Do I Need to Register for HST in Ontario? Thresholds Explained

Understand the CRA $30,000 small supplier threshold in Ontario, when mandatory GST/HST registration triggers, voluntary registration benefits, and filing frequencies.

taxes7 min readPublished August 8, 2026

The CRA $30,000 Small Supplier Rule in Ontario

In Ontario, businesses must collect and remit the 13% Harmonized Sales Tax (HST) once they exceed the Canada Revenue Agency (CRA) small supplier threshold.

Understanding when this obligation begins protects you from unexpected back-taxes and penalties.


When Is HST Registration Mandatory?

You are legally required to register for a GST/HST account with the CRA if your gross worldwide taxable supplies (sales before expenses) exceed $30,000 CAD:

  1. In a single calendar quarter: You cease to be a small supplier immediately. You must register and begin collecting HST on the sale that caused you to exceed $30,000.
  2. Over four consecutive calendar quarters: You cease to be a small supplier at the end of the month following the quarter in which you crossed the $30,000 mark.

Mandatory vs Voluntary HST Comparison

Factor Small Supplier (< $30k) Exceeding Threshold (> $30k)
Registration Status Voluntary Mandatory
HST Collection (13%) Do NOT charge unless registered Must charge and remit 13% HST
Input Tax Credits (ITCs) Only if voluntarily registered Eligible to recover HST on all business expenses
Filing Frequency Annual (typically) Annual, Quarterly, or Monthly

Advantages of Voluntary Registration

Even if your revenue is under $30,000, voluntary registration offers key benefits:

  • Input Tax Credits (ITCs): You can recover all 13% HST paid on business equipment, software, tools, legal fees, and supplies.
  • B2B Credibility: Corporate clients expect an HST number on commercial invoices.
  • Immediate Preparation: No risk of crossing the threshold unexpectedly and failing to collect tax.

Next Steps

Frequently asked questions

What is the small supplier revenue threshold for HST in Ontario?
The small supplier threshold is $30,000 CAD in gross worldwide taxable sales across any single calendar quarter or across four consecutive calendar quarters.
What is the HST rate in Ontario?
The Harmonized Sales Tax (HST) rate in Ontario is 13% (composed of a 5% federal component and an 8% provincial component).
Can I register for HST voluntarily if my revenue is below $30,000?
Yes. Voluntary registration allows you to claim Input Tax Credits (ITCs) to recover the 13% HST paid on business expenses, equipment, and inventory.

Official sources

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