CRA Compliance & Reporting

Notice of Objection CRA: How to Dispute a Reassessment

By August 10, 2026 No Comments
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This article is for informational purposes only and does not constitute tax or financial advice. Consult a qualified accounting professional before making any tax or financial decisions.

Quick Answer

A notice of objection is the formal written dispute you file with the CRA when you disagree with a Notice of Assessment or Reassessment. You generally have 90 days from the date printed on the notice to file it, either through CRA My Account, CRA My Business Account, or on paper using Form T400A.

The objection goes to the CRA Appeals Branch, which reviews your position independently of the auditor who issued the reassessment. For most individual taxpayers, filing the objection typically pauses collection of the disputed amount while the file is under review.

If the CRA denies your objection, the next step is an appeal to the Tax Court of Canada, which has its own filing rules and deadlines.

The Envelope on the Kitchen Table

The envelope sits on the kitchen table. Inside, a letter from the Canada Revenue Agency says you owe more tax than you thought. The number is bigger than the return you filed. The tone is calm. The date at the top of the page has quietly started a 90-day countdown you never asked for.

Take a breath. Most CRA letters are the opening move in a negotiation, not a verdict. The reassessment on the page is the CRA’s position, and Canadian tax law gives you a formal way to push back. It is called a notice of objection, and filing one on time is the single most important step anyone in your situation can take.

This guide walks through the whole process in plain English. Before you do anything else, understand your CRA compliance obligations and read the date at the top of the letter. That date is your clock.

90 daysObjection filing window
0%Typically collectible during review
3Possible outcomes
90 daysTax Court appeal window

Pick Your Path in 60 Seconds

The right form and process depend on your taxpayer type. Individual filers and sole proprietors use CRA My Account or Form T400A. Incorporated professionals and SMEs with a T2 reassessment use CRA My Business Account or Form T400A. GST/HST assessments use Form GST159 and follow parallel but distinct rules under the Excise Tax Act.
Individual T1 filer
Log into CRA My Account and use Register a Formal Dispute, or mail Form T400A. Clock runs from the date on the reassessment.
Sole proprietor
Business-income adjustments still file on the personal T1 side. Same form, same channel, same clock.
Incorporated / SME (T2)
Use CRA My Business Account or Form T400A. The corporation, not the shareholder, is the objecting party. See filing through CRA My Business Account.
GST/HST assessment
Form is GST159; deadline still generally 90 days. Excise Tax Act rules govern instead of the Income Tax Act.

If your 90 days is already gone, jump ahead to the Common Mistakes section for the late-filing safety valve.

What Kind of Notice Are You Actually Holding

The CRA issues three related documents that readers confuse. A Notice of Assessment is the first result after you file a return. A Notice of Reassessment is a later CRA change to those numbers. A Notice of Confirmation, Variation, or Determination is what you receive after you object. Only a reassessment generally starts a fresh objection clock; a plain assessment usually does not.

Read the top of the letter. If it says Notice of Reassessment, you have a new 90-day window. If it says Notice of Assessment, the objection right is still open, but the clock started the day the notice was issued.

Document What triggers it What it starts Your window Form
Notice of AssessmentYou filed a returnOriginal tax liability90 days from date on noticeT400A
Notice of ReassessmentCRA changed the numbers laterFresh 90-day objection right90 days from date on noticeT400A
Notice of Confirmation or VariationYou objected and CRA decidedTax Court appeal window90 days from decision dateTax Court Notice of Appeal

The distinction matters because your rights and next steps depend on which document is in front of you.

