Swiss Arbitration Quick Tips

Swiss Arbitration Quick Tip #3: When Does the 30-Day Challenge Clock Start and End?

By Aliénor de Dardel, Homburger

An award rendered by a tribunal seated in Switzerland can be challenged before the Swiss Federal Supreme Court within 30 days of its notification (Article 190(4) Swiss Private International Law Act, PILA). But what starts the clock, how is the deadline calculated, and what if notification is defective?

First, check the notification rules. How the award must be notified is determined primarily by the parties’ agreement or the chosen arbitration rules and, if these do not address the issue, by the tribunal (Article 182(1) and (2) PILA).

Second, check what was sent and how. If the applicable rules require the signed version of the award to be delivered by post or courier, an earlier email, fax or courtesy copy will not start the challenge period. Conversely, if electronic notification has been agreed, receipt of the formally notified electronic award will start the clock.

The content matters too. If only the operative part is initially communicated and the reasons are to follow, the clock starts upon notification of the reasoned award. If the parties waived their right to reasons, notification of the operative part itself starts the clock.

Third, do not ignore an apparently defective notification. A party with actual knowledge of the award must immediately raise any alleged notification defect with the tribunal or institution. Otherwise, it may lose the right to rely on that defect in a later challenge (Article 182(4) PILA; Swiss Federal Supreme Court decision 4A_412/2025 of December 9, 2025, consid. 3.3).

Once triggered, the 30-day period cannot be extended. The day of notification is not counted, Swiss court recesses apply and, if the final day falls on a weekend or public holiday, the deadline moves to the next working day (Articles 44-46 of the Federal Supreme Court Act, only in French, German, Italian).

Finally, a request to correct, interpret or supplement the award does not suspend the challenge period. If the award is amended, a new period begins only in respect of the amended part (Article 189a(2) PILA).