CRA Audit Guide 2026 | What to Do

Understanding CRA Reviews and Audits

The Canada Revenue Agency uses the term "review" for most post-filing scrutiny. These reviews are a normal and ongoing part of the CRA's compliance programs. Understanding the different types of reviews helps you prepare mentally and practically for what's ahead.

Processing Review (Pre-Assessment)

A processing review happens before the CRA issues your Notice of Assessment. During this stage, CRA staff may request additional information to verify claims on your return—such as charitable donation receipts, medical expense documentation, or home office calculations. The CRA is simply confirming your information is complete and accurate before finalizing your assessment. These reviews are typically resolved through correspondence and rarely escalate further.

Desk Audit

A desk audit is the most common type of CRA review and is handled entirely by mail, phone, or online. A CRA tax auditor works from a Tax Services Office and focuses on specific claims rather than your entire return. Common targets for desk audits include:

• Medical expenses
• Charitable donations
• Home office deductions
• Vehicle and transportation expenses
• Rental property statements
• Business deductions

Desk audits are typically less intensive and can often be resolved through documentation submission without face-to-face contact.

Field Audit

A field audit is more comprehensive and involves a CRA auditor visiting your home, office, or business location in person. This type of audit examines your complete tax situation across multiple years and may look at your overall financial records, books, and supporting documentation. Field audits typically last anywhere from six to eighteen months, depending on complexity. They're more common for businesses, self-employed individuals, and situations involving significant income or deductions.

Specialized Audits

Beyond standard income tax audits, the CRA conducts focused reviews in specific areas:

• GST/HST audits: Verify proper collection, remittance, and claiming of goods and services tax
• Payroll audits: Ensure employers correctly deduct and remit income tax, CPP contributions, and EI premiums

What Triggers a CRA Audit?

Understanding why you might be selected can help you prepare defensible tax positions in the future. The CRA uses a sophisticated risk assessment system to prioritize files.

Red Flags and Risk Factors

• Unusual deductions: Claims significantly higher than average for your income level or industry
• Inconsistent reporting: Deductions reported in one year but not others without explanation
• High business expenses: Home office, vehicle, or entertainment expenses that appear excessive
• Cash-based businesses: Restaurants, retail, professional services, and other businesses with significant unreported cash income risk
• Large charitable donations: Especially donations valued using appraisals rather than receipts
• T776 rental income claims: Losses claimed year after year on rental properties
• Foreign income: Unreported foreign property, accounts, or income
• Investment losses:
Frequent trading, margin accounts, or derivative losses

Random Selection and Data Matching

Not all audits are triggered by red flags. The CRA also:

• Randomly selects files as part of ongoing compliance programs
• Compares your information to similar taxpayers and industry benchmarks
• Cross-references data from T4s, T5s, T1 Generals, T2125s, and other slips filed by employers and institutions
• Analyzes patterns across multiple audit files to identify systemic compliance issues

In other words, being audited doesn't necessarily mean the CRA suspects wrongdoing—sometimes you're selected simply as part of their routine verification process.

Your Rights During a CRA Audit: The Taxpayer Bill of Rights

Canada's tax system is built on fairness, and the CRA has committed to 16 fundamental taxpayer rights. Knowing these rights protects you throughout the audit process.

Your Right	What It Means
Professional Service	You deserve courtesy, respect, and professional treatment from all CRA personnel
Accurate Information	The CRA must provide you with complete, accurate, and clear information about your tax obligations
Preferred Language	You have the right to communicate in English or French throughout the audit process
Representation	You may have a representative (accountant, lawyer, or tax agent) present during all communications
Confidentiality	Your personal and financial information is kept confidential and protected under privacy laws
Fairness	The CRA applies tax law consistently and gives you a fair opportunity to provide your position
Right to Appeal	You may dispute a reassessment through the Notice of Objection and appeal processes

What to Prepare: Essential Documentation

The moment you receive a CRA notice of audit, your focus shifts to organization and documentation. The principle is simple: if you claimed it, you must be able to prove it.

Core Documents to Gather

• Original receipts and invoices: Physical or digital copies of all purchases supporting deductions you claimed
• Bank and credit card statements: Full statements for the relevant tax year showing deposits, expenses, and transfers
• Mileage log: For vehicle expenses, a detailed log showing business vs. personal use (preferably contemporaneous records)
• Home office calculations: Rent/mortgage, utilities, property tax, and home insurance statements; square footage calculations showing percentage of business use
• Business records: General ledger, journal entries, invoices issued, receipts for expenses, and payroll records
• T4s, T5s, and other slips: All income-reporting documents for the relevant year
• Professional fees: Receipts for tax preparation, accounting, or legal advice
• Charitable donation receipts: Original receipts from registered charities (not screenshots or summaries)
• Medical expense documentation: Prescriptions, receipts, and medical practitioner confirmations for eligible expenses
• Rental property documents: Mortgage statements, property tax notices, insurance invoices, and repair receipts

Organization Strategy

Don't simply dump a box of documents on the auditor. Instead:

1. Organize by category: Group documents by claim type (home office, vehicle, charitable donations, etc.)
2. Create a summary: For each claim, prepare a one-page summary showing total claimed, supporting documents, and calculation method
3. Use chronological order: Arrange receipts by date within each category
4. Label clearly: Use tabs, dividers, or digital indexing so the auditor can easily reference your supporting materials
5. Keep originals: Provide photocopies if requested; keep originals for your records

How to Respond: Timelines and Process

A CRA audit follows a structured timeline, and meeting deadlines is critical. Missing a response deadline can result in reassessment without your input.

