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A small business tax accountant earns their fee in two places: getting your deductions right and telling you when a change of structure would help. On an $80,000 profit in Ontario, a sole proprietor pays $22,126.47 of income tax and CPP. So the first job is to know that number and then see what the accountant can move.
What does a small business tax accountant do that software doesn’t?
Software records what you type. An accountant questions it, and that difference is most of what you pay for when a return gets checked months later by someone who wasn’t in the room when you made the purchase. They’ll ask why a personal trip sits in travel, whether a vehicle claim matches a logbook, and whether that $4,000 purchase is an expense or an asset.
They also decide the return type. A sole proprietor reports on the personal return with form T2125, due June 15, with any balance due April 30. A corporation files a T2 within six months of year end. Each has different paperwork, and the wrong start is costly to undo.
What is a good expense claim worth?
Here’s a plain example. Your business nets $80,000 in Ontario. The self-employed tax calculator gives $13,233.57 of income tax and $8,892.90 of CPP. Find another $10,000 of legitimate expenses and profit drops to $70,000. Tax and CPP fall to $18,298.32, so you keep $3,828.15 more.
That’s the upside of careful books: $3,828.15 on $10,000 of expenses means each real dollar you claim saves about 38 cents. The downside runs the other way. A claim the CRA rejects for lack of proof costs you the tax back plus interest.
| Net profit (Ontario) | Income tax | CPP, both halves | Total |
|---|---|---|---|
| $70,000 | $10,384.82 | $7,913.50 | $18,298.32 |
| $80,000 | $13,233.57 | $8,892.90 | $22,126.47 |
The calculator leaves out EI and GST/HST, and it starts from profit after expenses.
What should you bring to the first meeting?
Last year’s return, a year of bank statements, your sales invoices and the receipts for anything big. Add a short list of what worries you. Jordan, who does renovations in Saskatoon, brought a truck mileage log and a pile of unlabelled receipts, and the accountant sorted out the vehicle claim in one sitting. Ask what they want in a digital format so you don’t scan paper twice. The CRA page on keeping records explains how long you need to keep it all.
When does incorporating come up?
Usually once profit outgrows what you need to live on. Put the same $80,000 through a Canadian-controlled private corporation in Ontario and the corporate tax calculator shows $9,356.80, an 11.7% rate. Compare it carefully, though. That’s tax inside the company, and paying yourself out triggers personal tax, which the dividend tax calculator estimates. Ontario’s 1 July 2026 rate cut also makes the 2026 rate a blend we derived, not a published number.
So it’s not a comparison of $22,126 against $9,357. A fair answer needs your salary, dividends and how soon you need the cash, which makes it a good use of an accountant’s hour. Incorporating also brings a T2 every year, and costs that come with it.
What should you ask before you hire?
Ask how many owner-managed businesses they file for, and which professional body they belong to, so you can check its register. Ask whether the quote includes bookkeeping, payroll and CRA letters. We couldn’t confirm what accountants usually charge, so don’t trust a fee comparison from anyone who won’t show a quote.
Ask too what they need from you and when. If you hire staff, the payroll remittance calculator shows the amounts they’ll be tracking.
Is it worth paying for advice if your books are simple?
Often yes, once a year. A one hour review before year end can tell you whether your structure, your instalments and your records still fit. Skip the monthly retainer until your business is complicated enough to need it. If your only income is one client and a handful of expenses, good software and this page may be all you need.
Where do small owners lose money?
- Missing instalments, then paying interest on a bill that grew all year.
- Claiming the home office without measuring the space.
- Paying themselves with no plan for the tax on it.
- Deducting personal costs, which the CRA can disallow with interest.
- Waiting until year end to ask whether the structure still fits.
Where we got these figures
Deadlines are from Canada Revenue Agency pages on 2026 business tax deadlines and on when to file a corporation return, read in September 2026. The federal small business rate of 9% on the first $500,000 comes from the CRA’s corporation tax rates page. Personal figures use 2026 federal and Ontario schedules. No government body has reviewed or endorsed what you read here.
Frequently asked questions
What does a small business tax accountant do?
They file your return, check your claims against your records and advise on structure, such as staying a sole proprietor or incorporating.
How much do accountants for small businesses charge?
We couldn't confirm typical fees from an official source. Get a written quote that says what's included.
Do I need an accountant if I'm a sole proprietor?
Not always. If your books are simple you can file with software, but an accountant helps when expenses, a vehicle or a home office are involved.
How much tax is due on $80,000 of self-employed profit?
In Ontario the calculator shows $13,233.57 of income tax and $8,892.90 of CPP, $22,126.47 in total.
Is incorporating cheaper?
Tax inside the company is lower, 11.7% on $80,000 in the calculator, but you pay personal tax when you take money out.
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