Notice of Assessment (NOA): What It Means for Your Taxes

Whether it relates to your personal tax return or your corporation's filing, a notice of assessment is often opened too quickly—or set aside without being read carefully. Yet as soon as you submit a return, the Canada Revenue Agency (CRA) or Revenu Québec issues this official income tax notice of assessment, the document that summarizes their tax decision: the amount you owe or will receive, the credits applied, and any adjustments made.

For business owners, this document can be especially important. It helps confirm your tax position, explain differences between your calculations and those made by the tax authorities, and support a financing request if needed. It is also a key part of responsible business tax accounting, since it ensures that what you filed aligns with what the government assessed.

At T2inc.ca, we assist hundreds of Canadian businesses each year with their corporate tax filings and overall corporate tax compliance. This guide explains what a notice of assessment is, where to find it, how to read it, and what to do if something seems incorrect—both for individuals and for incorporated businesses.

What is a Notice of Assessment?

A notice of assessment—sometimes referred to as a tax assessment notice—is an official document issued by the CRA or Revenu Québec after they process your tax return. It confirms the tax assessment performed and specifies:

• the amount of tax owed or refunded,
• the credits accepted or denied,
• the instalments applied, and
• any adjustments made to your return.

This document summarizes the final tax decision for your personal return (T1 / TP1) or your corporate return (T2 / CO-17). It validates the information submitted, confirms your balance, and serves as proof for audits, administrative requests, or a formal objection. It is also an essential reference for your tax return evaluation, especially if a reassessment occurs.

What Is a Notice of Assessment Used For?

In short, a notice of assessment allows you to:

• Verify the actual tax calculated by the CRA or Revenu Québec.
• See which credits and deductions were applied.
• Understand adjustments made to your tax information.
• Keep an essential tax document for financing, audits, or administrative requests.
• Use it as a basis to correct your tax return or file an objection.
• Ensure proper compliance with both federal and provincial tax requirements.

How to Receive Your Notice of Assessment?

You can access your notice of assessment online or receive it by mail, depending on the correspondence preferences set with the CRA or Revenu Québec. To receive it more quickly—without mail delays—activating electronic correspondence is strongly recommended. Otherwise, postal delivery may take longer and complicate the way you store your tax documents, especially if you receive multiple notices over the years. Typical processing times range from 2 to 8 weeks depending on the return type and whether additional review is required.

At the Federal Level (CRA)

Your notice of assessment is accessible through the CRA's secure online platform, including:

• My Business Account (for corporations);
• My Account (for individuals);
• Online Mail, if electronic correspondence is enabled.

If the notice does not appear after normal processing times, check whether your return is still being reviewed, and contact the CRA if needed. More details are available on the CRA's official page about notices of assessment (NOA / NOR).

In Quebec (Revenu Québec)

In Quebec, your notice is available through:

• My Account for Businesses;
• My Account for Individuals.

If the document is lost, Revenu Québec allows you to request a copy directly from your account or by phone. Their official page provides full details on the Quebec notice of assessment and how the income tax assessment process works at the provincial level.

Where to Find Your Notice of Assessment Number?

Your notice of assessment number is a unique identifier that allows the CRA or Revenu Québec to quickly locate your file. It is required for several administrative procedures, such as submitting an objection, confirming your identity, or accessing certain online services.

• CRA (Federal): located in the top right corner of T1 and T2 notices.
• Revenu Québec (Provincial): found in the top right corner of TP1 and CO-17 notices, often beginning with M or Q.

Keep this number in a secure place. It may be required during audits, inquiries, or the tax assessment review that occurs when filing a notice of objection.

How to Read Your Notice of Assessment?

A notice of assessment may appear complex at first glance—especially if it's your first tax assessment notice—but it follows a consistent structure. Each section helps confirm whether the tax assessment aligns with the information in your return and the expected tax filing process.

1. Identification Number

Located at the top of the document, this is the unique identifier attached to your assessment. It allows tax authorities to locate your file quickly and may be required when submitting questions or objections.

2. Amount Owing or Refunded

This section shows whether:

• you owe an amount,
• you will receive a refund, or
• your balance is zero.

It also indicates any interest or penalties applied. For corporations, unpaid balances generate daily interest from the due date—another reason to stay on top of your corporate income tax return obligations.

3. Refund (If Applicable)

If you overpaid your taxes, the notice specifies:

• the refund amount,
• sometimes the expected deposit date, and
• whether part of the refund was applied to a previous balance.

For corporations, refunds may result from a tax credit, instalment overpayment, or a favourable adjustment—helping improve liquidity and managing business records through accurate reconciliation.

4. Tax Credits and Adjustments

This section presents the assessed tax credits and deductions as well as the corrections made by the tax authorities.

• Personal notice (T1 / TP1): includes applied personal credits (e.g., GST/HST credit, medical expenses, tuition) and any credits denied with explanations.
• Corporate notice (T2 / CO-17): includes accepted or denied corporate tax credits (e.g., SR&ED, investment credits) and adjustments to schedules.

You may also see carryforward amounts, such as losses or unused credits, which may affect future tax years.

5. Explanations for Adjustments

If your return was corrected, the notice includes a summary of the changes and, in some cases, reference codes. Common reasons include:

• added or corrected income,
• a credit deemed ineligible,
• instalments applied differently,
• a data-entry correction, or
• missing supporting documents.

If something looks unusual, compare your notice with your return and slips before contacting the tax authorities or consulting a professional.

What If You Disagree With Your Notice of Assessment?

Yes, it is entirely possible to file an objection when there is an error on your tax assessment notice. Before taking this formal step, however, it is essential to check where the discrepancy comes from and determine whether the correction should be made by you or by the tax authorities. Here are the steps to follow to analyze the situation and choose the right course of action.

If you disagree with your assessment, here are the steps to follow:

1. Review your return and your tax slips.
2. Identify the adjustment that seems incorrect.
3. Correct your return online, if the error comes from you.
4. File a formal objection if the issue comes from the CRA or Revenu Québec's assessment.
5. Respect the deadlines, typically 90 days.

T2inc.ca Can Help You Navigate Your Corporate Tax Obligations

A notice of assessment is more than a simple document—it confirms how your return was processed and whether your personal or corporate tax situation needs adjustments. Reading it carefully, storing it properly, and comparing it with your return helps avoid misunderstandings and simplifies future administrative steps.

If something seems inconsistent, take a moment to review the notice in detail. Most answers are already included. And if you need clarification, don't hesitate to contact the CRA or Revenu Québec—or consult a tax professional.

At T2inc.ca, we know that corporate tax compliance can quickly become complex. If you need help preparing your T2 corporate tax return or CO-17 Quebec corporate return, our team can guide you through your obligations and help you manage your business taxes with clarity and confidence.

FAQ – Everything You Need to Know About the Notice of Assessment in Canada

💬 What is a pre-assessment notice?

It is the initial tax decision issued by the CRA or Revenu Québec after reviewing your return. It shows the tax calculated, credits accepted or denied, instalments applied, and the final balance.

💬 What is a notice of reassessment?

A notice of reassessment is the revised version of your original notice. It is issued when the CRA or Revenu Québec adds income, adjusts credits, or receives new information that affects your tax calculation.

💬 Does a notice of assessment mean you owe money?

Not necessarily. Your notice may show an amount owing, a refund, or a zero balance. It depends entirely on the tax assessment performed by the authorities.

💬 How do I object to a notice of assessment?

You must file a formal objection within 90 days of the date shown on the notice. The CRA or Revenu Québec will require an explanation and supporting documents.