How Far Back Can the CRA Audit or Reassess You? Time Limits Explained

After the CRA assesses your return, it has a limited time to reassess it. Subsection 152(3.1) of the Income Tax Act calls this the normal reassessment period:

• Three years for individuals, Canadian-controlled private corporations (CCPCs) and trusts other than mutual fund trusts.
• Four years for corporations that are not CCPCs and for mutual fund trusts.

The period runs from the earlier of the date of the original notice of assessment and the date of the notification that no tax is payable. After it ends, the year is "statute-barred" and the CRA generally cannot reassess it unless an exception applies.

Note the difference between an audit and a reassessment. The CRA can ask questions about any year, including to decide whether an exception applies. What is limited is its power to change a statute-barred year.

• Misrepresentation or fraud. The CRA can reassess outside the normal period if you made a misrepresentation attributable to neglect, carelessness or wilful default, or if you committed fraud. The CRA must prove it. There is no fixed time limit once it is established.
• A waiver. If you sign a waiver (Form T2029) within the normal period, the CRA can reassess the matters you named in the waiver after that period. You can ask to limit or revoke a waiver. Do not sign one without understanding it.
• Extra three years in listed cases. The Act adds three years in situations such as a transaction with a non-resident with whom you did not deal at arm's length.
• Returns never filed. If you never filed a return for a year, the CRA has not issued an original assessment, so the clock does not start in the usual way. See unfiled tax returns.
• GST/HST and payroll. These have their own limits. GST/HST reassessments generally have a four-year limit, and payroll deductions have their own rules.

The time limit works in one direction for the CRA and in another for you. Individuals and graduated rate estates can ask the CRA to reassess a year, for the limited purpose of getting a refund or reducing an amount payable, up to 10 calendar years after the end of the tax year. The CRA's taxpayer relief provisions are the route. The relief is discretionary, so you ask, and the CRA decides. See taxpayer relief provisions.

When the CRA reassesses a statute-barred year, it will say you made a misrepresentation or that you were careless. It must prove that you made a misrepresentation that was attributable to neglect, carelessness or wilful default. Common situations are unreported income, overstated expenses, missed foreign reporting, or errors in a rental or business return.

• Check the date on the original notice of assessment and compare it to the reassessment date.
• Ask the CRA to explain in writing what it says was misrepresented.
• Gather your records, including the information you gave your accountant.
• File a notice of objection on time if you disagree. See what to do if you receive a CRA reassessment.
• If the CRA confirms its position, you can appeal to the Tax Court of Canada.

If you know a past return was wrong, a voluntary disclosure to the CRA may reduce penalties and, in some cases, interest, but only if the application is voluntary and complete and meets the program's conditions. The conditions changed in October 2025, so check the current rules before you apply. See voluntary disclosures and our voluntary disclosure service.