Every so often, an airline publishes a fare that's wildly wrong. A business-class seat to Asia for the price of economy. A transatlantic return for less than a train ticket. For a few hours, anyone who spots it can book it. Then the question becomes: will the airline actually let you fly?
In Canada, the honest answer is "maybe, and it depends on how obvious the mistake was." Here's how these fares happen, how to catch one, and what the rules say when the airline tries to cancel.
What is a mistake fare?
A mistake fare (or error fare) is a ticket sold at a price the airline never meant to offer. It's different from a sale. A sale is a low price on purpose. A mistake is a price nobody at the airline approved, and it usually disappears within hours once someone notices.
How do they happen?
- Currency slips. A fare meant in one currency gets published in another, or the conversion goes wrong. In 2015, United sold first-class tickets from the U.K. to the U.S. for a tiny fraction of the real price after a currency error on its Danish site.
- Missing pieces. Airline fares are built from parts: a base fare, fuel surcharges, taxes. If a surcharge drops out of the calculation, the total can fall by hundreds of dollars.
- Plain typos. People file fares by hand. A missing zero turns $1,500 into $150.
- Glitches between systems. Fares pass through several companies' systems before they reach you, and a bug anywhere along the chain can produce a nonsensical price.
Can an airline cancel one in Canada?
No, not automatically. There's no law in Canada that would force an airline to honour a price that was published by mistake.
The key case is a 2014 decision by the Canadian Transportation Agency (Decision No. 202-C-A-2014). Swiss International Air Lines sold first- and business-class tickets from Yangon, Myanmar, to Montreal, Toronto and Ottawa for a total of about US$1,000, taxes included. The real fares were US$10,000 to US$15,000. Swiss cancelled the tickets and refunded 83 passengers, who complained that a deal is a deal.
The Agency ruled for the airline. Its reasoning: a reasonable person ought to have known that a first-class ticket from Asia to Canada for about US$1,000 wasn't just a low price but a mistake. When the price is a fundamental part of the contract and the buyer should have known it was wrong, there's no real agreement, so the airline can cancel and refund.
The takeaway: the more absurd the fare, the less protection you have. A fare that's 40% below normal might just look like a great sale. A first-class fare 90% below normal will be very hard to hold an airline to.
What about U.S. flights?
The U.S. has a rule that stops airlines from raising the price of a ticket after you've paid for it. But in 2015 the U.S. Department of Transportation said it would not enforce that rule against genuine mistake fares, provided the airline refunds the ticket and reimburses the traveller's reasonable, provable out-of-pocket costs, like non-refundable hotel bookings or tours booked for the trip.
So on U.S. routes, even if the airline cancels, you shouldn't end up out of pocket for what you spent in good faith. Keep every receipt.
How to catch one
- Be ready to book fast. Mistake fares often last just a few hours. Know your travel dates, keep your passport details handy, and don't wait until tomorrow to decide.
- Follow deal alerts. Nobody finds these by casually searching. Deal websites and newsletters spot and share them quickly.
- Book directly with the airline when you can. If the fare survives, you'll be dealing with one company instead of two if anything changes.
Protecting yourself after you book
- Don't call the airline to ask whether it's a mistake. You're only drawing attention to the booking. Wait for them to contact you.
- Hold off on non-refundable plans. Wait a week or two before booking hotels, tours or connecting flights you can't cancel. Most cancellations tend to happen in the first few days after booking.
- Pay with a credit card. If a refund stalls, a credit card lets you dispute the charge.
- Keep screenshots. Save the price, the fare rules and the confirmation email. If there's ever a dispute later, you'll want proof showing exactly what you bought.
Is it ethical to book a mistake fare?
It's a fair question. Booking a price the airline published isn't a trick; you're buying what was offered. But when a fare is so low that you know it's a mistake, that's exactly the situation where Canadian regulators have said the airline can cancel. Go in expecting it might be taken back, and count it as a bonus if you get to fly.
Not legal advice. This is a plain-language summary of published decisions and policies as of September 2026. Rules change and every case is different; if there's a lot of money at stake, check the airline's tariff and speak to a lawyer or the Canadian Transportation Agency.
Most great fares are not mistakes; they're ordinary seats priced well below normal. OddFare continuously looks for them on flights out of Toronto. See today's deals.