How to File a CRA Notice of Objection in Ontario

If the Canada Revenue Agency has issued a reassessment you believe is wrong, the formal first step in fighting it is filing a Notice of Objection. This is your statutory right under the Income Tax Act — and it is the gateway to everything that follows, including an appeal to the Tax Court of Canada.

The CRA notice of objection process is not complicated, but it is deadline-driven and unforgiving. A late or incomplete objection can kill an otherwise strong case before it gets a fair hearing. This article explains what an objection is, how to prepare one, when to file it, and what happens next.

What Is a Notice of Objection?

A Notice of Objection is a formal written dispute telling the CRA you disagree with an assessment or reassessment. Filing one:

• Triggers a fresh review of your file by the CRA Appeals Division — a separate team from the auditors who produced the reassessment
• Puts the CRA on notice that you intend to dispute
• Starts the timeline for a possible Tax Court appeal if the CRA doesn't resolve the matter to your satisfaction

Until you file an objection, you have not formally disputed anything. Simply calling the CRA or writing a complaint letter is not the same as filing a Notice of Objection.

The Objection Deadline — Do Not Miss It

This is the most important practical point in this article.

As of writing, the deadline to file a Notice of Objection is generally the later of:

• 90 days from the date on the Notice of Assessment or Reassessment; or
• One year after the filing due date for the tax return in question

Verify this deadline immediately with the CRA or a tax professional. The deadline is statutory. Courts and the CRA treat it strictly — missing it by even one day can mean losing your right to dispute. The date that counts is the date CRA actually receives your objection, not the date you mail it.

What if the deadline has passed?

You can apply to the CRA for an extension of time to file an objection. This is not automatic — you must demonstrate that you applied as soon as circumstances permitted and that you had a bona fide intention to object within the original deadline. If CRA refuses your extension request, you can apply to the Tax Court. Get legal help quickly if your deadline has already passed.

What to Include in a Notice of Objection

There is no official CRA form required (though Form T400A exists and can be used for individual taxpayers). At minimum, a proper Notice of Objection must contain:

1. Your name, address, and social insurance or business number
2. The date of the assessment or reassessment you are disputing
3. The tax year(s) in question
4. A clear statement of the issues you are disputing — which line items do you disagree with?
5. Your factual account of the relevant events
6. Your legal or factual reasons for disagreeing with the CRA's position
7. Supporting documents — receipts, invoices, contracts, bank records, or anything else that substantiates your position

Think of the objection as telling your side of the story in an organized, factual way. The appeals officer assigned to your file will review both the objection and the auditor's file.

Quality matters

A vague objection that simply says "I disagree with the reassessment" gives the appeals officer almost nothing to work with. A well-structured objection that identifies specific errors, provides clear documentation, and explains the applicable legal principles is far more likely to succeed — or at least to narrow the dispute before it reaches court.

How to Submit Your Notice of Objection

You can file by:

• Online: Through your CRA My Account (for individuals) or My Business Account (for businesses) — the objection can be submitted electronically
• Mail: Send to the Chief of Appeals at the appropriate CRA Tax Services Office serving your area (confirm the address from the CRA website)
• Keep proof: Always retain a copy of what you filed and obtain confirmation of receipt

What Happens After You File

Once the CRA receives your Notice of Objection:

1. Acknowledgment: CRA will send you a confirmation that the objection has been received.
2. Assignment to an appeals officer: A different CRA officer (not your auditor) reviews the file.
3. Communication: The appeals officer may contact you or your representative for additional information or to discuss settlement.
4. Decision: The appeals officer can:

• Allow the objection (your position wins)
• Allow it in part (a compromise)
• Dismiss it (the reassessment stands)

This process can take months — sometimes considerably longer, especially for complex business disputes or when CRA's appeals inventory is backed up. Interest continues to run on any unpaid tax during this period.

If the objection is dismissed and you still believe you are right, you have the right to appeal to the Tax Court of Canada. The deadline to appeal to the Tax Court runs from the date of CRA's decision on your objection (as of writing — verify immediately with a tax professional).

Should You Pay the Balance While Your Objection Is Pending?

Paying stops interest from accruing on that amount. You can always get a refund later if you win. If you can't pay, you can request a payment arrangement, or ask about a collections hold while the objection is active. The CRA generally refrains from active collection of disputed amounts during the objection process, but this is not guaranteed and varies by circumstance.

Frequently asked questions