Normally Canada Revenue Agency allows you to make an online adjustment for the 10 previous calendar years to help simplify your online adjustment submissions.
There are three ways to make amendments to your tax return: through CRA My Account, ReFile using your tax solution, or by mail. The CRA requires that you wait until you’ve received your Notice of Assessment (NOA) before filing an adjustment.
For further guidance please review our TurboTax FAQ: I've filed my tax return. Can I still make changes?
For more information, please see our TurboTax article: How Can I Amend My Tax Return?
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