How Far Back Can the CRA Audit You? (2026 Guide)

For most individual taxpayers and Canadian-Controlled Private Corporations (CCPCs), the Canada Revenue Agency can reassess your tax return up to 3 years from the date of the original Notice of Assessment. For other corporations, the period is 4 years. In cases involving loss carrybacks or foreign property, CRA can go back 6 years. And if CRA suspects fraud or misrepresentation, there is no time limit.

Understanding these reassessment windows is essential for knowing how long you need to keep records, when you are "in the clear" for a given tax year, and what your rights are if CRA contacts you about an older return.

Reassessment Period Summary

The Standard 3-Year Reassessment Period

Under subsection 152(3.1) of the Income Tax Act, CRA's standard "normal reassessment period" is 3 years from the date of mailing of the original Notice of Assessment for individuals and CCPCs, and 4 years for other corporations.

This means if you filed your 2023 personal tax return and received your Notice of Assessment on June 15, 2024, CRA can reassess that return until June 15, 2027.

It is important to note that the clock starts from the date of the Notice of Assessment, not from the filing deadline or the date you filed. If you filed late and received your assessment on a later date, the reassessment period extends accordingly.

Within this 3-year window, CRA can review any aspect of your return, income, deductions, credits, and supporting documentation. After the period expires, CRA generally cannot issue a reassessment unless one of the extended periods applies.

The 6-Year Extended Reassessment Period

Several situations allow CRA to reach back 6 years instead of 3:

• Loss carryback claims: If you carry a loss back to a prior year, CRA can reassess the prior year within 3 years of the date you filed the return that created the loss, effectively extending the window.
• Foreign property reporting (Form T1135): If you hold specified foreign property with a total cost exceeding $100,000 at any time during the year and you either failed to file Form T1135 or did not report the income from that property, CRA can reassess up to 6 years from the date of the original assessment.
• Transfer pricing: If your transactions with non-arm's length non-resident parties are reassessed under the transfer pricing rules, the reassessment period is extended to 6 years.

The 10-Year Taxpayer Relief Window

The 10-year period is often confused with CRA audit powers, but it is actually a taxpayer relief measure. Under subsection 152(4.2) of the Income Tax Act and the CRA's taxpayer relief provisions, you can request adjustments to your returns for up to 10 calendar years back.

This is useful if you forgot to claim a deduction or credit, made an error on a past return, or discovered that you overpaid tax in a prior year. You submit a T1-ADJ request (or use CRA's Change My Return online service), and CRA may reassess the return in your favour.

This 10-year window does not give CRA additional audit power, it is a relief mechanism for taxpayers. For details on how CRA uses the 10-year rule, see our dedicated guide on the CRA 10-year limit.

No Time Limit: Fraud and Misrepresentation

Under subsection 152(4)(a)(i) of the Income Tax Act, CRA can reassess at any time if the taxpayer "made any misrepresentation that is attributable to neglect, carelessness, or wilful default or has committed any fraud in filing the return or in supplying any information under this Act."

This is the broadest reassessment power, and it has no time limit. CRA has successfully reassessed returns more than 10 years old under this provision.

What constitutes "misrepresentation" is broader than outright fraud. It includes failing to report income (even unintentionally, if it resulted from neglect or carelessness), making false claims for deductions or credits, and providing misleading information to CRA.

If you are concerned about potential misrepresentations in past filings, the CRA's Voluntary Disclosures Program (VDP) allows taxpayers to come forward and correct errors before CRA discovers them. A successful VDP application can result in reduced penalties (though interest will still apply). Our tax compliance team can advise on whether a voluntary disclosure is appropriate for your situation.

How Long Must You Keep Tax Records?

CRA requires that you retain all books, records, and supporting documents for at least 6 years from the end of the last tax year they relate to. For example, records for your 2025 tax year must be kept until at least December 31, 2031.

