Stopping at an airport different from destination

I have a Canadian Visa and an air ticket to Toronto via Montreal. However, I would like to stop at Montréal instead of going to Toronto. While I asked my travel agent to cancel this booking, he refused to do so saying it would cost me more. Instead, he asked me to check in only upto Montreal.
Is this possible?
Update: Finally, it turned out to be not as scary as made out in the present answer: When I checked in at Chennai, I asked them to check my luggages only upto Montréal. And, I cleared customs at Montréal and collected my luggage and just walked out...
Best Answer
Assuming you have no further flights on the same ticket (like the return) you can get off anywhere you want. The airline will cancel all future flights on that ticket.
Your checked suitcase will probably end up on a Toronto baggage carousel, going round and round and eventually feeling quite rejected. It will eventually get picked up by airport security for loitering and then spend several days being passed from one handling service to another, with some unpleasant security searches in between. This could lead to long-term trust issues and require a lot of suitcase therapy.
( If you clear customs in Montreal you will have your bags and can just walk out. )
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What is it called when you stop at a different airport?
A layover is a broad term that means any connection between flights. This could include a stop as short as 30 minutes (depending upon the airport) or as long as four hours (or up to 23 hours and 59 minutes on international flights).Can I get off at my layover instead of destination?
You can get off at the layover stop, but checked luggage will keep on flying to the final destination.Does stopping in airport count as visiting a country?
\u201cA visit only counts if you leave the airport\u2026or sleep in the airport overnight\u201d \u201cIt counts if you eat there, preferably something local\u201d \u201cIt counts if you go outside and step on the ground\u201dWhen you make a stop in an airport?
Layovers or Stopovers For domestic flights, it's called a layover if it's less than four hours, or a stopover if it's longer. In general, you can use the two words interchangeably, or even use the word "connection" for a short-term stop, and everyone will know what you mean.Ep 5: Safety from the airport to destination
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