coll. sets it at the ECB base rate plus eight percentage points, determined for each calendar half-year of default (Section 1(1)). The creditor may instead choose a fixed ECB rate plus nine percentage points for the entire default period (Section 1(2)). In commercial relationships, the creditor is also entitled to a one-off flat EUR 40 payment for recovery costs, regardless of the duration of default (Section 2).

Can a higher rate be agreed?

The statutory rate provides a baseline entitlement: the contract may stipulate higher default interest or a contractual penalty. Consumer contracts, however, are subject to statutory limits on penalties. When preparing commercial agreements, we therefore structure interest, payment deadlines and sanctions to be both valid and enforceable.

How to claim interest

Default interest is claimed with principal, usually first through a pre-action payment demand specifying principal, interest and the flat payment, followed by an action through debt recovery if the debtor does not pay. We can handle the entire process against a Slovak debtor, from demand through enforcement, through our debt recovery in Slovakia service.

This answer provides general information on the law as at 21 July 2026. It does not constitute legal services or replace an assessment of an individual case. The details of your situation may differ. Book a consultation to discuss them.

More legal questions

All questions and answers
  1. When does a claim for restitution of unjust enrichment become time-barred? Two years from learning that enrichment occurred and who was enriched at your expense; no later than three years from the enrichment, or ten years for intentional enrichment. Both periods run concurrently and the claim becomes time-barred when the earlier one expires. This regime does not apply to commercial relationships: a four-year period under the Commercial Code runs from the enrichment regardless of your knowledge.
  2. We have a final Swiss judgment. How do we enforce it in Slovakia? In two stages. Switzerland is outside the EU, so the 2007 Lugano Convention applies rather than Brussels Ia: a Slovak court must first declare the judgment enforceable before an enforcement application can be filed. You need the judgment, an Annex V certificate from the court of origin and, if requested by the court, a certified translation of the necessary documents. This procedure must be completed before final recovery; however, provisional and protective measures under Article 47 may protect assets at an earlier stage.
  3. The lender wants the property to become theirs automatically if the loan is not repaid. Is that legal? No. An agreement concluded before the debt falls due under which the creditor would acquire ownership of the collateral is invalid by law: this is prohibited forfeiture of collateral. Courts assess the true purpose of the entire transaction, so a sale or gift agreement signed alongside a loan 'just in case' will not stand either. The creditor should obtain payment by selling the collateral and return the surplus proceeds to the debtor; the same rule applies to a transfer of rights by way of security.
  4. How do we check a new customer before supplying on credit? Before the first credit delivery, review public registers: the Commercial Register and document collection, financial statements, Financial Administration lists of tax debtors and VAT deregistration grounds and its tax reliability index, the Central Register of Enforcement, insolvency records and the Commercial Bulletin, and social and health insurance debtor lists. It takes about fifteen minutes and guides terms such as advance payments, retention of title, shorter maturities or security.

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Mgr. Patrik Tulinský, LL.M. Czech and Slovak attorney · SAK 300422 · ČAK 19654

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