Foreign travelers who fly to or transit through Canada will need an Electronic Travel Authorization (eTA). Exceptions include American citizens and visitors with a valid visa.
The eTA is not required on a per trip basis. Once approved, the eTA is valid for five years or until the passport expires, whichever comes first. For this reason, application fees are not reimbursable as the eTA is not specific to U of T travel, but is rather considered a general travel document, similar to a passport.