Receiving a tax assessment from the Canada Revenue Agency that you believe is incorrect can feel overwhelming. Whether the CRA has denied a deduction, reassessed your income, or disputed a credit you claimed, you have legal rights to challenge their decision. The objection and appeal process exists precisely for this purpose — and understanding how it works can make the difference between paying a bill you do not owe and recovering money that is rightfully yours.
What Is a CRA Notice of Objection?
A Notice of Objection is a formal written dispute filed with the CRA challenging a tax assessment or reassessment. When the CRA issues a Notice of Assessment (NOA) or Notice of Reassessment (NOR), you have the right to object if you believe the figures are wrong, that the CRA has misapplied the law, or that relevant facts were not considered.
The objection process is administered under the Income Tax Act (for personal and corporate income tax), the Excise Tax Act (for GST/HST disputes), or the Employment Insurance Act and Canada Pension Plan legislation for source deduction matters. Each has its own rules, but the general principles are the same.
The 90-Day Deadline: Do Not Miss It
This is the single most important number to remember: 90 days from the date printed on your Notice of Assessment or Reassessment to file your objection. Missing this deadline can forfeit your right to dispute the assessment entirely.
There is one important exception. For individuals and testamentary trusts objecting to income tax assessments, you have a longer window — the later of:
- 90 days from the date of the notice, or
- One year from the filing deadline for the return in question
For example, if your 2024 T1 return was due 30 April 2025 and the CRA reassesses you in August 2025, you would have until 30 April 2026 (one year from the due date) rather than just 90 days from the reassessment date.
Corporations and trusts other than testamentary trusts have only the strict 90-day window. If you have missed the deadline, you can apply for an extension — but the CRA will only grant one if you demonstrate you had a bona fide intention to object within the original 90 days and that it is just and equitable to allow the extension. Extensions are not guaranteed.
Common Grounds for Disputing a CRA Assessment
Not every disagreement with the CRA is a winning objection, but there are well-established grounds on which taxpayers successfully challenge assessments:
- Factual errors: The CRA used incorrect income figures, double-counted income, or missed deductions and credits that were properly claimed.
- Legal interpretation: The CRA has applied the law incorrectly or more broadly than Parliament intended.
- Missing documentation: An auditor disallowed expenses because supporting receipts were not provided during the audit — you now have the documentation.
- Valuation disputes: The CRA disagrees on the fair market value of property, shares, or a business interest.
- Shareholder benefit or attribution issues: The CRA has attributed income or benefits to you that you dispute.
- Statute-barred reassessments: The CRA has reassessed outside the normal three-year reassessment period without establishing misrepresentation or fraud.
How to File a Notice of Objection
The CRA provides Form T400A for income tax objections, though a letter that clearly identifies the assessment being disputed and the reasons for objection is also acceptable. For GST/HST disputes, there is no prescribed form — a written letter will suffice.
Your objection must include:
- Your name, address, and social insurance number (or business number)
- The date and number of the assessment or reassessment you are disputing
- The tax year(s) in question
- A clear statement of the facts you rely on
- The reasons why the assessment is incorrect
- The amount of tax you believe is properly owing
Submit your objection to the Chief of Appeals at your tax services office — not to the auditor who issued the assessment. You can file by mail, by fax, or through My Account on the CRA website. Keep a copy and obtain proof of delivery.
What Happens After You File
Once your objection is received, the CRA assigns it to an Appeals Officer — an independent reviewer who was not involved in the original assessment. The officer will contact you (or your representative) to discuss the issues, request additional information, and attempt to resolve the dispute at the administrative level.
The CRA may:
- Allow the objection in full: The assessment is vacated or varied in your favour.
- Allow the objection in part: Some issues are resolved in your favour, others are not.
- Disallow the objection: The CRA confirms its original assessment.
There is no statutory deadline by which the CRA must resolve an objection, and wait times have historically ranged from several months to several years depending on complexity. During this time, collections action on the disputed amount is generally held in abeyance, though interest continues to accrue on any amount ultimately found to be owing.
A Practical Example
Consider a Calgary-based consultant who received a 2024 Notice of Reassessment in March 2025. The CRA disallowed $18,400 in home-office expenses, resulting in additional tax of approximately $7,360 plus interest. The reassessment date was 15 March 2025, giving her until 13 June 2025 to file her objection (90 days).
