CRA Audit: What to Expect and How to Prepare

A CRA audit is a detailed examination of your tax filings to confirm that income was properly reported and that deductions and credits were valid. Most taxpayers will never face a full audit; far more common is a lighter review, where the Canada Revenue Agency simply asks you to send supporting documents for something on your return. In either case, the best preparation is the same: organized records kept throughout the year, prompt and accurate responses, and professional help when the amounts or issues are significant.

This general guide explains how the process typically unfolds, what to keep, and how to respond with composure if your file is selected. It is educational rather than specific advice, so confirm your own situation with an accountant.

Reviews versus audits: not the same thing

The word audit causes alarm, but most contact from the CRA is not a full audit at all. It helps to distinguish the main types of review.

Type	What it is	How involved
Matching review	Automated check that your return matches third-party slips	Low; often resolved by mail
Pre-assessment review	A check before your return is assessed	Low to moderate
Processing review	A request for documents after assessment	Moderate
Audit	A thorough examination of books and records	Higher; can span multiple years

A review is usually a targeted request: show us the receipt for this donation, or confirm these medical expenses. An audit is broader and may examine several years, request your books, and involve interviews or a visit for business taxpayers. The great majority of individuals who hear from the CRA are dealing with a review, not an audit.

Why returns get selected

Selection is often misunderstood as a sign of suspicion. In reality, returns are flagged for many reasons, most of them impersonal:

• Random selection. A portion of reviews are simply random, to keep the system honest.
• Mismatched information. Your reported income does not match the T4, T5 or other slips the CRA already holds.
• Certain deductions and credits. Some claims, such as large charitable donations, employment expenses or rental losses, are reviewed more often.
• Unusual changes. A sharp year-over-year change in income or deductions can prompt a closer look.
• Industry or pattern factors. For business owners, certain sectors or reporting patterns attract attention.

Being selected does not mean you have done anything wrong. Many reviews conclude with no change at all once the requested documents are provided.

Keep records year-round, not at tax time

The single best protection against the stress of a CRA review is to keep good records continuously, so that producing a document is a matter of retrieval rather than reconstruction. As a general rule, keep your tax records and supporting documents for six years from the end of the tax year to which they relate.

Records worth keeping in an organized form include:

• Income slips (T4, T5, T3 and others) and anything not reported on a slip.
• Receipts for deductions and credits, such as donations, medical expenses, childcare and employment expenses.
• Records supporting RRSP, FHSA and other registered contributions.
• Investment records, including purchase and sale confirmations that establish your adjusted cost base.
• For business and rental activity, invoices, expense receipts, mileage logs and bank statements.

Some records should be kept well beyond six years. Documents that establish the cost of a property or a long-held investment matter whenever you eventually sell, because they determine the capital gain. This is particularly relevant for anyone relying on the principal residence exemption or tracking the cost base of a rental property. When in doubt, keep rather than discard.

How to respond if you are contacted

A calm, methodical response resolves most reviews without difficulty. The following approach serves taxpayers well:

1. Read the letter carefully. Note exactly what is being asked and the deadline, which is often 30 days.
2. Do not ignore it. Missing the deadline can lead the CRA to disallow the item and reassess, which is harder to reverse than it is to prevent.
3. Gather only what is requested. Provide the specific documents asked for, clearly labelled. There is rarely a need to volunteer more.
4. Keep copies of everything. Retain a copy of what you send and a record of how and when you sent it.
5. Respond in writing where possible. A documented paper trail protects you and keeps the matter clear.
6. Ask for more time if needed. If you cannot meet the deadline, contact the CRA before it passes to request an extension.

If the request is straightforward and the amounts are modest, many taxpayers handle it themselves. Where the matter is larger, spans a business, or involves a judgment call about what is deductible, it is worth involving your accountant before you reply. A well-framed first response often prevents a review from escalating.

If you disagree with the outcome

If the CRA reassesses your return and you believe the result is wrong, you have recourse. You can first ask for an explanation or provide additional information. If that does not resolve matters, you generally have the right to file a formal notice of objection, usually within 90 days of the reassessment for individuals. Beyond that, further appeal routes exist. Deadlines here are strict, so act promptly and consider professional advice, because the process becomes more formal at each stage.

It is also worth knowing that the CRA offers a Voluntary Disclosures Program for taxpayers who come forward to correct past errors or omissions before being contacted. Where it applies, it can reduce penalties, but the rules are specific and professional advice is strongly recommended before using it.

Reducing your audit risk in the first place

You cannot eliminate the chance of a routine review, nor should that be the goal. But you can reduce avoidable friction and the risk of a reassessment:

• Report all income. Ensure every slip is included; the CRA already has copies and matching is automated.
• Claim only what you can support. A deduction you cannot document is a deduction worth reconsidering.
• File on time and accurately. Late or inconsistent filings draw attention.
• Keep business and personal finances separate. For owners, clean separation makes any review far simpler.
• Be reasonable. Claims that are out of step with your income or industry invite scrutiny.

Sound tax planning is not about flying under the radar; it is about claiming everything you are legitimately entitled to while being able to stand behind every number. Our broader guidance on how to reduce taxes in Canada and, for owners, reducing taxes for business owners is written in exactly that spirit.

It also helps to understand how the CRA gathers information, because much of its review activity is simply cross-checking. Employers, financial institutions and other payers file slips reporting what they paid you, and the CRA matches those against your return automatically. International information-sharing agreements mean foreign account and income data increasingly flows to the CRA as well. The practical implication is straightforward: assume the CRA already has a copy of anything reported on a slip, report all of it, and keep the supporting documents for anything that is not on a slip. Transparency is not only the honest approach; it is also the one least likely to generate friction.

How Kevin Hayes Financial Services can help

While audits are handled by accountants and tax specialists, much of the stress they cause is avoidable with good organization and coordinated planning. Our tax planning work helps clients keep clean records, document the cost base of investments and property, and structure their affairs so that a review, if it comes, is a matter of retrieving a file rather than reconstructing a year. Where specialist tax representation is needed, we help clients engage the right professional.

If you would like your financial affairs organized so that a CRA request would be simple to answer, book a private consultation and we will review how your records and planning stand today.