Filing changes to your tax return

What do you do if there’s an error on your tax return?

Thanks to Tim Cestnick, managing director of WaterStreet Family Wealth Counsel, for the following article extract, published in The Globe and Mail, April 28, 2010.


Making Changes. You send in your tax return thinking all is well and then discover after the fact that another T-slip arrives in the mail a few days later. Or perhaps you’re going through your files from last year’s tax return and discover some receipts that should have been kept in this year’s file – so they were missed when you prepared this year’s return (you did check last year’s file, didn’t you?).

Could it be you didn’t forget anything, but simply made a mistake? Common mistakes include failing to transfer certain tax credits to a family member to save more tax (age, disability, pension, tuition, education, textbook, public transit and donation tax credits come to mind), forgetting some types of business expenses (did you claim capital cost allowance on your computer, desk or owned vehicles used in business?), forgetting safety deposit box fees, among other mistakes.

If you did forget something, or made a mistake, you can easily make a change by filing Form T1-ADJ (called an “adjustment request”). It’s a one-page form where you simply make note of the lines on your tax return you’d like to change, provide an explanation at the bottom, and send it in. No need to file a complete amended tax return. You’ll find a copy of Form T1-ADJ on the Canada Revenue Agency’s (CRA’s) website at cra.gc.ca.

Fighting Your Cause. Once you’ve filed your tax return, you can expect to receive a Notice of Assessment within three to five weeks. If your tax return is not assessed as you filed it, you should take a close look at the change until you understand why the change was made. Speak to CRA to more fully understand the change if you have to.

If you disagree with your Notice of Assessment, you’ve got two courses of action to consider. Your first step should be a phone call to CRA to resolve the issue by phone if you can.

If that doesn’t work, then you may want to file a Notice of Objection. You can use Form T400A to file your objection, which I like to do, but it’s not necessary. You can also file an objection by stating in a letter the facts, your reasons for objecting and the change you’re requesting. Address your letter to the chief of appeals at your local tax services office or taxation centre.

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