If you are starting out, you don't need to register for a GST/HST number. If you don't, then you can't charge the end user tax. You will fall under the small supplier category.
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You do not have to register if:
- your only commercial activity is the sale of real property, otherwise than in the course of a business; or
- you are a non-resident who does not carry on business in Canada.
- Small supplier.
If you are a small supplier and do not have to register if you meet one of the following conditions:
- If you are a sole proprietor, your total revenues from taxable supplies (before expenses) from all your businesses are $30,000 or less in the last four consecutive calendar quarters and in any single calendar quarter.
- If you are a partnership or a corporation, the total revenues from taxable supplies (before expenses) of the partnership or corporation are $30,000 or less in the last four consecutive calendar quarters and in any single calendar quarter.
and
Voluntary registration
If you are a small supplier and you are engaged in a commercial activity in Canada, you can choose to register voluntarily, even though you are not legally required to do so. If you register voluntarily, you have to charge and remit GST/HST on your taxable supplies of goods and services, and you can claim ITCs for the GST/HST you paid or owe on purchases related to these supplies. You have to stay registered for at least one year before you can ask to cancel your registration. For more information, see Canceling your registration.
If you choose not to register, you cannot charge your customers GST/HST, and the GST/HST you pay on your business purchases becomes a cost for which you cannot claim ITCs.