Do you have to provide two pieces of photo ID at the Telus store if you put your SIN number on the online web? I just turned 18 and ordered a phone, and I got told that.
Avoid using your SIN anywhere, especially online, if you can help it. Photo ID + credit card usually safest bet.
Usually you produce one piece of photo ID, and one other. The photo is to show you are who you say you are, and the second is linked to your credit credibility. The second might be a credit card, or SIN card, either of which point to your credit history, and allow a credit check to be completed.