If you do not agree with a decision made by the Canada Revenue Agency, you may file a notice of objection. You can file objections to income tax assessments, as well as to determinations on tax credits or benefits.

Filing a Notice of Objection

If you believe the CRA has made a mistake, applied the law incorrectly or misinterpreted the facts, you may file a notice of objection online or by mail.

To file online, individuals can use the My Account online service by selecting Register My Formal Dispute. Similarly, businesses may use My Business Account online service. Alternatively, you can complete Form T400A and submit it to your nearest tax centre by mail.

Time Limits

If you are an individual and want to object to an assessment on your income tax return, you have one year from the filing deadline for this return to do so.

However, if you are objecting to the assessment of taxes based on over-contribution to your Registered Retirement Savings Plan or Tax-Free Savings Account, you only have 90 days to file your objection. Similarly, if you are objecting to information on a notice of assessment, you have 90 days to file.

For example, if the CRA rejects a medical expense you claimed, your income will be adjusted accordingly and the CRA will increase the tax you owe. However, if you disagree with the CRA’s decision, you have one year from your filing deadline to object.

In contrast, if you submit an application for the Disability Tax Credit and the CRA rejects your application, you have three months to file a notice of objection for this determination.

Requesting an Extension

If circumstances beyond your control prevent you from filing a notice of objection before the applicable deadline, you can request an extension.

You can make this request online through the CRA’s My Account or My Business Account services. You can also do so by writing to the Chief of Appeals at your Appeals Intake Centre.

You may request an extension to file your notice of objection for up to one year after the deadline.


After you file a notice of objection, the CRA will make a final decision about the matter in question. If you disagree with the CRA’s final decision, you can appeal to the Tax Court of Canada.

You must do this within 90 days of receiving the reply to your notice of objection. If you disagree with the Tax Court’s decision, you may be able to take your complaint to the Federal Court of Appeal or the Supreme Court.

Your Tax Owed

If you owe tax on an amount that is being disputed, you do not have to pay tax on this amount until the matter is settled. If you have already paid tax on this amount, you may request to have it returned to you. However, if the courts assess that you owe the money, you will also be required to pay interest on it.

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