When does my new Ontario business need to register for HST?

You must register for HST as soon as your worldwide taxable revenues (including zero-rated) exceed $30,000 in any four consecutive calendar quarters or in a single quarter. This is the small supplier threshold in Excise Tax Act s. 148. Voluntary registration under s. 240(3) is available from day one and is often the better choice.

Trigger date matters. You have 29 days from the day you cease to be a small supplier to register (ETA s. 240(1)). The supply that pushed you over is itself taxable; you owe HST on that supply and on every taxable supply thereafter, whether or not you invoiced it.

Example: an Ontario freelance designer bills $8,000 per month starting April 2026. By the end of Q4 2026 cumulative revenue is $72,000. The July invoice is the one that pushed cumulative four-quarter revenue over $30,000. Registration is required within 29 days of that invoice date; HST must be back-charged (or absorbed) from that invoice forward.

Voluntary early registration is worth considering when: you sell primarily to registered businesses (they recover the HST as ITCs), you have significant startup HST-taxable expenses (you recover them as ITCs from day one), or you want a professional-looking invoice from the start.

Note: A taxi or ride-share driver is deemed to be a registrant from day one regardless of revenue (ETA s. 240(1.1)). A non-resident selling digital services to Canadian consumers may also face a lower threshold under the simplified regime.

Source: canada.ca — When to register for a GST/HST account

— Bader A. Chowdry, CPA, CA, LPA — Insight Accounting CPA

Disclaimer: Bader A. Chowdry, CPA, CA, LPA is a Licensed Public Accountant regulated by CPA Ontario. Insight Accounting CPA Professional Corporation is a Chartered Professional Accountant firm. This content is general information only and does not constitute professional advice for your specific facts. Confirm current rules and figures with your own advisor before acting.