A bill rises each year, and the customer pays without promptly challenging the term allowing the increase. Does an unfair clause become valid after three years? Can the supplier replace it unilaterally with new wording? On 24 September 2026, the Court of Justice of the European Union addressed these questions in SVB, Case C‑900/24, ECLI:EU:C:2026:784.

The judgment matters when examining price changes in long-term consumer contracts, especially energy supply. It does not establish that every increase is unlawful or that every customer automatically receives a refund. It explains why consumer inaction and a supplier’s unilateral amendment cannot simply rescue an already unfair price-adjustment term.

The dispute behind the judgment

The case concerns a German district-heating contract concluded in 2012 between SVB and Glarner Straße 5. A price-adjustment clause led to annual changes in the consumption charge between 2015 and 2020. In 2019, the supplier unilaterally amended the clause by relying on German district-heating legislation. The customer challenged the adjustments and sought reimbursement.

The Berlin court found the term unfair and void. It then needed answers concerning the national three-year practice and the supplier’s power to replace the clause. The judgment of 24 September 2026 addresses both questions through Articles 6(1) and 7(1) of Directive 93/13. It interprets EU law; the national court remains responsible for deciding the underlying dispute and applying that interpretation to the facts.

Three years do not cure an unfair term

The German practice under examination prevented a customer from relying on the invalidity of price increases unless they had challenged them within three years of the relevant annual statement. This could preserve the effects of the unfair term for earlier periods. The Court found that maintaining the contract in that manner did not comply with the protection required by the directive.

The important distinction is between curing unfairness and limitation of a particular claim. SVB does not abolish every national deadline or declare that all reimbursement claims last forever. Applicable periods and their starting points need separate examination under national law and the constraints imposed by EU law. A customer should therefore not delay challenging charges on the assumption that this judgment creates unlimited time.

The supplier cannot unilaterally repair the invalidity

The second part concerns a national rule or practice enabling or requiring an energy supplier to change a price-adjustment term which has been declared void for unfairness. The Court did not accept that such a unilateral power provided a compatible solution. Replacing the wording cannot simply be used to preserve the effects of a term that does not bind the consumer.

Directive 93/13 on unfair terms requires the unfair term to be disapplied and, in principle, the contract to continue if it can exist without it. Replacement by a supplementary national provision may be considered in limited circumstances to avoid cancellation of the whole contract harming the consumer. This is not a general licence for judicial rewriting or unrestricted supplier intervention. The consumer’s protection and choices remain central.

Why consumer status needs its own assessment

Glarner was a civil-law company, a detail that can easily be misunderstood. The judgment does not make every company a consumer. The directive defines a consumer as a natural person acting outside their trade or profession. In this German dispute, national law allowed the protection to be applied to Glarner.

The customer’s legal form, the purpose of the agreement and the relevant domestic rules must consequently be examined separately. A household customer and a business purchasing energy for production are not automatically in the same position. The Court’s official SVB press release identifies the particular basis for Glarner’s consumer treatment. A Greek business contract needs its own assessment; the existence of a company in the original case is not enough to transfer the result.

Not every price increase is unfair

Assessment concerns the particular contractual term, its inclusion in the agreement and its effects. A larger bill does not, by itself, establish unfairness. Relevant matters may include clarity of the mechanism, the reasons and method for changing prices, information before the contract was made and rights available to the customer.

The earlier RWE Vertrieb judgment, Case C‑92/11, helps explain transparency in price-adjustment clauses. The consumer must be able to understand the mechanism and assess its economic consequences within the framework examined. Having received a notice at some point does not automatically resolve all those questions. Equally, higher costs for a supplier do not by themselves validate every clause or justify every particular charge.

Documents that make scrutiny meaningful

A useful first assessment needs the original contract, the general terms applicable when it was signed, later versions of the clause, bills and notices of increases. The file should show when the term changed, the period covered by each charge and whether an objection was made. A simple chronology can distinguish the date of a bill from the date the contractual adjustment mechanism was altered.

Imagine two neighbouring households facing the same increase in their total bills. One might have agreed a fixed price, while the other has a different, clearly specified adjustment mechanism. The economic frustration is similar, but the legal analysis is not necessarily the same. A written request identifying the contractual basis and calculation is more useful than simply stating that the bill has become more expensive.

Practical implications for customers in Greece

SVB reinforces the need to examine the actual clause and the consequences of its invalidity. It does not decide every Greek tariff dispute or calculate a refund. The national court considers the contract, the customer’s status, the claims, evidence and deadlines, applying the EU interpretation where an equivalent issue arises.

A customer can request a documented explanation, preserve earlier terms and promptly assess the appropriate complaint or court procedure. Unilaterally stopping payment or terminating an agreement can create separate risks and requires individual evaluation. The central point is that an unfair term cannot readily acquire validity merely through the customer’s silence or a new unilateral formulation by the supplier.

Official sources and information date

The analysis draws on SVB of 24 September 2026, particularly paragraphs 34–63 and the operative part, Directive 93/13 and RWE Vertrieb. The press release provides additional context and does not replace the judgment itself. References and currency were checked on 10 October 2026.

This article was prepared with artificial-intelligence assistance and reference to the cited official sources. It provides general legal information, not individual advice or a promise of reimbursement in a particular case.