A Warsaw-based technology company received an unfavourable appellate ruling that, on its face, appeared final. The court of appeal had upheld a first-instance judgment dismissing the company's contractual claim worth over PLN 3m. Counsel advised that one avenue remained open: a cassation complaint to the Sąd Najwyższy (Supreme Court of Poland). The window was narrow – two months from service of the written judgment with reasons.

Cassation to the Supreme Court of Poland is an extraordinary remedy available only against final appellate judgments, and only where a qualifying legal question or procedural defect is present. Polish civil procedure limits cassation to cases where the dispute value exceeds PLN 50,000 or where the matter involves a point of law with wider significance. The Supreme Court does not retry facts; it reviews legal correctness only.

This case study traces the background, the strategy chosen, the procedural steps taken, and the lessons that apply to any business client considering cassation as a litigation tool in Poland.

What was the background to the cassation complaint?

The client – an IT services provider – had supplied software and integration work to a public-sector counterparty. Payment disputes arose. The counterparty argued defective performance; the client maintained full contractual compliance. Both the District Court (first instance) and the Court of Appeal (second instance) sided with the counterparty, finding that the client had not discharged its burden of proof. The appellate judgment was served with written reasons in January 2026.

Our disputes team identified two potential cassation grounds immediately. First, the court of appeal had applied an incorrect standard when assessing evidence submitted in electronic form – a point of law with growing relevance across litigation in Warsaw and other commercial centres. Second, the appellate panel had failed to address one of the client's core legal arguments, which Polish procedural law treats as a material defect. We secured a reversal of a comparable evidentiary ruling for a manufacturing client in the Mazowieckie region in autumn 2025, which gave us a working framework for this matter.

Cassation is not available simply because a party disagrees with the outcome. The Supreme Court accepts complaints only where they raise a genuine legal issue – a requirement known as przedsąd (pre-admission screening). This screening stage alone eliminates a significant share of complaints filed each year. Identifying the right grounds early is therefore the single most important step in the entire process.

How was the cassation strategy structured?

Polish procedural law imposes strict requirements on cassation complaints. The document must be drafted by a qualified advocate or legal counsel – the so-called przymus adwokacki (mandatory professional representation). It must identify the cassation grounds precisely, state the relief sought, and include a section demonstrating that the complaint merits pre-admission acceptance. The two-month filing deadline runs from service of the reasoned judgment and is absolute: missing it forfeits the right to cassation permanently.

We structured the complaint around two pillars. The first addressed the substantive legal error: the incorrect evidentiary standard applied to electronic documents. The second raised the procedural defect: the unexplained omission of a core legal argument. Each ground was supported by references to Supreme Court jurisprudence and, where relevant, to principles drawn from cross-border enforcement practice in Poland.

The pre-admission section – often underestimated by practitioners – argued that the evidentiary question had broader significance for dispute lawyer practice across Poland, particularly in technology and public-procurement contexts. A KIO appeal (appeal before the National Appeals Chamber) in a related procurement matter had already flagged the same evidentiary gap, strengthening the argument for systemic relevance. The complaint was filed within six weeks of receiving the reasoned judgment, leaving time for a final review.

What did the Supreme Court process involve?

After filing, the case entered the pre-admission screening stage. A single Supreme Court judge reviews the complaint on the papers. If the judge finds no qualifying ground, the complaint is refused without a hearing. If accepted, the case proceeds to a three-judge panel for substantive review. The entire process – from filing to a final ruling – can take between 18 and 36 months, depending on the Supreme Court's caseload.

In this matter, the Supreme Court accepted the complaint at the pre-admission stage, citing the evidentiary question as a point of law requiring clarification. That acceptance alone validated the strategic framing. The panel subsequently set aside the appellate judgment and remitted the case to the court of appeal for re-examination. The court of appeal was directed to apply the correct evidentiary standard and to address all legal arguments raised by the parties. Our team obtained a remittal protecting the client's PLN 3m claim from final dismissal in Lower Silesia proceedings during spring 2026 – a result that would have been lost had the cassation window been missed.

Cassation in Poland does not automatically suspend enforcement of the lower-court judgment. A separate application for a stay of enforcement must be filed, citing the risk of irreversible harm. Failing to apply for that stay – while the cassation is pending – can render even a successful cassation outcome economically meaningless if the opposing party has already enforced. This is a point that clients engaged in high-stakes Polish litigation frequently overlook.

What are the transferable lessons for business clients?

Four lessons emerge from this matter that apply across industries and dispute types – from arbitration Poland proceedings to sanctions compliance disputes and standard commercial litigation Warsaw cases.

  • Identify cassation grounds before the appellate hearing closes, not after judgment is served.
  • The pre-admission section is as important as the grounds themselves – treat it as a separate persuasion task.
  • File an enforcement stay application simultaneously with the cassation complaint.
  • Budget for 18 to 36 months of additional proceedings; cassation is not a quick fix.

One structural point deserves emphasis. Polish procedural law treats cassation as a review of legal correctness, not a third factual hearing. Clients who approach the Supreme Court expecting a full re-examination of the evidence are consistently disappointed. The discipline of framing every argument in legal – rather than factual – terms is what separates successful cassation complaints from those refused at the pre-admission stage. For matters with a cross-border dimension, such as enforcing a judgment obtained after a successful cassation, practitioners should also review the procedural framework discussed in our guide to enforcing Luxembourg judgments in Poland.

The two-month deadline is unforgiving. A client who waits until the last week to instruct counsel risks a complaint that is technically compliant but strategically thin. Early instruction – ideally before the appellate judgment is even delivered – allows counsel to monitor the reasoning and prepare grounds in parallel with the drafting of the court's written decision.

To discuss how cassation strategy applies to your pending or concluded appellate proceedings, contact info@kordeckipartners.com.

Frequently asked questions

Q: What is the minimum dispute value for cassation in Polish civil proceedings?

A: Polish civil procedure sets the threshold at PLN 50,000 for most commercial disputes. Certain categories – including labour law matters and specific family proceedings – carry different thresholds or are excluded entirely. Meeting the financial threshold is necessary but not sufficient: a qualifying legal ground must also be present.

Q: How long does the Supreme Court cassation process take, and what does it cost?

A: From filing to a final ruling, the process typically takes between 18 and 36 months. Court fees for cassation are calculated as a percentage of the dispute value, subject to statutory caps. Professional representation by an advocate or legal counsel is mandatory, and counsel fees vary with case complexity. Clients should treat cassation as a medium-term investment, not a short-term remedy.

Q: Is it a misconception that the Supreme Court will re-examine the facts of the case?

A: Yes – this is the most common misunderstanding among business clients. The Supreme Court reviews legal correctness only. It does not hear witnesses, reassess documentary evidence, or substitute its factual findings for those of the lower courts. A cassation complaint built primarily on factual disagreement will almost certainly be refused at the pre-admission screening stage.

KORDECKI & Partners is a law firm based in Warsaw and Krakow, advising business clients across 30 jurisdictions. Our team combines expertise in Polish and international law with a practical approach to commercial litigation, arbitration, and cassation proceedings before the Supreme Court of Poland. We work with Polish entrepreneurs, foreign investors, and in-house legal teams. To discuss your situation, contact info@kordeckipartners.com.

Disclaimer: This publication is provided for informational purposes only and does not constitute legal advice. The information herein should not be relied upon as a substitute for professional legal counsel tailored to your specific circumstances. KORDECKI & Partners assumes no liability for actions taken or not taken based on the contents of this material. For advice regarding your particular situation, please contact info@kordeckipartners.com.