If you are already registerd for GST, no further registration is required. Your first HST return is due at the same time that your old GST return would have been due. HST will save businesses over $500 million a year in administrative and compliance costs alone.
Harmonized Sales Tax
The 13% HST came into effect on July 1, 2010 in Ontario.
What is HST?
Is it mandatory to register for a HST number?
If your taxable sales are more than $30,000 and they are not exempt from HST, you must register. If your sales are less than $30,000, you have the option of registering. Registering is generally a good idea since you can then claim input tax credits in respect of your expenses.