After registration, changes to the registration data can be made free of charge via the mutation function in the Swiss O Week registration portal. After the registration deadline on 31.05.2023 (competitive classes) or 05.07.2023 (open classes), it is no longer possible to change categories. Changes are to be made online in any case, using the link that was sent by email with the registration confirmation.

Changes of SI-Cards are always possible free of charge.