Does it matter where my business is located or where my customer lives when charging HST on services?

For most services, it's generally the customer's location, more precisely, the address connected to the supply that's obtained in the ordinary course of business, that determines which province's GST/HST rate applies, not where your business happens to be based. A service business physically located in Ontario can still be required to charge a different province's rate, or plain 5% GST with no provincial component, if the customer and the supply are properly connected to a non-HST province instead.

This trips up a lot of Ontario-based service providers who assume that being physically located and registered in Ontario means every invoice automatically carries 13% HST. Where the customer's information ties the supply to a different province, that province's rate is generally the correct one to charge, and applying Ontario's rate instead can mean the wrong amount was collected and remitted.

Because the specific rules for identifying the relevant customer address, and the tie-breaking rules when a customer has connections to more than one province, vary by the type of supply involved, don't assume your own business address controls the rate, confirm the correct place-of-supply analysis for your particular services and customer base with a tax advisor.