Updated Checked by the Tax-Services.ca editorial team How we check
Tax technology in Canada, for a small business, comes down to one rule and a handful of CRA services. For tax years starting after 2023, corporations have to file the T2 return electronically, using software the CRA has certified, unless they fall into a short list of exceptions.
What does the CRA make you file online?
The T2 corporation return. That’s the one with a hard rule. The CRA’s page on completing your T2 return lists four groups that don’t have to file online: insurance corporations, non-resident corporations, corporations that report in a functional currency, and corporations exempt from tax under section 149 of the Income Tax Act.
Everyone else files online, and a corporation that is required to file electronically and doesn’t faces a $1,000 penalty, according to the same CRA page. That’s a steep price for a paper envelope, so it pays to get the software sorted before the due date.
Which CRA services do the work?
You don’t buy these. They’re the pipes your software plugs into.
| Service | Who it’s for | What it does |
|---|---|---|
| Corporation Internet Filing | Corporations and their preparers | Receives the T2 that your certified software sends |
| My Business Account | Business owners | Secure access to your own business tax account |
| Represent a Client | Authorized representatives | Lets your accountant or bookkeeper act on your file |
| T2 Auto-fill | Optional, inside your software | Downloads CRA data into the return |
| T2 Attach-a-doc | Optional, inside your software | Attaches supporting documents to the return |
How do you pick tax software the CRA accepts?
Start with certification. The CRA certifies commercial software against its own specifications, and the T2 has to go through a certified product. Ask any vendor whether the T2 module is certified for the tax year you’re filing, and get the answer in writing.
Then look at the boring parts. Can you export your data if you switch? Can your accountant get in without sharing your password? Does it force you to pick a main business activity from a list? (The certified products do.) We haven’t compared products, and we can’t confirm prices, discounts or feature claims for any of them, so nothing here ranks a brand.
Where do AI tools fit into filing?
We couldn’t find a CRA statement about AI tools in filing, so we make no claim either way. The mechanical facts hold whatever you use: the return has to go through certified software, and you’re the one who signs it. A drafting tool can shape a question for your accountant. It can’t file for you.
Can you check the software with a calculator?
Yes, and once is enough. Take one employee paid $3,000 a month in Ontario. The payroll remittance calculator shows $502.42 held back from pay and an employer share of $229.61, so about $732 to remit each month. The full cost of that employee is $3,229.61 a month.
If your payroll software shows something quite different for the same pay, find out why before the first remittance. Small rounding gaps are normal, and CPP and EI stop at their yearly maximums, so the numbers shift late in the year.
Sales tax is easier. On a $100 sale in Ontario, the GST/HST calculator gives $13 of HST and a $113 total. And to see what the corporation itself owes, try the corporate tax calculator. On $100,000 of active business income in Ontario it shows $11,696, but that uses a blended 2026 small business rate that isn’t published as one number, so treat it as a ballpark. Employee pay works the same way in the payroll deductions calculator.
What should you set up before the filing season?
A few small jobs now save a scramble later. Make sure someone, you or your accountant, has access to your business account online. Decide who is authorized to represent the corporation, and set that up through the CRA’s representative service rather than sharing a login. Confirm your software is certified for the year you’re filing. And ask your accountant which supporting documents they’ll want, so you can collect them during the year and not in the last week.
It sounds fussy, but it’s the difference between filing the day your numbers are ready and filing the day you finally get a password reset.
What goes wrong with software filing?
Auto-fill is optional, and it’s only as good as the CRA data behind it. Read what it brings in.
Software that “completes” a return hasn’t filed it. The transmission is a separate step, and the CRA’s confirmation is what you keep. Also, a program can’t tell you which of your expenses are deductible. That still takes a person who read the rules.
And if your corporation is on the exception list, don’t assume the electronic rule is optional forever. We didn’t find a 2026 filing date on an official page, so check your own due date.
Where this information comes from
The filing rule, the $1,000 penalty, the exception list and the service names come from the CRA pages on the T2 return and tax preparation software, read in 2026. Payroll and sales tax figures come from the calculators on this site, which use 2026 CPP, EI and HST data. We’re not connected with the CRA or any software company.
Frequently asked questions
Do corporations have to file the T2 online?
For tax years starting after 2023, yes, with exceptions for insurance corporations, non-resident corporations, corporations reporting in a functional currency and those exempt under section 149.
What is Corporation Internet Filing?
It's the CRA service that receives a T2 sent from certified software. My Business Account and Represent a Client are the other ways in.
Is T2 Auto-fill required?
No. The CRA lists it and T2 Attach-a-doc as optional services inside your software.
Can AI software file my return?
We found no CRA statement on it. Any return still has to go through certified software and you sign it.
How can I test my payroll software?
Compare it with a calculator. One employee at $3,000 a month in Ontario should show about $732.02 to remit.
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