The agency was responding to a complaint alleging that WestJet's international tariff — a contract between a customer and the carrier — has several "unreasonable and conflicting" rules for customers unable to travel because a flight has been oversold.
The Calgary-based airline has been given until July 15 to revise its rules.
It's WestJet's policy not to oversell flights intentionally, but the CTA ruling said the airline must remove a provision that exempts it from liability in the event customers are bumped anyway — whether or not it happens for reasons outside WestJet's control or if the airline gives a passenger a travel credit or full refund.
Wednesday's ruling is separate from a CTA ruling last month that passengers on WestJet rival Air Canada (TSX:AC.B) were entitled to higher compensation if they're bumped from overbooked domestic flights.
It said Air Canada's existing practice of paying $100 in cash or a $200 travel voucher is unreasonable and it gave the airline 30 days to submit new compensation guidelines.
The agency sided with Gabor Lukacs, a former University of Manitoba math professor, who has challenged several airline industry practices. Lukacs also complained about WestJet's bumping practices.
Also Wednesday, Transportation Canada issued an air operator certificate for WestJet's new regional service, Encore, which launches in Western Canada on June 24.
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