The CJEU’s C-609/19 judgment and Swiss franc loans.

On 10 June 2021, the Court of Justice of the European Union (CJEU) delivered its judgment in BNP Paribas Personal Finance (case C-609/19). It sets out what a bank must explain to a consumer who borrows in a foreign currency. The French Cour de cassation has applied this transparency standard since 2022. It did so again in its two published rulings of 9 July 2025, recent case law, liable to change.

The original dispute.

The borrower had taken out a mortgage with BNP Paribas Personal Finance, denominated in Swiss francs and repayable in euros. Each instalment was calculated in Swiss francs, then converted into euros at the day’s rate.

On 15 January 2015, the Swiss National Bank abandoned the franc’s floor against the euro, and the franc rose. Despite years of repayments, the outstanding capital, converted into euros, exceeded the amount borrowed. The borrower brought proceedings before the Lagny‑sur‑Marne district court, which referred questions to the CJEU.

The questions referred.

Directive 93/13/EEC of 5 April 1993 protects consumers against unfair terms. An unfair term creates, to the consumer’s detriment, a significant imbalance between the parties’ rights and obligations. The court asked the CJEU how this text applies to exchange‑rate clauses.

• Do the clauses that place the exchange‑rate risk on the borrower define the main subject matter of the contract, within the meaning of article 4(2) of the directive?
• What transparency does the directive require for these clauses?
• Is the significant imbalance assessed only on the day of signing, or in light of later movements in the exchange rate?

The main subject matter of the contract.

The directive excludes from the unfairness review the terms that define the main subject matter of the contract, on one condition. Those terms must be drafted in plain and intelligible language.

The Court reads this exception strictly. A term falls within the main subject matter if it sets an essential performance under the contract. The exchange‑rate clauses at issue can qualify, because they set the currency of the loan and how the instalments are converted.

That qualification protects the term only if it is clear. If it is not, the judge can review whether it is unfair.

The transparency requirement.

For the Court, transparency is not limited to grammatically correct drafting. The consumer must be able to assess, from precise information, the economic consequences of the term for their obligations. The benchmark is the average consumer, “reasonably well informed and reasonably observant and circumspect”.

For a foreign currency loan, the information expected from the bank covers several points in practice.

• How the exchange mechanism works, from the instalment calculated in Swiss francs to its conversion into euros and the outstanding capital.
• Figured simulations of adverse scenarios, including a sharp and lasting rise of the Swiss franc.
• A clear warning that the borrower alone bears the exchange‑rate risk.
• Any protective mechanisms, such as a conversion option or a cap, and their limits.

General documentation may not be enough. The bank must show that it enabled the consumer to understand the economic consequences of the transaction.

The significant imbalance.

The Court confirms that the significant imbalance is assessed at the date of signing. The judge takes into account the circumstances the bank could know at that date and their possible effect on the performance of the contract.

For a foreign currency loan, the judge therefore asks whether the bank could foresee, when signing, that a sharp rise in the currency would increase the borrower’s burden.

The asymmetry between the parties also matters. The borrower bears the entire exchange‑rate risk. The bank knows the currency market and has hedging instruments. This asymmetry, combined with a lack of transparency, can establish the significant imbalance.

The Cour de cassation rulings that apply it.

The ruling of 30 March 2022.

On 30 March 2022, in a published ruling (no. 19-17.996), the First Civil Chamber settled the question of limitation, meaning the time limit for bringing a claim. A claim to have an unfair term deemed unwritten is not subject to the five‑year limitation period. The borrower can therefore challenge the term long after signing. The Court also requires the bank to explain the exchange mechanism in concrete terms.

The ruling of 12 July 2023.

In a published ruling of 12 July 2023 (no. 22-17.030), the same chamber set the starting point of the claim for restitution of the sums paid. The five‑year period runs from the court decision that finds the term unfair.

The rulings of 9 July 2025.

On 9 July 2025, the First Civil Chamber delivered two published rulings (no. 24-19.647 and no. 24-18.018) concerning borrowers paid in Swiss francs. This case law is recent and liable to change. The exchange‑rate risk is assessed over the whole term of the contract, taking into account foreseeable changes in the borrower’s situation. The Court thereby departed from a ruling of 1 March 2023 (no. 21-20.260). That ruling had ruled out the risk for a borrower paid in Swiss francs at signing.

In case no. 24-18.018, however, the Court dismissed the borrower’s appeal, because the bank had given clear information on the effects of a change in the exchange rate.

The documents that matter.

Transparency is proved with documents. The judge looks in particular at the following.

• The pre‑contractual information sheet given to the borrower, dated and signed.
• The simulations of adverse exchange‑rate scenarios, tailored to the amount, the term and the borrower’s situation.
• The contract documents that explain the exchange mechanism.
• Records of exchanges with the adviser, such as meeting notes, emails or branch notes.
• Where relevant, the documents on protective mechanisms and their limits.

When these documents are missing or stay general, the bank finds it harder to show that it informed the borrower. The judge assesses each case.

The average consumer.

The average consumer test is objective. The judge asks whether a reasonably well‑informed consumer would have understood the risk from the documents received.

According to the CJEU (21 September 2023, C-139/22), the borrower’s particular knowledge does not change this test. The bank must inform the borrower even when they are its own employee and know the field.

The banks’ arguments.

Banks raise several arguments in their defence.

• The main subject matter. The term would escape review because it defines the loan. The judge then checks whether it is plain and intelligible, and reviews its fairness if it is not.
• Limitation. The ruling of 30 March 2022 rules out the five‑year limitation period for a claim to have the term deemed unwritten.
• No imbalance. The exchange rate could move either way. The judge then looks at the asymmetry between the bank and the borrower, and at the protection the borrower had.

Each case remains a matter for the judge.

What the judgment leaves open.

Judgment C-609/19 leaves several questions open. On the same day, the CJEU dealt with the limitation of restitution claims in cases C-776/19 to C-782/19. The Cour de cassation dealt with the position of borrowers paid in Swiss francs in its rulings of 9 July 2025, recent case law, liable to change.

What it means for a borrower.

If the bank cannot show that it gave sufficient information, the exchange‑rate term can be deemed unwritten. Depending on the decision, the loan is then recalculated as if it had been made in euros. Restitution is calculated on the gap between the sums paid and those that would have been due. The judge assesses each situation.

In the Swiss franc loan programme, reviewing your case costs you nothing. Hello Justice covers the flat fees of COGEP AVOCATS (€5,000). Costs and disbursements remain capped at €300 including VAT. If the case succeeds, a success fee of 14% including VAT, shared between the lawyer and Hello Justice, is taken from the sums actually recovered. If it fails, you owe Hello Justice nothing.

The programme’s eligibility test shows whether your loan falls within the period concerned. A specialised partner lawyer then analyses its eligibility. We follow all the decisions in our review of the 2022-2025 rulings.