How do I know if a cell phone is compatible with Bell Canada?

[m.kester]

I want to buy a cell phone/blackberry from ebay to save money but my provider is Bell Mobility. How can I make sure that they will activate it?

[3ntropy]

if it's gsm, it should have at least tri-band frequency capability. if it does, than it will be compatible. quad band is the best. buy a gsm phone.