To be able to use tax codes for other provinces that your business buys from or sells to.

When setting up your business information, you should be allowed to pick which provinces that you do business in, so the proper taxes are used. For example in my case my farm is in Quebec but we border Ontario. All the farm dealers are in Ontario,and there is only one local elevator (Quebec side),but serveral close by in Ontario. My grain gets sold in Ontario and when entering the invoice into the system, it deposits the wrong amount into my bank account.