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You can file your taxes online in Canada with CRA-certified software, sent through a service called NETFILE. For the 2025 return it opened on February 23, 2026 at 6:00 a.m. Eastern and stays open until January 29, 2027. The deadline to file was still April 30, 2026 for most people, so being open doesn’t mean being late is fine.
How do you file taxes online in Canada?
You pick certified software from the CRA’s list, enter your slips and answers, and send the return from inside the program. You don’t fill in a form on a CRA page. The software does the arithmetic and transmits the result, and once it says the return was received, you’re done.
Inside the software you can usually choose how the numbers get in, send the return and later read your notice of assessment. If you’ve filed before, the CRA account is the part that saves time, since slips from employers and banks can often be pulled in from it and you don’t have to retype a single box, which is where most typos come from.
What do you need before you start?
Gather your T4, T4A and other slips, and receipts for anything you plan to deduct. Check that the CRA has your current address, phone, email, name and marital status. Payments and letters follow those details.
The CRA’s get ready page also mentions an 8-character access code, found on your most recent assessment. Keep last year’s notice handy.
And log in to your CRA account well before deadline week, because a locked account on April 28 is a bad afternoon.
Dates and limits that matter
| Item | Detail |
|---|---|
| NETFILE and ReFILE open | February 23, 2026 to January 29, 2027 |
| Years you can file with NETFILE | 2018 to 2025, initial returns |
| Amended returns with ReFILE | 2022 to 2025 |
| Filing deadline, 2025 return | April 30, 2026 |
| Filing deadline if self-employed | June 15, 2026 |
| Payment deadline for everyone | April 30, 2026 |
Is there a new sign-in step for online filing?
Yes, but not yet for this season. The CRA says a new authentication step for online filing starts on February 22, 2027, and that it’s optional in 2026. You can already sign in to your CRA account while filing to prove who you are, and the CRA recommends adding a backup multi-factor method to the account.
First-time filers have no CRA account history to authenticate against. The CRA says they can still file through an authorized representative. We’d set up or repair the account well ahead of the next season instead of learning the rules in April.
What will the tax come to?
Software hands you an answer without telling you if it’s sensible, so get a rough figure first. Take an Ontario worker with $60,000 of employment income. Our income tax calculator shows $8,320.50 of tax. With $8,000 withheld, the tax refund calculator shows $320.50 owing, and a $3,000 RRSP deduction turns that into a $433.28 refund.
If your return looks nothing like that, check your slips. Twice. For self-employed people the numbers run higher. The self-employed tax calculator shows income tax plus both halves of CPP, though it leaves out EI and business expenses.
Mistakes when filing online
Sending the return and never reading the notice of assessment. Using an old version of the software (the CRA says to check the developer’s site for the latest update). Filing on time but leaving the balance unpaid, which stops the late-filing penalty and not the interest. And choosing software on a promise of “free” without checking what your forms need. We couldn’t confirm any price, so see our guide to free income tax filing before you pay for anything.
Where the numbers come from
Dates, NETFILE coverage and the security notice come from Canada Revenue Agency pages read in September 2026. The dollar figures are ours, from calculators that use 2026 federal and Ontario data, so they will not match a 2025 return exactly. We’re not connected to the CRA.
Frequently asked questions
When does NETFILE open?
For the 2025 return it opened on February 23, 2026 at 6:00 a.m. Eastern. It stays open until January 29, 2027.
Which years can I file online?
Initial returns for 2018 to 2025 can go through NETFILE, and amended returns for 2022 to 2025 through ReFILE.
Do I need a CRA account to file online?
Signing in to your account while filing is optional this season. From February 22, 2027 the CRA plans a new authentication step.
Where do I find my access code?
The CRA says it is 8 characters and printed on your most recent notice of assessment.
Does filing online change the deadline?
No. The 2025 deadline was April 30, 2026, or June 15, 2026 if you or your spouse or common-law partner were self-employed, with any balance due April 30.
- How Canadian income tax works: brackets and credits
How federal and provincial Canadian income tax stack up, what marginal and average rates mean, and how credits and deductions change your bill
Information only. This page is general information, not tax, legal or accounting advice. Tax-Services.ca is an independent publisher: we don't prepare or file tax returns or offer tax services, and we have no connection with the CRA, Revenu Québec, any government or any company named on this page. Check the figures that matter with an official source or a qualified professional.