• ONLINE - If you are using the online version of the software, you simply go back to the side bar on the left (black section) - click on "My Info" then go down to "Your name Personal Info", you will be able to change your SIN number there.
• DOWNLOAD - Easy Step - If you are using the downloaded version - starting in "Easy Step" mode - once you get past the introduction section you will get to "Personal Info" page and you will be able to change your SIN# there. 
• DOWNLOAD FormsView -If you choose to use the "Forms" View - you must first enter your  personal information to be able to access "Forms" then you will be able to go to the top of the page in "Forms"view and click on "View" then go to the dropdown and click on "Personal Information" to change your SIN# there.

Please note that once you have Netfiled your return you will not be able to change your SIN, until you receive your Notice of Assessment to file an adjustment. Please review the link provided for more details on how to change a filed return.

• I have filed my tax return. Can I still make changes? https://turbotax.community.intuit.ca/community/tax-return-amendment/help/i-have-filed-my-tax-return-...

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