Changing / Amending Your Income Tax Return
If you've filed your return and then determine that you need to make a change, either because you have received another T-slip, or because you didn't claim an expense and later learned it was deductible, you can request an adjustment to your tax return. However, wait until you get your Notice of Assessment (NOA) from Canada Revenue Agency (CRA) before making any changes.
The time limit for filing most adjustments to your tax returns by mail is ten (10) years. For a late or amended pension splitting election the time limit is three (3) years - see our Pension Splitting article.
You can request the change for your most recent return, or your returns for the previous 9 tax years, either online or by mail. In 2022, you can request a change for the 2012 or later taxation years.