Swapping the SIM card from one to the other will work, especially if going from nano to nano size as you would be if going from iPhone 5 to a newer iPhone.
If you ever need to amend the sizing, you can also get adapters from local mobile merchants who would likely have drawers full of them. (or snap off the outer adapters if going to a smaller size)
If you DON'T have the old phone (and the SIM card that was in it), you'd need to purchase another PM SIM card (TELUS, Koodo, or Mobile Klinik location or through Amazon or on this site under SHOP tab) and use the Change SIM card function in your self-serve account to retain the number/account on the new device.
