All businesses with annual sales of $30,000 or more are required to have a Business Number (BN) or GST/HST number. This number indicates that the company has registered with government and that information on the company ownership is on file.

If you are hiring a professional contractor to work on your home, your contract should show the company's BN or GST/HST number. Any contractor who cannot provide you with this number either does very little work each year, or is operating illegally.