If you are a business that does online sales have to collect and remit taxes just the same as if you had a bricks and mortar business. This means that you will need to charge and remit other province's sales taxes and different rules in different provinces can make this process complicated.
Businesses need to register as a provincial sales tax vendor with each province where they will be doing business. Unfortunately, there is little that can be done get around this additional paperwork and bookkeeping, except for to limit the provinces where you ship goods, for example if businesses only sell products to consumers in their own province or if they only sell non-taxable goods and services.
Provincial sales taxes vary by province. There is also the goods and services tax and some provinces use the harmonized sales tax which combines the GST with their provincial sales tax. For businesses selling only within their own province or territory they only need to follow the rules for their province, but for those selling to other provinces they must charge taxes according to the rules in those provinces.
From an article by Susan Ward
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