What to Do If Your Tax Refund Amount Is Wrong

Tax Refund Amount Wrong? Here’s What to Do

Tax filing mistakes are more common than you might think. If your refund looks off, here's how to determine the cause and what steps to take next.

Income tax season is drawing to a close and your tax return is likely one of the more than 20 million filed in Canada this year.

Even though tax software often does the heavy lifting with calculations and prompts, with so many fields to complete, slips to remember to include and numbers to input, it is not uncommon for human errors to happen during the filing process.

If you realize you made a mistake when filing or think something is off with your tax refund amount, don’t fret — there are a few ways to fix it.

Reasons your tax refund amount might be wrong

Receiving an incorrect tax refund — either your refund was too large, maybe it was less than you were expecting, or perhaps you owe a different amount of money than you thought — can come down to a few things.

Missed or incorrect information entered during the filing process is the most common culprit. Other occurences that might lead to an incorrect refund can include:

A missed slip/a slip arriving after you’ve filed your taxes (such as a T-slip).
Entering an amount incorrectly.
Forgetting to include income (for example, sales from a side hustle or freelance earnings).
Missing a deduction (for example, a charitable receipt or your union dues).

🤓 Nerdy Tip: Using information on file, the CRA can change your return, which can affect your refund. For instance, by including forgotten tuition carry forward amounts. In other cases, if you have a tax or benefits balance owing, the CRA might transfer part or all of your refund to cover these amounts. If things look off, start by reading your notice of assessment, which will explain if the CRA adjusted your return and its reasons for doing so.

How to fix a mistake on your tax return

If you’ve noticed an error or an omission on your tax return, it can be fixed. For example, let’s say you realize you entered the wrong numbers in one of the fields, which led to an incorrect refund amount. There are a few ways to make it right with the CRA:

First of all, if this is something you realized before you received your refund, don’t file another tax return or contact the CRA just yet.

The CRA suggests taxpayers wait until they receive a notice of assessment before requesting any changes (if the CRA has this information on file already, they may make a change to your tax return automatically).

Once you receive your notice of assessment:

Log into your CRA MyAccount and click on ‘Change my return.’ Here, you’ll be able to select the relevant tax year from a dropdown list, add information from tax slips on file with the CRA, or use a search feature to find a particular line in your tax return and enter a new amount.
Submit additional information or documentation to support your change, if necessary. You can not only request to make changes to 2023’s return, but to other returns filed for the 10 past calendar years (i.e.: tax year 2013 or later). You can make changes to returns from more than one tax year in the same session.

If your return was filed electronically, you can also make changes to your tax return through CRA’s ReFILE program, which allows adjustment requests for the four previous tax years through NETFILE or EFILE tax software.

If you’d rather amend your return by mail, send form T1-ADJ Adjustment Request and supporting documents to your tax centre (either Winnipeg, Sudbury or Jonquière, QC, depending on your province or region of residence).

For certain changes, such as a bankruptcy return or changing a return for a tax year that already has a reassessment in progress, your only option is to make a request by mail.

After requesting a change:

After you request an adjustment to your tax return, the CRA will either send you a notice of reassessment or a letter explaining why it did not make the changes you requested or why no changes were needed.

Timelines for responses to adjustment requests are two weeks when you file online and eight weeks when you file by mail.

Keep in mind that while fixing a tax mistake could result in an additional refund, it could also lead to you owing money this year or having to repay some of the refund you were issued after you filed your original return.

If it’s an amount owing, the CRA may also charge interest, if applicable, dating back to the original tax deadline (for example, for 2023 taxes, this would be April 30, 2024). In cases where you disagree with the CRA’s findings or conclusion of your reassessment, you have the right to take things further by filing a Notice of Objection within 90 days of the date of reassessment, or one year after the tax filing deadline, whichever is later.