Initial Contact and Response Timeline

When the CRA initiates an audit, you'll typically receive a letter outlining:

• The tax year(s) under review
• The specific areas being examined
• A list of documents or information being requested
• A deadline for your response (usually 30 days, sometimes 90)
• Contact information for the assigned auditor

Read the request carefully. The deadline is not a suggestion—it's a legal requirement. If you need more time, contact the auditor immediately to request an extension. Extensions are often granted if you have a reasonable explanation.

Desk Audit Response

For a desk audit, you'll submit your documentation by mail, email, or through the CRA's online portal. Once submitted:

1. The auditor reviews your materials
2. They may request clarification or additional documents
3. The review concludes with either acceptance of your position or proposed adjustments
4. The CRA issues a Notice of Assessment or Reassessment

Field Audit Response

For a field audit, the auditor will schedule an initial meeting at your location. Bring the auditor to a quiet, organized space where you can discuss your records. During the meeting:

• Introduce the auditor to the relevant staff (bookkeeper, office manager)
• Provide access to books, records, and supporting documents
• Answer questions directly and honestly
• If you don't know an answer, say so and offer to follow up in writing
• Have your representative (accountant or lawyer) present if possible

The auditor will likely conduct follow-up visits and request additional information by mail. Respond promptly to all requests to demonstrate cooperation and good faith.

When to Hire a Professional

Not every audit requires professional representation—a simple desk audit of a straightforward deduction might be manageable on your own. But several situations warrant hiring an accountant or tax lawyer.

Consider Professional Help If:

• It's a field audit: The complexity and duration justify professional costs
• Large amounts are at stake: If potential reassessments exceed $10,000, professional guidance protects your interests
• Complex business issues: Self-employed, corporate, or partnership audits almost always benefit from representation
• Multiple years under review: Coordinating across several tax years requires expertise
• The auditor proposes significant adjustments: Professional intervention can challenge unsupported CRA positions
• You feel uncomfortable or overwhelmed: Your peace of mind has value

The Notice of Objection Process

If you disagree with the CRA's reassessment, you don't have to accept it. The Notice of Objection is your formal dispute mechanism.

Filing Timeline

You have 90 days from the date on your Notice of Assessment or Reassessment to file a Notice of Objection. If you miss this deadline, you may still apply for an extension up to one year after the original filing deadline, but extensions aren't guaranteed. File promptly to protect your rights.

What to Include

Your Notice of Objection (Form T400A) must include:

• Your name, address, and Social Insurance Number
• The tax year in question
• A clear description of the CRA's adjustments you're contesting
• Your reasons for disagreeing with each adjustment
• Supporting documentation showing why your original position was correct

Processing Timeline

CRA processing times for objections vary by complexity:

Complexity Level	Average Processing Time (2026)
Low (simple deductions)	125 days
Medium (business issues)	365 days (1 year)
High (complex technical matters, large corporations)	18–24 months or longer

During the objection period, you can still provide new evidence or arguments. The CRA will assign an Appeals Officer (different from the original auditor) to review your case. This fresh perspective often helps resolve disputes fairly.

After Objection: Appeal to Tax Court

If the CRA upholds its position after the objection review, you have a further right to appeal to the Tax Court of Canada. This is a formal court process and definitely requires legal representation. However, most disputes are resolved during the objection phase without escalating to court.

Avoiding Penalties and Interest

Beyond reassessing tax owing, the CRA can impose penalties and charge interest. Understanding these helps you minimize the financial impact.

Penalties

• Failure to report penalty: 50% of unreported income (sometimes up to 200% for gross negligence)
• Penalty for false statements or omissions: Up to 50% of understated tax if due to negligence
• Gross negligence penalty: Applies if you knowingly misrepresent your tax situation; 50% of underpaid tax with a $11,745+ minimum (2026)

Interest

The CRA charges compound daily interest on reassessed tax owing. The rate is set quarterly (currently around 8–9% annually). Interest accrues from the original due date of the return to the payment date.

Penalty Relief

If you have a good reason for the error—such as relying on incorrect professional advice or a genuine misunderstanding of the rules—you can request Taxpayer Relief. The CRA may waive penalties (though rarely interest) if you acted in good faith. This must be requested within two years of the reassessment.

Key Takeaways

• Understand that reviews and audits are routine; being selected doesn't imply wrongdoing
• Know your Taxpayer Bill of Rights and exercise them confidently
• Gather and organize documentation immediately upon receiving a notice
• Respond to all CRA requests within the specified timeframe
• Consider professional representation for field audits or complex situations
• If you disagree with a reassessment, file a Notice of Objection within 90 days
• Track deadlines carefully—extensions aren't automatic
• Request Taxpayer Relief if penalties result from good-faith errors

Moving Forward: Build Audit-Proof Records

The best defense against audit complications is prevention. Going forward, adopt record-keeping practices that will withstand CRA scrutiny:

• Keep all receipts for at least 6 years (CRA's standard retention period)
• Use contemporaneous records like mileage logs and time sheets—not reconstructed records
• Maintain business-use documentation explaining the business purpose of expenses
• Separate personal and business expenses clearly in your bookkeeping
• Work with a professional to ensure your claims align with CRA guidance
• Report all income from all sources—the CRA cross-checks T4s, T5s, T1 Generals, and other documents