Updated Checked by the Tax-Services.ca editorial team How we check
An online tax return in Canada goes through tax software the CRA has certified for NETFILE. Your 2026 return is due April 30, 2027, and the CRA's September 2026 tax tip points to a filing season beginning February 22, 2027. Returns for 2018 to 2025 can still go in online until January 29, 2027.
How do you file an online tax return with certified software?
You pick certified software, enter your slips and claims, and send the return through it. There’s no separate CRA form to fill in on the web. The CRA certifies third-party programs each year and publishes the list, which for 2025 shows 17 providers. Some run in a browser, some install on a computer, and some are phone apps. The CRA’s page on tax software for filing personal taxes explains the process and shows the service dates.
We won’t name a favourite, because prices change every season. The choice comes down to how simple your return is, how much help you want with the tricky parts, and what the provider charges. Read the free-version terms before you start typing. Eligibility rules differ.
In practice the steps run like this:
- Set up your CRA My Account if you haven’t, so your slips can come in automatically.
- Gather what’s left: receipts, RRSP slips, tuition forms.
- Choose certified software that fits your return.
- Enter your information, or use Auto-fill to bring in what the CRA already has.
- Read the summary page, then send the return.
- Save the confirmation number and a PDF copy.
What is Auto-fill my return?
It’s a CRA service that fills parts of your return with information the CRA already has. You need access to a CRA My Account to use it. Set the account up before you sit down to file.
Do you have to trust it blindly? No. Check every figure against your own slips. If your T4 says one number and the auto-filled line says another, find out why before you send anything.
| Item | What the CRA says |
|---|---|
| NETFILE and ReFILE open | 23 February 2026, 6:00 a.m. Eastern |
| NETFILE and ReFILE close | 29 January 2027 |
| Years you can file online | 2018 to 2025 first returns; ReFILE for 2022 to 2025 amendments |
| Refund with direct deposit | About two weeks online, up to eight weeks by mail |
| 2025 return due | 30 April 2026 for most people |
| 2026 return due | 30 April 2027 for most people (usual date, not yet printed by the CRA) |
Is it worth checking the numbers before you file?
Yes, and it takes ten minutes. Run your income through the income tax calculator first. On $60,000 in Ontario it shows $8,320.50 of 2026 income tax. If your software shows something wildly different, one of you has a wrong input.
Then try the tax refund calculator with the amount on your T4’s tax box. On $75,000 of Ontario employment income with $14,000 withheld, it estimates a 2026 refund of $1,295.35. It won’t match your return to the dollar, since it ignores many credits. But it tells you whether a big refund or a big bill is coming.
If you’re self-employed, the self-employed tax calculator gives a rough total of tax and CPP. It leaves out EI and GST/HST.
What if you already filed and spot a mistake?
Don’t panic, and don’t file a second return. The CRA’s online route for changes is ReFILE, which according to the same page handles amended returns for 2022 through 2025. Say Lena in Moncton finds a T4A she forgot after she sent her return in March. She amends the same year’s return and adds the slip, rather than hoping nobody notices. Fixing it yourself looks far better than waiting for a letter.
What goes wrong with online filing?
Typing errors top the list. A slipped digit in a box number changes your tax, and software won’t always catch it, so read the summary page before you submit and keep a PDF of the return and the confirmation number afterwards.
Next, picking the wrong tax year in the software. Match it to the return you’re actually filing, especially if you’re catching up on an old one.
The balance is another trap. Filing online doesn’t move the payment date. For the 2025 return, tax owing was due 30 April 2026 even if a self-employed person had until 15 June to file. Missing it starts interest, and filing late can trigger a penalty of 5% of the balance plus 1% per full month, up to 12 months, according to the CRA’s page for that year.
Last, forgetting to save a copy. At tax time you’ll be glad you did, and next year’s return gets easier when you can look back at this one.
Where the numbers come from
Service dates, filing years, refund times and penalty rates come from Canada Revenue Agency pages read in September 2026. Example taxes come from our calculators, which use 2026 federal and Ontario rates. We make no claims about the price or features of any software product. This site is independent of the CRA.
What should you prepare for the 2026 filing season?
Set up or repair your CRA account now, add a backup sign-in method, and check that your address and direct deposit details are current. The CRA says authenticating when you file is optional for the 2026 return, and its tax tip explains why it is adding the step.
Then collect slips as they arrive. T4 and T4A slips are due by the end of February, and our documents checklist lists the rest. Before you file, run your income through the tax refund calculator so you know whether a refund or a bill is coming, and read when you will get your refund.
Where we checked
Service dates, filing years, refund times and penalty rates come from the CRA's NETFILE overview, late-filing penalty page and tax tip on online filing security, read in November 2026. Example taxes come from our calculators, which use 2026 federal and Ontario rates. We make no claims about the price or features of any software product. This site is independent of the CRA.
Frequently asked questions
How do I file an online tax return in Canada?
Use tax software certified by the CRA for NETFILE. You enter your slips and claims in the program and send the return from there. There is no separate CRA form to fill in on the web. Save the confirmation number and a PDF copy when you finish.
When is the 2026 return due?
April 30, 2027 for most people. If you or your spouse are self-employed you have until June 15, 2027 to file, but any tax owing is still due April 30, 2027. The CRA had not printed these dates for 2026 returns when we checked, so confirm them on its site.
Until when can I file an older year online?
NETFILE takes initial returns for 2018 to 2025 and ReFILE takes amended returns for 2022 to 2025, both until Friday, January 29, 2027. The 2026 return is a separate filing in 2027, due April 30, 2027 for most people, so pick software certified for the right year.
How fast is a refund when I file online?
The CRA says about two weeks with direct deposit, against up to eight weeks for a paper return sent by mail. Times can be longer if your return is reviewed. Check your notice of assessment in your CRA account for the result.
Do I need a CRA account?
You need one for services like Auto-fill my return, which uses information the CRA already holds. For the 2026 return, signing in when you file is optional, according to the CRA. First-time filers with no account can still file through NETFILE.
- How to file your tax return in Canada: steps and dates
What to gather, when your return is due and how to file in Canada, from the first slip to the notice of assessment that closes the year