You can register directly on Ownr by clicking on 'Organization' and then 'Company Info':
You can also register directly online with the Government of Canada for GST/HST.
After you register, you must begin charging GST/HST to your clients.
Already have an old GST/HST Number?
If you already have a GST/HST number for your Sole Proprietorship or Partnership, you'll need to get a new account now that you've incorporated.
This is because your old GST/HST number is attached to you as a sole proprietor / partnership.