CRA Reassessment or Review Letter: What It Means and How to Respond

Opening a letter from the CRA that says your return has been reassessed or selected for review is unsettling. But it does not necessarily mean you did something wrong, and it does not mean you are being audited. In most cases, it is a routine process with a clear path to resolution.

This guide explains the difference between a review and a reassessment, why the CRA might contact you, how to respond effectively, and what to do if you disagree with the outcome.

Review vs. Reassessment: What Is the Difference?

These terms sound similar but they mean different things.

Pre-Assessment Review

A pre-assessment review happens before the CRA processes your return. The CRA holds your return and asks you to verify or provide documentation for specific claims. Common triggers include:

• Large charitable donation claims
• First-time business expense claims
• Claims that differ significantly from prior years

You receive a letter asking for supporting documents. Once you provide them, the CRA finishes processing your return.

Post-Assessment Review

A post-assessment review happens after your return has been processed and you have received your Notice of Assessment. The CRA selects your return for a closer look and asks you to provide receipts or documentation to support specific claims.

This is more common and is the type most self-employed individuals encounter. The CRA reviews millions of returns each year through this program.

Notice of Reassessment

A Notice of Reassessment means the CRA has already changed your return. They have adjusted one or more lines, recalculated your tax owing, and are informing you of the result. This can happen after a review, after matching your return against third-party data (T4 slips, T5 slips), or after finding a math error.

A reassessment may result in additional tax owing, a reduced refund, or occasionally a larger refund if the CRA corrects something in your favour.

Common Reasons the CRA Contacts You

Reason	What It Looks Like
Matching discrepancy	The income on your return does not match T4, T4A, or T5 slips the CRA received from payers
Math or calculation error	The CRA's calculation of a credit or deduction differs from yours
Random selection	Your return was selected through the CRA's random review program
Specific claim review	A particular deduction (home office, vehicle, business expenses) was flagged for verification
Prior year adjustment	Information from a prior year triggered a review of the current year

Being selected does not imply wrongdoing. The CRA conducts random reviews specifically to maintain the integrity of the self-assessment system.

How to Respond to a Review Letter

If you receive a review letter, here is how to handle it step by step.

Step 1: Read the Letter Carefully

The letter specifies exactly what the CRA wants. It will list the tax year, the specific lines or claims under review, and the documents they need. Do not guess or send everything you have. Respond to what they asked for.

Step 2: Gather Your Documentation

Depending on the claim being reviewed, you may need to provide:

• Business expenses: Receipts, invoices, bank or credit card statements showing the transactions
• Home office deduction: Measurements of your workspace, utility bills, mortgage interest or rent statements, property tax bills
• Vehicle expenses: A mileage logbook, fuel receipts, insurance and maintenance invoices, the business-use percentage calculation
• Income verification: Contracts, invoices you issued, bank deposit records

Step 3: Respond Through CRA My Account or by Mail

You have two options for submitting your response:

CRA My Account (recommended):

1. Log in to My Account at canada.ca/my-cra-account
2. Go to "Submit documents"
3. Select the tax year and reference number from the review letter
4. Upload your documents (PDF, JPG, or TIFF format)

By mail: Send your documents to the address on the review letter. Include the reference number and your social insurance number. Use registered or tracked mail so you have proof of submission.

Step 4: Respond Within the Deadline

The review letter gives you a deadline, typically 30 days. If you cannot meet the deadline, call the CRA at the number on the letter and request an extension before the deadline passes. The CRA generally grants reasonable extensions if you ask proactively.

If you do not respond by the deadline, the CRA may reassess your return by disallowing the claims under review.

How to Respond to a Notice of Reassessment

If you receive a Notice of Reassessment, the CRA has already changed your return. Review it carefully.

If You Agree

If the reassessment is correct (for example, you forgot to report a T4A slip), you do not need to do anything except pay any balance owing by the due date shown on the notice. Interest accrues on unpaid balances.

If You Disagree

If you believe the reassessment is wrong, you have two options.

Option 1: Contact the CRA Directly

Sometimes a reassessment is based on incomplete information. Before filing a formal objection, try calling the CRA or responding through My Account to provide the missing documents. This can resolve the issue faster than a formal dispute.

Option 2: File a Notice of Objection

If the CRA maintains the reassessment and you still disagree, you can file a formal Notice of Objection. This is your legal right under the Income Tax Act and the Excise Tax Act.

Filing a Notice of Objection

Deadline

You must file your objection within 90 days from the date on the Notice of Reassessment, or within one year from your filing deadline for the tax year in question, whichever is later.

For most individuals, this means you have until at least one year after the April 30 filing deadline. But do not wait. File as soon as you have your documentation ready.

How to File

Online through My Account:

1. Log in to CRA My Account
2. Select "Register a formal dispute (Notice of Objection)"
3. Follow the prompts to identify the tax year and issues in dispute
4. Upload supporting documents

By mail: Complete Form T400A (Objection - Income Tax Act) or Form GST159 (Notice of Objection - GST/HST) and mail it to the Chief of Appeals at your regional Tax Services Office.

What to Include

Your objection should clearly state:

• The tax year and assessment in question
• The specific items you are disputing
• The facts and reasons you believe the reassessment is incorrect
• Supporting documents (receipts, contracts, calculations)

Be specific. "I disagree with the reassessment" is not sufficient. "I am disputing the disallowance of $4,200 in home office expenses because I maintained a dedicated workspace as documented by the attached floor plan and utility bills" is much stronger.

What Happens After You File

The CRA assigns your objection to an Appeals Officer who was not involved in the original review. The officer reviews your case independently. Possible outcomes:

• The reassessment is reversed (in your favour)
• The reassessment is partially changed
• The reassessment is confirmed (the CRA stands by its decision)

Processing times vary. Simple objections may be resolved in a few months. Complex cases can take over a year.

If You Still Disagree

If the Appeals Officer confirms the reassessment and you still disagree, you can appeal to the Tax Court of Canada within 90 days of the Appeals decision. At this stage, consider consulting a tax professional or tax lawyer.

Your Rights Throughout the Process

The CRA Taxpayer Bill of Rights guarantees that you are:

• Entitled to complete, accurate, and timely information about your tax affairs
• Entitled to claim every benefit allowed by law
• Treated professionally and with courtesy
• Entitled to a formal review process and the right to object

If you feel the CRA has not respected your rights, you can file a complaint with the Taxpayers' Ombudsperson.

Key Takeaways

• A review letter is not an audit and does not mean you did anything wrong
• Respond within the deadline stated in the letter and provide exactly what was requested
• Use CRA My Account for the fastest response and document upload
• A Notice of Reassessment means changes were already made to your return
• You have 90 days to file a Notice of Objection if you disagree with a reassessment
• The Appeals process is independent from the original review team
• Keep organized records year-round so you can respond quickly if selected

Sources

1. CRA — After you file: Reviews and reassessments
2. CRA — File an objection
3. CRA — Taxpayer Bill of Rights
4. CRA My Account — Submit documents
5. Taxpayers' Ombudsperson