Yes. A sale contract needs no written form: it arose through ordering and delivery, even orally or by conduct. In court, the issue is proving delivery and the agreed price; accepted invoices, delivery notes, emails and established dealings usually suffice. Watch limitation periods and remember that a due date added unilaterally to an invoice is not an agreed due date.
For years, business worked by phone and email: order, delivery, invoice, payment. Then a customer stopped paying, and the file contains nothing resembling a contract. The good news is that such disputes depend on evidence of what was actually supplied and agreed in return.
A contract arose even without paper
The Commercial Code (Act No. 513/1991 Coll.) does not require written form for sale contracts or most ordinary supplies. Agreement on the essential terms, what will be supplied and at what price, is sufficient (Section 269(1)). Acceptance need not even be spoken:
Having regard to the offer’s content, practices established between the parties or usages applicable under this Act, the addressee may express acceptance by performing an act, such as dispatching goods or paying the purchase price, without notifying the offeror.
— Section 275(4) of the Commercial Code (unofficial English translation)
We discuss when writing is mandatory in must a contract be written to be valid?. Here, the question is how to prove an oral agreement’s content during recovery.
How to prove delivery and price
The court needs to establish delivery, quantity and price. Existing records provide the evidence: invoices and payments, delivery notes, orders, emails and transport documents. The history of dealings also matters: interpretation takes account of established practices and subsequent conduct (Section 266(3)).
In case No. 2 Obo 61/2008, the Slovak Supreme Court stated that a supplier’s invoice becomes evidence of delivery only when the customer accepts all its particulars. Invoices paid without reservation therefore support the established price and scope of dealings; unpaid invoices need other supporting delivery documents. A debtor’s argument that the invoices are absent from its accounts does not succeed: in Supreme Court case No. 5 Obdo 62/2018, the conclusion stood that the defendant’s failure to record documents cannot prejudice the creditor.
Where oral agreements fail
Case No. 2 Obo 61/2008 also warns that an invoice reflects rather than replaces the agreement. A due date you add unilaterally is not an agreed due date. In that dispute, the court counted time from delivery, so a claim pursued using invoice dates was already time-barred. Commercial supplies have a four-year limitation period; see when a claim becomes time-barred for calculation and suspension.
A second warning concerns future evidence. While the relationship works, obtain at least email confirmation or a signed delivery note. This inexpensive evidence can later compensate for the missing written contract.
How we can help
Our debt recovery service assesses which documents provide sound evidence and plans the approach. We first send a pre-action demand. If unsuccessful, we prepare a payment order application based on invoices, delivery notes and correspondence. Contact us before the oldest supplies become time-barred.
This answer provides general information on the law as at 29 August 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.
