In Canada all the "players" have agreements in place to use any tower. For example, if I am in Ontario, my Sasktel phone will happily connect to a Bell tower. When I am in Saskatchewan, my Bell phone connects to Sasktel towers.
USA is quite different as there are few such agreements in place. However if you have an international package on the phone--then in Canada you would have that same feature (tested on Metro PCS and T-Mobile).
When I'm traveling south of the border, both my Bell and Sasktel phones will use various towers--but since I only have a roaming contract on the Bell phone I would only use the Sasktel if I were in an emergency situation, where the Bell phone refused to connect.
I think one reason there are these differences is that cell towers are not independently owned in Canada. They belong to the various networks.
I did have a Verzion device and found that on the trip south to Florida there were places where I had no service.
But in North Dakota a T-Motile won't connect to a Verizon tower.
Currently Verizon still has the best coverage.
Costs for cell phone service in Canada are pretty much always higher than those in USA.
Regards, Don
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