In judgment No. 21 Cdo 94/2026, the Supreme Court of the Czech Republic (Nejvyšší soud) rejected the practice of treating a gas bill based on data from the distribution system operator as correct unless the customer proves otherwise. Where no such presumption arises from statute or contract, the supplier bears the burden of proving the quantity actually consumed. The decision has practical consequences not only for energy disputes but for any contract under which invoicing is based on metering, meter readings or estimates.
What was the dispute about?
A natural gas supplier sued a business customer for payment of more than CZK 819,000 for gas supplies. The customer disputed the bill. According to available information, the disputed amount related largely to a period for which no direct meter reading was available and consumption was estimated; the customer denied having consumed that quantity of gas.
The lower courts largely upheld the claim. They proceeded on the basis that a bill based on the distribution system operator’s data must be regarded as correct and that the customer had not properly lodged a complaint. In effect, they shifted the burden of proof to the customer, who was expected to prove that it had not consumed gas in the amount billed.
What did the Supreme Court say?
The Supreme Court set aside the judgment of the appellate court (the Regional Court in Brno – Krajský soud v Brně) and remitted the case for further proceedings. Based on the published information, its conclusions can be summarised in four points:
- The general allocation of the burden of proof applies. In adversarial proceedings, each party bears the burden of allegation and the burden of proof regarding the facts from which it derives favourable legal consequences. A supplier seeking payment must therefore allege and prove how much gas the customer actually consumed.
- The law establishes no presumption that a bill is correct. Neither the Czech Energy Act nor its implementing regulations create a presumption that a gas consumption bill is correct.
- Nor did the contract contain such a presumption. The general terms and conditions did regulate complaints, but they did not attach to a failure to complain the consequence that the bill is deemed correct.
- A court cannot “read in” a presumption. As the Supreme Court stated in its press release:
“A legal presumption cannot be created by a court decision without support in statute or contract.” (Translation; original: „Právní domněnku nelze vytvářet soudním rozhodnutím bez opory v zákoně nebo smlouvě.“)
The mere existence of a bill is therefore not enough to shift the burden of proof automatically to the customer. The appellate court must reassess the claim – this time without a presumption that the bill is correct.
Contractual presumptions and fictions: from prohibition to (limited) admissibility
The decision is part of a longer development in case law on whether parties may themselves agree on a legal presumption or fiction in a contract – typically wording such as “it is presumed that…” or “shall be deemed…”.
- Under the former legislation, the Supreme Court held that a legal presumption can be established only by statute, not by agreement of the parties (e.g. judgment No. 32 Cdo 2536/2007 of 3 December 2008). In judgment No. 32 Cdo 1287/2018 of 4 March 2020, it added that a contractual presumption or fiction alters the allocation of the burden of proof, which procedural law does not allow the parties to do.
- The turning point came with judgment No. 23 Cdo 1001/2021 of 23 March 2022. Referring to party autonomy under the 2012 Czech Civil Code, the Supreme Court accepted that clauses in the form of a presumption or fiction cannot be regarded as invalid in general and must be assessed individually. The case concerned a clause in a contract for work under which the work “is deemed duly and timely handed over” if the customer repeatedly fails to attend the handover.
- Judgment No. 21 Cdo 94/2026 builds on this development. According to legal commentary, the Supreme Court expressly accepted that the situation envisaged by Section 133 of the Czech Code of Civil Procedure (občanský soudní řád) – where the court regards a fact as proven unless the contrary emerges – may arise not only by statute but, albeit only in exceptional cases, also from a contractual agreement between the parties. This is not, however, a general departure from the prohibition of so-called evidence agreements: a contractual presumption must first stand up as a valid agreement under substantive law.
When assessing such a clause, the decisive factors will include its actual content and the parties’ intention, its compatibility with mandatory statutory provisions and good morals, and the relative position of the parties – a clause agreed between two businesses of equal standing will be assessed differently from one imposed by the stronger party on the weaker one.
What does this mean for customers?
- If you disagree with a bill, you do not automatically have to prove that you did not consume. Unless statute or contract establishes a presumption of correctness, it is for the supplier to prove actual consumption in a dispute.
- Still, complain in time and in writing. The decision does not mean that complaint deadlines are irrelevant. The contract or general terms may attach specific consequences to a failure to complain – and such a clause may be valid.
- Read the general terms and conditions. Wording such as “the bill shall be deemed accepted unless a complaint is lodged by…” can have significant procedural effects.
- Document your meter readings. Photographs and your own readings on the relevant dates are valuable evidence in a dispute – especially for periods in which the supplier billed an estimate.
What does this mean for suppliers and other businesses that invoice based on metering?
The conclusions of the decision are not limited to the energy sector. They concern anyone who invoices on the basis of meter readings, measurements, statements or estimates – for example in services, leases with service-charge settlements, telecommunications or logistics.
- Review your contracts and general terms. If you want an unchallenged bill to be deemed correct, the contract must say so expressly and clearly. Merely regulating the complaints procedure is not enough.
- Draft clauses with their validity in mind. A contractual presumption must not conflict with mandatory statutory provisions or good morals; in relation to consumers and weaker contracting parties, there is a risk that a court will not uphold the clause.
- Keep your metering records. In a dispute you will have to prove actual consumption – distributor data, meter-reading records, the estimation method and any subsequent reconciliation.
- Expect courts to take a stricter approach. The decision corrects the previous practice of the lower courts; claims based solely on an issued invoice may fail.
Conclusion
Judgment No. 21 Cdo 94/2026 is a reminder of a basic rule of civil procedure: whoever asserts something must prove it. An exception may be established by statute – and, to a limited extent, by a well-drafted and valid contract. For businesses on both sides of a contract, this is a reason to review provisions on billing, complaints and meter readings before they become the subject of a dispute.
Would you like your contracts or general terms reviewed under Czech law, or are you dealing with a billing dispute? Contact us at praha@machlegal.eu or +420 245 008 552.
This article is current as of 12 October 2026 and is based on the press release of the Supreme Court of the Czech Republic and on legal commentary on the decision. It does not constitute legal advice in any specific matter.