Appealing to the Tax Court of Canada: What Ontario Taxpayers Need to Know

When the CRA dismisses your Notice of Objection and you still believe the reassessment is wrong, your next recourse is the Tax Court of Canada. For many Ontario taxpayers, this feels like intimidating territory — a federal court, legal procedure, judges. But the Tax Court was specifically designed to be accessible to taxpayers, including those without lawyers, and it has a simplified procedure for smaller disputes.

This article explains how appealing to the Tax Court of Canada works, what the two procedures are, the strict deadlines involved, and what to expect if your case goes to hearing.

What Is the Tax Court of Canada?

The Tax Court of Canada is a federal court with exclusive jurisdiction over disputes between taxpayers and the CRA about federal income tax, GST/HST, employment insurance premiums, and Canada Pension Plan contributions. It is not the same as Ontario's provincial courts — it is a federal institution with offices in major cities across Canada, including Toronto.

The Tax Court operates independently of the CRA. Judges are not CRA employees. The court's job is to determine the correct amount of tax owed under the law — not to rubber-stamp the CRA's position.

When Can You Appeal to the Tax Court?

You can only appeal to the Tax Court after the CRA has responded to your Notice of Objection (see our article on filing a Notice of Objection). You cannot skip directly to the court without first going through the objection process, except in narrow circumstances where the CRA has not acted on an objection within 90 days of it being filed.

Once the CRA issues its Notice of Confirmation (upholding the reassessment) or a new Notice of Reassessment after the objection, your appeal clock starts.

Deadline: As of writing, the deadline to file a Tax Court appeal is 90 days from the date of the confirmation or reassessment. Verify this immediately with a tax professional. Missing this deadline ends your right to appeal — there is a mechanism to apply for an extension, but it is not guaranteed.

Two Procedures: Informal vs. General

The Tax Court of Canada has two ways to hear tax appeals:

Informal Procedure

• Designed for disputes involving smaller amounts of tax (as of writing — verify current thresholds with the Tax Court or a tax professional)
• Less formal rules of evidence and procedure — you can represent yourself more easily
• Hearings tend to be shorter and more conversational
• The court's decision binds only the parties (not future cases)
• No automatic right of appeal from an informal procedure judgment (though judicial review may be available)

General Procedure

• Applies to disputes involving larger amounts or cases where the taxpayer has elected to use general procedure for strategic reasons
• Full litigation rules apply: discoveries, motions, formal pleadings
• Expert witnesses are common for complex valuation or transfer pricing disputes
• The court's decisions create precedent
• Appeals from General Procedure judgments go to the Federal Court of Appeal, and further to the Supreme Court of Canada

For most Ontario individuals and small business owners, the informal procedure handles the dispute. But the thresholds matter — confirm which applies to your situation.

How to File a Tax Court Appeal

To start an appeal, you file a Notice of Appeal with the Tax Court. It must include:

• Your name, address, and tax identification number
• The years or periods under appeal
• The issues in dispute
• The relief you are seeking (i.e., what you want the court to change)
• A summary of the material facts and legal grounds

For informal procedure appeals, the forms are simpler. The Tax Court's own website has forms and instructions available. Even so, a well-drafted Notice of Appeal sets the tone for the entire proceeding — a vague or disorganized filing puts you at a disadvantage.

What Happens After Filing

Crown reply

The Department of Justice (not CRA) responds to your appeal on behalf of the Crown. A Crown counsel lawyer will be assigned to oppose your appeal. This is worth noting: you are now in formal legal proceedings against government lawyers. Having your own legal counsel becomes significantly more important at this stage.

Discovery

In General Procedure matters, both parties exchange relevant documents and may examine witnesses under oath (examinations for discovery) before the hearing. This is the litigation stage where the strength of each side's evidence becomes clear, and where many cases settle.

The hearing

Tax Court hearings are conducted before a judge (no jury). Each side presents its evidence and arguments. The judge may ask questions. After the hearing, the judge issues a written judgment explaining the decision and the legal reasoning.

Settlement

Many Tax Court appeals settle before ever reaching a hearing. The Crown counsel assigned to your file has authority to negotiate, and settlements can happen at any stage — immediately after filing, during discovery, or even on the courthouse steps. A well-documented case with strong legal arguments puts you in a better negotiating position.

What Can the Tax Court Order?

The Tax Court can:

• Dismiss your appeal (CRA's reassessment stands)
• Allow your appeal and vacate the reassessment (you win entirely)
• Allow your appeal in part and reduce the reassessment (partial win)
• Refer the matter back to the Minister for reassessment on specific grounds

The court cannot award you costs in the informal procedure. In the general procedure, cost awards are possible.

Frequently asked questions