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Missed the 90-Day Tax Court of Canada Appeal Deadline? Next Steps

Missed the 90-day deadline to appeal to the Tax Court of Canada? See how to apply for an extension, the one-year limit and what the Court requires.

Tax5 min readTSLBy the Treadstone Law Team · CanadaUpdated November 1, 2026
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Key takeaways
  • The Court must receive your notice of appeal within 90 days of the date on the notice of confirmation or reassessment.
  • An extension application must be made within one year after the 90-day period expires.
  • You must show you could not act or had a bona fide intention to appeal, that it is just and equitable, that you applied promptly, and that there are reasonable grounds.

If you have missed the deadline to appeal to the Tax Court of Canada, the case is not necessarily over. The Income Tax Act allows you to ask the Court for more time, but only within strict limits and only if you can show specific things.

This article walks through the 90-day rule, the extension application and what the Court requires. Because the one-year limit is firm, speak with a lawyer quickly.

This article covers Canadian federal tax law, which applies in every province.

The 90-day rule and its exceptions

After you serve a notice of objection, you may appeal to the Tax Court once the Minister has confirmed the assessment or reassessed. The deadline is 90 days from the day the notice was sent to you saying the Minister confirmed or reassessed. The CRA says the Court must receive the notice of appeal within 90 days of the date on that notice.

There are exceptions. If the Minister has not notified you of a decision, you may appeal once 90 days have passed after service of the notice of objection, and for GST/HST objections the wait is 180 days. For ecological gifts, an appeal of the Minister of the Environment's decision on fair market value must be made within 90 days after that Minister issues the certificate.

The objection stage comes first. A notice of objection must be in writing and set out the reasons and all relevant facts. On receiving it, the Minister must, with all due dispatch, reconsider the assessment and vacate, confirm or vary it or reassess, then notify you in writing. A special rule applies where the Minister assesses to reflect certain matters already determined: the objection must be made within 90 days, and the objection and appeal are limited to reasons that cannot reasonably be regarded as already dealt with.

Applying for an extension

If the deadline has passed, you may apply to the Tax Court for an order extending the time to appeal, and the Court may impose terms it considers just. The application sets out the reasons for the delay and is filed with three copies of the application and three copies of the notice of appeal. The Court sends a copy to the office of the Deputy Attorney General of Canada.

Which procedure your appeal follows depends on the amounts involved. The informal procedure applies where the aggregate of the amounts in issue is $25,000 or less, or the loss in issue is $50,000 or less, and you elect it. It also applies where the only subject-matter is interest assessed under the Income Tax Act, but in an interest-only informal appeal the Attorney General may apply to move the case to the general procedure, and the Court must grant it if the interest in issue exceeds $25,000, not counting interest that accrues after the notice of assessment. If the amounts exceed those limits, the Court orders the general procedure unless you elect to limit the appeal to those amounts.

The one-year limit

No extension order can be made unless the application is made within one year after the 90-day appeal period expires. The CRA describes this as one year and 90 days from the confirmation or reassessment. If you are close to that date, treat it as urgent.

What the Court requires you to show

RequirementIn plain words
Reason for delayWithin the 90 days you were unable to act or instruct someone to act, or you had a bona fide (genuine) intention to appeal
FairnessIt is just and equitable to grant the application
PromptnessYou applied as soon as circumstances permitted
MeritThere are reasonable grounds for the appeal

Meeting all of these is required, not just one. Evidence helps: letters, emails, medical records or notes showing you meant to appeal and why you could not.

Related situations and next steps

A late notice of objection is handled differently. You first apply to the Minister (Chief of Appeals) under s. 166.1, within one year after the objection deadline. For individuals other than trusts, the objection deadline is the later of one year after the filing-due date or 90 days after the notice of assessment was sent.

Also, you cannot appeal an issue on which you waived in writing the right to object or appeal. Relief from penalties or interest under s. 220(3.1) is a CRA administrative decision, not a Tax Court appeal. If a relief request is refused, a taxpayer who thinks the CRA was not fair and reasonable can apply to the Federal Court for judicial review within 30 calendar days of receiving the decision.

Frequently asked questions

Can I still appeal if I am a few days late?

You may apply to the Tax Court for an order extending the time to appeal. The Court must be satisfied on each requirement, including that you applied as soon as circumstances permitted and that there are reasonable grounds for the appeal.

How long do I have to ask for an extension?

The application must be made within one year after the 90-day appeal period expires. No extension order can be made after that.

What do I file with the extension application?

The application sets out the reasons for the delay and is filed with three copies of the application and three copies of the notice of appeal.

What if I missed the deadline for a notice of objection instead?

That is dealt with differently. You first apply to the Minister (Chief of Appeals) under s. 166.1 within one year after the objection deadline.

Sources

Links go to official government, court and regulator pages. The law changes — confirm you are reading the current version.

This article is general information, not legal advice. Reading it does not create a lawyer-client relationship. Canadian laws, tax rates, and government programs change, and how the law applies depends on your specific facts. For advice about your situation, speak with a tax lawyer or accountant. Reach us at 1-844-900-1070 or send our Team a message.

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