In Canada What Main lte bands are in use?

Lets look at what Canada's # 2 and # 3 Carriers (Telus / Koodo) have in Active LTE band frequencies:

Telus / Bell are "Bellus" as you may have heard others quote, they share the network coast to cost, unlike Rogers who own's its entire network by itself, Telus and Bell decided to share and double up on the resources in their territory.

Between Bell & Telus:

British Columbia; Telus
Alberta; Telus
Saskatchewan; Bell & Telus Minority, as SaskTel is a dominant Regional Carrier.
Manitoba; Bell and Telus
Ontario; Bell and minor by Telus
Quebec; Bell & Telus and Videtron is gaining as a dominant Regional Carrier. 
New Brunswick, Nova Scotia, New Found Land, PEI: Bell and many smaller regional carriers like EastLink. 

Does it matter to you who owns what part of the network? Absolutely not, because you are not roaming. The way Bellus (Bell+Telus you get it now right?) has setup the network, either one of their customer's are able to seamlessly transition from one carrier to another without interruption in any call/text/data services. All customers get access to all available LTE Bands, 3G and VoLTE Services. 

So what LTE bands do you need to get maximum quality of service? 

Main one is Band 4. However Telus / Bell deploy Band 2/4/5/7/12/13/17/29. 

​Please note: Koodo and Virgin Mobile have access to every single above mentioned LTE band as well, there are no restrictions in place despite being "Sub-Carrier's") much like Fido does with Rogers. 

For superior indoor coverage, you will need Bands 5/12/13/17 (Band 29 as well but thats not available on all phones sold before 2016). 

For more capacity / further LTE-A speeds, Band 2 and 7. 

Now you cannot access ALL available LTE bands at once, however having a phone such as iPhone 6S and newer, allows you to get service everywhere that its available and access to wider range of LTE bands as well as Carrier Aggregation = Combining certain LTE frequency bands to increase bandwidth leading to higher theoretical speeds in essence.