She gathered her lease agreement, utility bills, a floor-plan showing her dedicated workspace represented 22% of her total home area, and internet invoices. Her objection letter cited subsection 18(12) of the Income Tax Act and attached the documentation. The Appeals Officer, reviewing the case fresh, accepted the documentation and allowed 20% of the home-office expenses (a minor reduction). Her reassessment was varied, her additional tax liability dropped from $7,360 to roughly $920, and the difference was refunded. The whole process took eight months.
This example illustrates why filing is nearly always worth doing — even a partial win can meaningfully reduce your tax bill.
Escalating to the Tax Court of Canada
If the CRA disallows your objection, or if 90 days pass after you file your objection without a decision, you have the right to appeal to the Tax Court of Canada. The deadline to file a Tax Court appeal is 90 days from the date the CRA confirms or varies the assessment (or from the date the 90-day wait period expires).
The Tax Court offers two procedures:
- Informal Procedure: Available where the amount of federal tax and penalties in dispute is $25,000 or less (or $50,000 for loss determinations). The process is streamlined, less formal, and you can represent yourself. Decisions are binding but cannot be appealed further.
- General Procedure: For larger amounts or complex issues. Full rules of evidence apply, and you would typically retain tax counsel. Decisions can be appealed to the Federal Court of Appeal and ultimately the Supreme Court of Canada.
The Tax Court is an independent court — judges are not CRA employees — and it hears the dispute entirely fresh on the merits. Many taxpayers who were unsuccessful at the objection stage have prevailed in Tax Court.
Should You Hire a Representative?
You can navigate an objection yourself, and for straightforward factual disputes (missing receipts, a T4 that was reported twice), many taxpayers do so successfully. For complex issues — valuation disputes, shareholder benefit assessments, transfer pricing, or any matter involving significant amounts — professional representation typically pays for itself.
A qualified tax accountant or tax lawyer can assess whether your position has merit before you file, structure your objection effectively, negotiate with the Appeals Officer, and decide whether escalating to Tax Court makes strategic sense. At Swift Accounting Ltd. in Calgary, we regularly assist clients through the CRA objection process, helping them present the strongest possible case and avoid procedural missteps that could jeopardize an otherwise valid dispute.
Frequently Asked Questions
How long does the CRA objection process take in 2025?
There is no legislated deadline for the CRA to resolve an objection. Simple cases involving clear factual errors may be resolved in three to six months, while complex disputes — particularly those involving business valuations or significant amounts — can take two to three years or longer. The CRA's objection inventory has historically been backlogged, though their Objections and Appeals branch has been working to reduce wait times. If more than 90 days have passed without a decision, you have the right to bypass the objection process and go directly to the Tax Court of Canada.
Do I have to pay the disputed tax while my objection is pending?
For income tax disputes, the CRA will generally not pursue collections on the amount under objection while it is pending, though this is not an absolute rule and they retain the right to collect. Interest on any amount ultimately confirmed continues to accrue throughout the objection period, which is one reason resolving disputes quickly is in your financial interest. For GST/HST disputes, the CRA can collect amounts owing even during an objection, though you can apply for a collections waiver.
What if I missed the 90-day objection deadline?
You can apply to the CRA for an extension of time to file your objection. This application must itself be made within one year of the original 90-day deadline (so within approximately 15 months of the assessment date). You must demonstrate that you had a genuine intention to object within the 90-day period, that it would be just and equitable to grant the extension, and that the application was made as soon as circumstances permitted. Extensions are not automatic — the CRA exercises discretion, and if it refuses, you can apply to the Tax Court of Canada for an order granting the extension.
Can I object to a CRA audit result even if I agreed to the audit findings at the time?
Yes, in most cases. Signing a waiver of objection rights during an audit is different from simply accepting audit-proposed adjustments verbally or in writing. If you did not sign a formal waiver (Form T2029 for income tax), you retain your right to object once the formal Notice of Reassessment is issued. However, any agreements or representations you made during the audit may be relevant to the merits of your objection and could affect the Appeals Officer's assessment of your position. This is one reason it is advisable to involve a tax professional before agreeing to anything during an audit — not just after.
Take Action Before the Deadline
A CRA reassessment is not the final word. The objection and appeal process gives every Canadian taxpayer a meaningful right to challenge assessments that are factually wrong or legally unsound — but that right expires if you do not act within the prescribed deadlines. If you have received a Notice of Assessment or Reassessment that you believe is incorrect, the most important step you can take is to get professional advice promptly, well before the 90-day clock runs out. The team at Swift Accounting Ltd. is available to review your assessment, advise whether an objection is warranted, and represent you through the process. Contact us today to discuss your situation and protect your rights.