As a GST/HST registrant, when am I required to start collecting HST on sales?

You are required to collect HST when your taxable sales (over the last 4 quarters) exceeds the $30,000 threshold. As a voluntary registrant, you need to collect HST on sales starting on the earlier of:

1. the effective registration date listed on your GST/HST account application,
2. the day of the supply (sale) that made go over the $30,000 threshold amount.

For example, if your effective registration date is August 1st but you made a sale on June 1st that caused you to exceed the $30,000 threshold, you will have to start collecting HST beginning with the sale that forced you to exceed the threshold.