The Step-by-Step Roadmap From Letter to Decision

The process runs in ten steps: read the notice and identify the date, mark the 90-day deadline, gather your evidence, choose your filing channel, write the objection, file with proof, wait for Appeals Branch assignment, respond to information requests, receive the decision, and, if you still disagree, note the separate Tax Court deadline.
  1. 1
    Read the notice Identify the tax year, the specific adjustments, and the date printed at the top. That date is the anchor for every deadline that follows.
  2. 2
    Confirm the 90-day deadline Put it in two calendars. Not one. Two.
  3. 3
    Gather your evidence Pull the return, the working papers, supporting documents, and the CRA correspondence file. Know what to have ready before you respond.
  4. 4
    Choose your filing channel CRA My Account or CRA My Business Account is fastest and gives an immediate confirmation. Paper Form T400A works too, but Canada Post transit counts against your 90 days.
  5. 5
    Write the objection Identify each disputed item line by line, state your position, cite the facts and the section of the Income Tax Act or Excise Tax Act that supports you, and specify the relief you want.
  6. 6
    File and keep proof Save the CRA confirmation email or tracked-mail receipt.
  7. 7
    Wait for Appeals Branch assignment Reviews typically take several months and can run longer, depending on complexity and backlog.
  8. 8
    Respond quickly to any Appeals Officer request Missing a reply window can weaken a strong file.
  9. 9
    Receive the decision It will be Allowed, Varied, or Confirmed.
  10. 10
    Escalate if needed If Confirmed and you still disagree, appeal to the Tax Court of Canada. That is a separate 90-day window running from the decision date, not the original notice.
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The Objection Clock — What Happens and When

Two fixed 90-day windows anchor the process. The Appeals Branch review sits between them, with variable timing.

Sources: Income Tax Act s.165 and s.166.1 (Justice Laws Canada) · CRA — File an objection (canada.ca). Appeals Branch review shown as an indicative window; individual timelines vary with complexity and backlog. ClearWealth Accounting Advisors · clearwealth.tax · For informational purposes only.

What Goes Inside a Strong Written Objection

A strong written objection has five moving parts. State the facts as you see them, in plain language. Identify each reassessment item you dispute, one by one. Give the legal or factual basis for each disputed item, whether that is the specific figures, the specific section of the Income Tax Act, or the specific third-party document that supports you. Say clearly what relief you want, whether that is the corrected tax owed, the deletion of a penalty, or the reinstatement of a deduction. List the supporting documents you have attached.

The Appeals Officer who reads your objection is not the auditor who issued the reassessment. They see the file fresh. That is why a clear, well-organized submission is meaningfully easier for them to allow than a stack of receipts and a paragraph of frustration. The clearer you make the path to your position, the more likely they are to walk down it.

Skip the tone of grievance. Argue facts, argue law, request the outcome.

Collections, Interest, and Cash Flow While You Wait

For most individuals and small Canadian-controlled private corporations, filing an objection generally pauses CRA collection of the disputed amount until the Appeals Branch decides. Interest, however, keeps accruing on the disputed balance during the wait. Large corporations must pay 50 percent of the disputed amount pending decision. Jeopardy assessments are the narrow exception where the CRA can bypass the collections pause.

The practical consequence is a cash-flow decision. If your position is strong and you expect to win, holding the disputed cash preserves working capital, and any interest that accrued is refunded with the balance. If your position is weak and you expect to lose, paying early caps the interest cost so the bill does not grow while you wait.

Large-corporation status has a specific definition in the Income Tax Act. Most SMEs do not meet it. If you are not sure, ask your accountant before you decide.

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How Much of a Disputed Balance the CRA Can Collect While You Object

Collections rules by taxpayer type. Individuals and small corporations typically get a full stay; large corporations do not.

Sources: Income Tax Act s.225.1 (collection restrictions) and s.225.2 (jeopardy assessments) — Justice Laws Canada. Large corporation defined per ITA s.225.1(8). Interest continues to accrue on the disputed balance during any stay. ClearWealth Accounting Advisors · clearwealth.tax · For informational purposes only.

Common Mistakes That Sink Otherwise Winnable Objections

The mistakes below appear in almost every file where a good position lost anyway. Read common CRA audit mistakes alongside these. The two lists overlap.

