What does it mean if the CRA reassesses my tax return?

A CRA reassessment means the CRA has reviewed your original tax return and made changes to it — either increasing or decreasing the tax you owe. You will receive a Notice of Reassessment (NoR) by mail or through My Account, showing the adjusted amounts. Reassessments can happen for various reasons: a routine review, information from a third party (like an employer or financial institution), matching of slips reported versus claimed, or a more detailed audit.

If the reassessment results in more tax owing, it also includes any applicable interest and potentially penalties. If it results in a refund, the CRA will pay that to you. The reassessment does not mean you have done anything wrong — many are corrections of errors the CRA itself identified or adjustments based on information that differed from what you reported.

You have the right to object to a reassessment you disagree with. You must file a Notice of Objection within 90 days of the mailing date of the Notice of Reassessment. If you miss this deadline, you can apply to the Tax Court of Canada for an extension, but time limits apply. Do not ignore a Notice of Reassessment — even if you think it is wrong, responding within the window is essential. A tax lawyer or accountant can help you decide whether to object and how to build your case.