You can make a formal objection if you disagree with the amount of tax, interest, or penalties the CRA has assessed or reassessed. You have 90 days from the date of the notice of assessment, or reassessment, to file the objection.
You can file an objection:
- online, using the “Register a formal dispute (Notice of Objection)” service
- by mail, using Form T400A, Notice of Objection – Income Tax Act, or writing to the chief of appeals at your Appeals Intake Centre