  • →Treating the 90 days as elastic. It is not. The deadline runs from the date on the notice, and CRA extensions are discretionary, not automatic.
  • →Filing without identifying disputed items line by line. Appeals Officers need to know what you are challenging and why. Vague objections get vague answers.
  • →Attaching documents without explaining what they prove. A stack of receipts is not evidence until you tell the reader which line of the reassessment each receipt contradicts.
  • →Arguing tone or fairness instead of facts and law. The Appeals Branch decides on facts and the Income Tax Act, not on how the auditor made you feel.
  • →Missing the Appeals Officer’s reply window. That single skipped email can turn a winnable file into a Confirmed decision.
  • →Forgetting the separate 90-day Tax Court clock after a Confirmation. Two different clocks, two different dates.
  • →Paying the balance and assuming the file is closed. Payment is not withdrawal. If your objection is still alive when the CRA agrees you were right, the money comes back.
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What the CRA Appeals Branch Does With Objections

Indicative outcome distribution. Objections are decided one of three ways: Allowed in full, Varied in part, or Confirmed.

Percentages shown are indicative placeholders reflecting the general shape of published CRA Appeals data. Verify against the most recent CRA Departmental Results Report (canada.ca/revenue-agency) before publish. Actual proportions vary by year and taxpayer segment. ClearWealth Accounting Advisors · clearwealth.tax · For informational purposes only.

Accountant, Tax Lawyer, or Both

An accountant handles most objections. They own the return, the working papers, and the numbers under dispute. They can talk directly with the Appeals Officer, provide the supporting documents, and often resolve the file before litigation is on the table. For most SME and T2 objections, an accountant-led response is the right first move, and the more affordable one.

A tax lawyer earns their fee when the dispute turns on interpretation of the Income Tax Act, when the amounts are large enough to justify litigation, or when the case is likely to end up in the Tax Court of Canada. Legal counsel is not the default step for a modest reassessment on missed vehicle expenses. It is the right step for a serious GAAR argument.

Sequence matters. A well-run accountant-led objection often closes the file before a lawyer is needed. Explore ClearWealth tax services if you want a second pair of eyes on your file.

Frequently Asked Questions

How long do I have to file a notice of objection with the CRA?

Generally 90 days from the date printed on the Notice of Assessment or Reassessment, counted in calendar days. If the 90th day falls on a weekend or federal holiday, the deadline typically shifts to the next business day.

Do I have to pay the CRA while my objection is being reviewed?

For most individuals and small corporations, no. Collection of the disputed amount is generally paused under Income Tax Act section 225.1. Interest keeps accruing on that balance. Large corporations must pay 50 percent of the disputed amount pending decision.

What happens if I miss the 90-day objection deadline?

You may still apply for an extension of time under Income Tax Act section 166.1, up to one year past the original deadline. The application must be in writing, must explain the delay, and is not automatic. File the extension request and the objection together.

Do I need a lawyer to file a notice of objection?

Not usually. Most objections are handled by the taxpayer or their accountant. A tax lawyer is worth the cost when the dispute turns on interpretation of the Income Tax Act, when the amount is large, or when Tax Court is a realistic next step.

What if the CRA denies my notice of objection?

You can appeal to the Tax Court of Canada within 90 days of the CRA decision. The Tax Court has two procedures: informal, for smaller amounts, and general, for larger ones. Further appeals to the Federal Court of Appeal may be available.

Can I object to a GST/HST assessment the same way as income tax?

The process is parallel but not identical. GST/HST objections use Form GST159 and are governed by the Excise Tax Act rather than the Income Tax Act. The 90-day clock generally still applies. If your file mixes both streams, each needs its own objection.

Want a Second Set of Eyes on Your Reassessment?

If the amounts are meaningful, the file is complex, or the 90-day clock is close, book a strategy call with our team. We work through the reassessment, draft the objection, and manage the Appeals Branch conversation.

Book a Consultation
This article is for informational purposes only and does not constitute tax, legal, or accounting advice. Consult a qualified professional for guidance specific to your situation.

Sources & References