Before you use my guide, I would recommend checking out this tool:
It is the best site I have found for quickly answering this question. However, I am not sure how they keep their database updated. My guide may still be helpful for brand new devices or if you cannot find your device on their list.
If that site doesn’t work for you or you are looking to better understand mobile carrier compatibility, here is my guide:
Step 1: Which phone do you have?
This might seem like a silly question, but many people do not know anything about the phone they are holding in their hand. I have heard enough people say “an android” or “iPhone 5G” to know that this is a real issue for some. Looking on the back of your phone can be helpful as identifiers can be found. On an iPhone, the model number starting with A (like A1549 for iPhone 6) is useful for identifying.
The best site to assist with identifying a phone is gsmarena.com. To find your phone, do a search on their site (top right corner) with what you know about your phone (like the model name and manufacturer).
If their search doesn’t help, try using a site search with google, like this:
site:gsmarena.com <brand> <model> <any other information>
site:gsmarena.com htc one m8
Now check out the full phone specifications from the results. Does the picture look like your phone? If so, you probably have the right device. If not, try to refine your search. Going to the site of the mobile carrier you purchased your phone from may help you identify it.
Once you have found your phone on gsmarena.com, find “Network” (top of the specifications). You may need to “expand” in the title bar to see all the compatible network frequencies. The important part to take note of is the 2G, 3G, and 4G network protocols (like GSM, CDMA, HSPDA, LTE, etc) and frequencies. This is what we will need to determine if your phone will work on a carrier.
Remember that where you bought your phone can have an impact on which frequencies it supports. European and North American versions of a phone may look exactly the same and support the same protocols, but use different and incompatible frequencies.
Step 2: Which carriers support my phone?
Here is a chart with a general overview of the major carriers and what they support. Compare the protocol and frequencies. I included 2G, but this can mostly be ignored at this point as even the most remote areas in cell coverage in Canada now tend to have at least 3G coverage. I did not include bands for LTE broadband (data) only.
You may see that your phone supports some bands and not others. While this will allow your phone to work, it will often severely hurt coverage for your device. For example, carriers that only support the LTE bands of your phone will often have issues in more rural areas that still rely heavily on 3G to provide coverage.
Ideally, you want your phone to support all the 3G and LTE bands/frequencies that your carrier provides for best coverage.
Step 3: Is your phone unlocked?
Even if your phone is compatible with a network, that still does not mean it will work. Most North American carriers will “sim lock” their phones. This means that the phone should only be able to use sim cards from the carrier you purchased it from. Carrier subsidiaries will usually be compatible even with a sim lock (like a Telus phone working on Koodo or a Fido phone working on Rogers). The carrier you bought your phone from can unlock it for you, but they can charge up to $50 for this privilege. Often you can find unlock codes online for much cheaper, but sites that provide these services can be sketchy.
Sometimes unlocking can be done purchase-free with a bit of hacking. The quickest way I have found to determine if a phone can be unlocked without buying a code is actually to search Youtube. Just search <your phone name> with the words “how to unlock”. If the person in the video points you to a site to buy an unlock code, it probably does not have a method to unlock without a code. Otherwise, if it describes a process to root or jailbreak your device, then a free way to unlock it may be possible. I would not recommend doing this yourself unless you have some technical know-how and are willing to take the chance of ruining your device.
Example of how to use this guide
As an example, I’m going to use a scenario that I ran into. It should give you a good idea of how confusing determining compatibility can be.
My friend came from Russia with her HTC Desire that she purchased in Russia. She already knew the phone was unlocked. Let’s try to figure out if it will work for any of the Canadian carriers.
First, let’s search GSM Arena for the phone: http://www.gsmarena.com/htc_desire-3077.php
Note the 2G networks. It uses GSM 850/900/1800/1900. Since Rogers uses 850/1900, then this phone is compatible with Rogers 2G network for 2G.
But what about 3G? Since this phone was purchased Russia, it uses HSDPA 900/2100 frequencies more common there. Since none of the Canadian carriers support the 900 or 2100 frequencies on 3G, this phone will not work on any of the 3G networks in Canada.
Therefore, the only option for her to use this phone in Canada is on Rogers. She would also be limited to 2G only.
Another way: Determine compatibility using IMEI number
Bell and Telus also have a way to figure out compatibility using your phone’s unique IMEI number.
Bell IMEI Checker: https://www.bell.ca/shopping/jsp/pageblock_styles/ToolBox/imeitool/imeitool.jsp
Telus Compatibility Checker: http://mobility.telus.com/en/NS/bring-own-device/check-device.shtml?INTCMP=TcomBtnBYOD)
This guide isn’t meant to help with figuring out your coverage, but compatibility. However, here are the coverage maps for the major carriers:
Links that helped me create this guide: