When Do You Have to Register for HST? The $30,000 Rule Explained

If you're running a business in Canada, you've probably heard that you need to register for HST once you hit $30,000 in revenue. That's true — but the details matter a lot, and getting them wrong can cost you.

The Basic Rule

You are required to register for HST once your taxable revenues exceed $30,000 in any single calendar quarter, or in four consecutive calendar quarters. The moment you cross that threshold, you are legally required to register and begin collecting HST — not when you file, not at year-end, but from the date you exceeded the limit.

How to Count the $30,000

This is where most people get confused. The $30,000 applies to your taxable revenues — not your gross income, not your profit, not what you deposited into your bank account. Taxable revenues include all sales of taxable goods and services, before expenses.

A few things that count toward the threshold:

• Freelance or consulting income
• Sales of goods (products, inventory)
• Rental income from commercial property
• Revenue from most services provided in Canada

A few things that generally do NOT count:

• Employment income (T4 wages)
• Most residential rental income
• Exempt supplies (certain health services, financial services)
• Zero-rated supplies (most exports, basic groceries)

The Two Tests You Need to Know

Test 1 — The Calendar Quarter Test

If your taxable revenues exceed $30,000 in a single calendar quarter (January–March, April–June, July–September, or October–December), you must register immediately. You have 29 days from the date you exceeded the threshold to register.

Test 2 — The Four Consecutive Quarters Test

If your revenues in the last four consecutive quarters total more than $30,000, you must register by the end of the month following the quarter in which you exceeded the threshold.

What Happens If You Miss the Threshold?

This is where it gets expensive. If CRA determines you should have been registered and collecting HST, they can assess you for the HST you should have collected — out of your own pocket, whether you collected it from clients or not. They can also assess penalties and interest going back to the date you should have registered.

In practice, this means if you billed a client $10,000 for services when you were already over the threshold, CRA can come back and say you owe $1,300 in HST (13% in Ontario) that you never collected. That comes out of your revenue, not your client's pocket.

Should You Register Voluntarily Before $30,000?

Yes — in many cases. If you have significant business expenses (equipment, software, professional fees, rent), voluntary registration lets you claim Input Tax Credits (ITCs) and get the HST you paid on those expenses back. For a new business with startup costs, this can mean a meaningful refund in your first year even before you've hit the revenue threshold.

The downside: you now have to charge HST on your invoices, which adds administrative complexity and may make you appear more expensive to clients who can't claim ITCs themselves (like individual consumers).

Filing Frequency

Once registered, CRA assigns you a filing frequency based on your revenue:

• Under $1.5M annually — annual filer
• $1.5M to $6M — quarterly filer
• Over $6M — monthly filer

You can request to file more frequently than required if you consistently receive HST refunds — this gets your money back faster.

The Quick Method — Worth Knowing

If your taxable revenues are under $400,000 annually, you may be eligible for the Quick Method of accounting for HST. Instead of tracking every ITC individually, you remit a flat percentage of your total revenues to CRA and keep the difference. For service businesses, this often results in lower net HST payments. It's worth modeling before you elect.