CRA Change My Return Explained
How CRA Change my return works in My Account, step by step.
The short version
- Change my return is CRA's online service, inside My Account, for fixing a return you already filed.
- It reaches back ten previous calendar years, and it doesn't matter whether you filed on paper or online.
- Wait for the notice of assessment first. Routine changes are usually processed in about two weeks.
- You usually don't send receipts unless CRA asks, but keep them ready.
- Not for loss carrybacks, certain elections or bankruptcy years. Those go on paper.
CRA Change My Return Explained
Change my return is the tool for people who filed on paper, used a preparer, or switched tax software since. You sign in to My Account, pick the year, pick the line, type the new number, and send it. CRA's system walks you through the common changes, like adding a slip or claiming a credit you missed.
Filed with software for a recent year? ReFILE does the same job from inside the program. Both are compared on how to change a tax return after filing.
Step by Step
- Sign in to CRA My Account. If you're not registered, do that first; a security code may come by mail.
- Find Change my return under the tax returns section, and pick the year.
- Choose the line to change. You'll need the line number; your copy of the return or your notice of assessment has it.
- Enter the corrected amount (the new total for the line, not just the difference) and a short reason.
- Submit and keep the confirmation number. The progress tracker shows when it's done, and a notice of reassessment follows.
Lines People Change Most
| What you missed | Line |
|---|---|
| A late T4 | 10100 employment income, 43700 tax deducted (plus CPP and EI lines) |
| Interest from a T5 | 12100 |
| An RRSP contribution receipt | 20800 |
| Union or professional dues | 21200 |
| Child care expenses | 21400 |
| Medical expenses | 33099 (or 33199 for other dependants) |
| Donations | 34900, through Schedule 9 |
Not sure which line? The slip pages explain each box: T4, T5, T4A. For deductions and credits, see Canadian tax deductions and tax credits.
Which line do I change, and what's it worth?
Describe what you missed. The assistant gives you the line number, the amount to enter, and roughly how much the change saves at your marginal rate.
What Change My Return Can't Do
- Carry back a capital or non-capital loss (form T1A on paper).
- Make certain elections.
- Change a bankruptcy return, or a year before a bankruptcy.
- Reach back further than ten calendar years.
For those, mail form T1-ADJ (or the specific form required) with your supporting documents. Paper changes are usually processed in about eight weeks.
A Good Use: Claiming Credits for Past Years
Change my return is the easy way to go back for things you didn't know about: a medical expense claim, union dues that were on your T4 but never entered, or the disability tax credit once it's approved. Refunds are generally limited to the last ten calendar years, so the oldest year is the one to do first. The limits are all on how far back can you file taxes.
Change or Objection?
Change my return fixes your own mistakes. If CRA changed your return and you disagree, file an objection instead, before the deadline. A change request doesn't stop the objection clock. See notice of reassessment: what to do.
Waiting on a Change?
Sent a change and heard nothing? CRA aims for about 2 weeks on simple online changes and 8 weeks by mail, but anything it has to check can take months. Here is what to do when your CRA adjustment is taking too long, and when the wait means you should protect your objection deadline.
Fewer Changes Next Year
Every change request is something that could have been caught before filing. Return Check compares your slips with your return and flags missed deductions and credits before you send it.
Change My Return Questions
What is Change my return?
A CRA online service in My Account that lets you request changes to a return you already filed, whether you filed it on paper or online.
How far back can I use Change my return?
For the ten previous calendar years. Refunds from changes are generally limited to ten years.
How long does Change my return take?
Routine online requests are usually processed in about two weeks. Requests that need review take longer.
Do I need to send receipts with Change my return?
Usually not. CRA asks for supporting documents only if it needs them, but you should keep them ready.
What can I not change with Change my return?
Loss carrybacks, certain elections, and bankruptcy returns or years before a bankruptcy. These are requested on paper.
Sources: CRA, Changing a tax return; Change your tax return online; Making changes to your tax return (2026). Checked October 2026. Menu names in My Account change from time to time.
Last reviewed October 11, 2026 against CRA and Government of Canada sources. How we check our facts.