If you have filed an objection or appeal, you must keep records until the matter is fully resolved and the time for further appeal has expired. If you have not filed a return for a particular year, there is no time limit on how long records must be retained.

For practical purposes, many accountants (including our team at LedgerLogic) recommend keeping records for 7 years to provide a buffer, and keeping records indefinitely for any year in which there may be a risk of misrepresentation allegations.

What Triggers a CRA Audit?

While this page focuses on reassessment time limits, it is helpful to understand what prompts CRA to look at your file in the first place. Common triggers include large year-over-year changes in income or deductions, claims that are unusual for your industry or income level, inconsistencies between reported income and information from third-party slips (T4, T5, etc.), repeated errors or late filings, and random selection through CRA's risk assessment system.

For a more detailed discussion of audit likelihood and how to reduce your risk, see our guide on the chances of getting audited by CRA.

Your Rights During a CRA Audit

If CRA contacts you about an audit, you have specific rights under the Taxpayer Bill of Rights, including the right to be treated professionally, the right to complete and accurate information about your obligations and entitlements, the right to privacy and confidentiality, and the right to object to an assessment and appeal to an independent body.

You are also entitled to have a representative (such as a CPA or tax lawyer) deal with CRA on your behalf. For a complete guide to navigating the audit process, see our article on how to deal with a CRA audit.

If CRA has assessed penalties as part of a reassessment, you can learn about the specific penalty provisions in our guide to CRA audit penalties.

Keeping records that survive the six years

The six-year retention rule is where most audit trouble actually starts: the CRA asks for a receipt from year four and the business has a bank line, a faded thermal slip or nothing. What holds up is a digital copy of every receipt and bill attached to the ledger entry it supports, with the GST/HST shown, stored where it cannot be lost when a phone dies or a bookkeeper leaves. That is the job Dext does: photograph or forward the receipt, it reads the supplier, date, amount and tax, and files it against the transaction in Xero or QuickBooks, so six years later the auditor's request is a search, not a scramble. Through our link it is 90% off for 3 months. For the ledger itself, Xero keeps an audit trail of every change; our Xero GST/HST setup guide covers the tax settings a reviewer checks first, and our guide to your odds of a CRA audit covers what actually triggers one.

Frequently Asked Questions

Can the CRA audit more than 3 years back?

Yes. The normal reassessment period is 3 years from the notice of assessment (4 years for corporations that are not Canadian-controlled private corporations), but it extends to 6 years for reassessments involving non-arm's-length non-residents or loss carrybacks, and there is no limit where the CRA can show misrepresentation attributable to neglect, carelessness or wilful default, or fraud.

Is there a statute of limitations on CRA audits?

For ordinary errors, effectively yes: once the normal reassessment period has passed, the CRA cannot reassess the year unless you signed a waiver or an exception applies. There is no limitation where misrepresentation or fraud is involved, and the CRA can review a statute-barred year to check the figures it carries into an open year.

How far back can the CRA audit a small business?

The same 3-year normal period applies to a Canadian-controlled private corporation and to a sole proprietor, measured from each year's notice of assessment. Because the CRA can extend to 6 years in some cases and records must be kept for 6 years, a small business should assume six years of books can be requested.

Can the CRA audit you after 10 years?

Only where it can show misrepresentation or fraud, in which case there is no time limit. Ten years is the taxpayer relief window in the other direction: you can ask the CRA to cancel penalties and interest or accept a late election up to 10 calendar years back.

What triggers a CRA audit?

Figures that do not match third-party slips or GST/HST returns, expenses out of line with your industry, repeated losses, large or round-number claims, cash-heavy businesses, shareholder loan balances, and tips. Filing on time with reconciled books and receipts behind every claim removes most of the risk.

How long do you need to keep tax records in Canada?

Six years from the end of the last tax year they relate to, for the return, the books and every supporting document. Records about property or long-term assets must be kept until six years after the year the asset is disposed of. Keep them in Canada, in paper or accessible electronic form.