After you file

How Can I Amend My Tax Return?

There’s things you can’t change, like a bad haircut or a silly tattoo. Fortunately, if you’ve made an error on your tax return and need to amend it, there’s a fairly simple way to do so.

First of all, if you need to amend your tax return, do not file another return for that year.

You should wait until you receive your Notice of Assessment before requesting any changes to be made to your tax return. The general rule is that you can only ask for an amendment to be made on tax returns as far back as 10 years – so if there’s something that needs to be fixed in your 2006 return, you’re out of luck.

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There are two ways to request amendments to your tax return: online and by mail. There are rules and limitations for each one, and we’ll take you through them so you have a better understanding of which one to choose.

Requesting an Amendment Online

Being the easier option of the two, requesting an amendment to your tax return online simply requires you to log in to you CRA My Account and click “Change my return”. Do keep in mind that you cannot request an amendment to change any of the following:

  • a bankruptcy return
  • a tax return where 9 reassessments exist for a particular tax year
  • a tax return that has not been assessed
  • a tax return prior to the year of bankruptcy
  • carry-back amounts such as capital or non-capital losses
  • an elected split-pension amount
  • a return of an international or non-resident client (including deemed residents of Canada, newcomers to Canada, and individuals who left Canada during the year)
  • a return where you have income from a business with a permanent establishment outside your province or territory of residence

Request an Amendment by Mail

First, you will have to complete a T1-ADJ T1 Adjustment Request. You can download a PDF copy of it from the CRA’s website by clicking here. As an alternative, you can also submit a signed letter with the following details:

  • The years of the returns to be changed
  • Your social insurance number
  • Your full address
  • A telephone number where you can be reached during the day

Whichever option you choose, you’ll have to send all supporting documents for your amendment – including those for the original assessment, – to your tax centre (click here to find out which one is closest to you).

Processing Times

  • Within 2 weeks if requested online
  • Within 8 weeks if requested by mail

Processing might slightly longer if you your request is sent in spring or early summer, needs further review, or if the CRA has to contact you or your authorized representative for more information or documentation.

Once your review is complete, you will receive from the CRA either:

  • a Notice of Reassessment showing changes to your return
  • a letter explaining why the changes you asked for were not applied

All in all, you can retire any worries if you suddenly realize that you have to make changes to your tax return. Follow the instructions above and the process should be simple and easy.