CRA Notices, Reassessments & T1 Adjustments
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Frequently asked questions
What is the difference between an adjustment and an objection?
An adjustment (Change My Return, ReFILE, or a paper T1-ADJ) is how you correct your own return — a missed slip, a math error, a deduction you forgot to claim. An objection (Form T400A or a signed letter) is the formal process for when you disagree with a decision CRA already made after reviewing your return. Adjustments are faster and don't require you to prove CRA was wrong.
How long do I have to object to a CRA reassessment?
Generally the later of one year from the filing deadline for the tax year, or 90 days from the date on the Notice of Assessment or Reassessment. Missing this deadline can mean losing the right to object, though a late filing may sometimes be accepted with a valid reason.
Does arrears interest keep compounding while I dispute a reassessment?
Yes. Filing an objection does not pause arrears interest on a disputed balance — CRA continues compounding daily at the prescribed rate. Paying the disputed amount (or as much as you can) while the objection is reviewed limits the interest cost even if you are ultimately right.
Can I still use ReFILE if my return has already been reassessed?
It depends on the change. ReFILE works for many corrections through certified tax software, but some changes — including corrections after a reassessment is already underway, bankruptcy-year returns, or certain carryback requests — require Change My Return through CRA My Account or a paper T1-ADJ instead.