You can make changes (amendments) to your current tax return, whether you filed by mail or electronically. The Canada Revenue Agency (CRA), requires that you wait until you’ve received your Notice of Assessment (NOA) before filing an adjustment. In many cases, the CRA will catch the mismatch and automatically adjust your return for you. 

Below are some steps/tips that can help you make any changes (amendments) to your current tax return:

1. Visit the link at the end of this message that will take you to the CRA website on how to change a return
2. Follow the steps on the CRA website. You can change your return online or by mail. Online could take up to about 2 weeks, mail could take up to about 10-12 weeks.
3. If your return was electronically filed you may be able to ReFile it using TurboTax.

 Below are the links that will be able to guide you, thank you for using TurboTax.

CRA - How to change your return 

TurboTax - I have filed my tax return. Can I still make changes?