How do I change a return that's already been assessed?

Once you've filed your income tax return, you have to wait until you’ve received your notice of assessment from the Canada Revenue Agency (CRA) if you need to make any changes.

There are three ways that you can make changes to your federal tax return, after you have received your notice of assessment:

• Use H&R Block's ReFile functionality
• Log into My Account on the CRA website, and under the Tax returns section, click the Go to Tax returns link. Under Related services, click Change my return.
• Complete form T1 : Adjustment Request form (T1-ADJ) and send it to your local tax centre
• Write a letter to your local tax centre, containing all of your personal information and the details you need to change (tax year, amount, reason)

Note: If this is your first year filing a tax return, you won’t be able to use the services typically available through the CRA My Account; this is because the CRA requires that you file one tax return before you can register for their My Account service.

There are three ways that you can make changes to your Québec tax return:

• Use H&R Block's ReFile functionality
• Complete form TP-1.R-V : Request for an Adjustment to an Income Tax Return and mail it, along with the details you need to change (tax year, amount, reason) to Revenu Québec
• Use the Request to Change Income Tax Return Information service online

• How to change your return (CRA website)
• Changing an income tax return that you have already filed (Revenu Québec website)
• What is ReFile? (H&R Block's Online help centre)