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When a business model transformation changes how you earn, three accounting questions come up straight away: do you now have to charge GST/HST, how is the income taxed, and does the structure still fit? The first has a hard number. You must register once your taxable revenues pass $30,000 in a single calendar quarter or across four consecutive quarters.
When does a new revenue stream trigger GST/HST?
A side business, a new product line or an online shop counts toward the same total. The CRA’s small supplier rule looks at your worldwide taxable revenues, before expenses, including those of associated businesses. If you’re at $30,000 or under in every quarter and over the last four quarters together, you can stay unregistered. The CRA’s general information for GST/HST registrants gives the definition in full.
Cross the line and the clock runs fast. You charge the tax on the sale that took you over, even before you’re registered, and you register within 29 days after you stop being a small supplier. That surprises people who thought the line was a year-end check.
A quick timeline: say Nadia’s new online course business goes over $30,000 with a sale on June 10. Tax applies from that sale, and her 29 days run out on July 9. If she waits until September, she’s late, and she still owes the tax on every sale since June 10, whether she charged it or not.
Registering before you hit the line is allowed, but the rules for doing it early are worth reading on the CRA’s registration page first. You can work out the tax on any sale with the GST/HST calculator.
What does a business model transformation do to your income tax?
It moves you from a payslip, where the employer handled everything, to a return where you do. Net business income is taxed at your normal rates, and you pay both halves of CPP.
Here’s the size of it. On $80,000 of net business income in Ontario, the self-employed tax calculator shows $13,233.57 of income tax and $8,892.90 of CPP, so $22,126.47 in total and $57,873.53 left. That figure leaves out EI and GST/HST, and the tool lowers income tax for deductions but not CPP, so read it as a starting point.
Do you have to pay during the year? You may, and the tax instalments calculator shows what to set aside each quarter. Even a ballpark figure beats finding out in April how much the taxman wants.
Is it time to incorporate?
Only sometimes, and not because it’s the grown-up thing to do. A corporation is taxed separately, and money taken out to you is taxed again. The federal rate on a Canadian-controlled private corporation’s first $500,000 of active business income is 9%, against 15% on the general rate. On $120,000, the corporate tax calculator shows $10,800 of federal tax. Provincial tax is added on top, and our provincial rates for 2026 are estimates, so they aren’t quoted here.
| Structure | What changes |
|---|---|
| Sole proprietor | Business income goes on your own return, taxed at personal rates |
| Corporation | Files its own T2, electronically for tax years starting after 2023 |
| Corporation, paying yourself | Salary or dividends are taxed in your hands as well |
Corporate tax isn’t the whole cost. A corporation adds a T2 every year, with a $1,000 CRA penalty if a required return isn’t filed online, plus the payroll remittances if you pay a salary. Use the dividend tax calculator to see what comes out again when you pay yourself.
What should you do in the first month after the change?
Three small things. Start one running total of taxable sales across every line of business, so the quarter-by-quarter test is a glance and not a research project. Open a separate bank account for the new stream if you haven’t, since mixed money is the fastest way to lose track of what counts. And set up a short chat with your accountant (a third party, not us) before your first quarter ends, not after the first tax bill.
What goes wrong in a transformation?
Mostly timing. Picture a model change in March, $30,000 crossed by June and a registration filed in September: that’s a late registration. Or the old books stay in one tool, the new revenue lands in another, and nobody can see the combined quarter total that the GST/HST rule measures.
So keep one record of taxable sales across every line of business. Keep it for six years too, since that’s the CRA’s retention period.
And don’t read one calculator as the decision. They show the tax, not the legal, insurance or liability side of incorporating, which this page doesn’t cover.
What this page is based on
The small supplier rule is from the CRA‘s GST/HST registration pages. The federal corporate rates and the $500,000 limit are from the CRA’s corporation tax pages and T2 guide. Income tax and CPP figures are from our calculators on 2026 rates. No level of government runs or endorses this site.
Frequently asked questions
At what income must I register for GST/HST?
When your taxable revenues pass $30,000 in a single calendar quarter or over the last four consecutive calendar quarters. Associated businesses count toward the total.
Do I charge GST/HST before I register?
You charge it on the sale that took you over $30,000, then you register within 29 days after you stop being a small supplier.
Does incorporating always lower my tax?
No. The corporation pays its own tax, and money you take out is taxed again in your hands. The result depends on how much you keep in the business.
What is the federal small business rate?
9% on the first $500,000 of active business income for a Canadian-controlled private corporation, per the CRA T2 guide. Provincial tax is extra.
Do corporations file their T2 online?
For tax years starting after 2023, yes, with listed exceptions. The CRA charges $1,000 when a required electronic filing isn't made.
- Self-employed taxes in Canada: income, CPP and GST
How tax works when you are self-employed in Canada: reporting income and expenses, paying both halves of CPP, instalments and when to register for GST