Obtain the proof of ownership you will need to register the trailer. When you buy the trailer, be sure to get a bill of sale. If you are leasing the trailer, you will need the lease agreement.
Get the trailer inspected by a licensed Alberta inspection technician, if you don't have a valid inspection certificate.
Go to an Alberta Registry Agency. Trailer registration is not available online. There are registry agents in most towns and cities in Alberta, often in insurance agencies. AMA (Alberta Motor Association) also provides registry services to its members.
Present proof of ownership, inspection certificate, valid identification (such as an Alberta Driver's License) and any support documents requested by the registry agent.
Pay the agent. For commercial trailers, the cost in October 2010 ranged from CDN $203 to CDN $2,033 (about USD $197 to $1,968), depending on the weight of the trailer, with an additional processing fee of up to CDN $9.
Affix the license plate to the back of the trailer. Carry the trailer registration inside the semi hauling the trailers.