Sometimes Canada Revenue Agency (CRA) changes your return after you filed it. The question about what to do depends on whether CRA is right or not.
If you use a tax preparer you should send this notice to the person who did your tax return, and they will deal with it. If you did your own return, the rest of this is for you.
What if CRA is Right?
Many times when CRA makes a change to your return they are correcting an error you made or adding income you should have included.
What if CRA is Wrong?
If CRA has added income to your return which is not yours or which you have already included in your return, you need to contact CRA to resolve the issue or object to their assessment of your return.
Notice of Objection to File if CRA is Wrong
You have 90 days to file a notice of objection to a tax assessment when you believe CRA is wrong. If you do not object within that time period, you could lose your ability to object at all.
The form you need is the T400A, which is available on the CRA website. If CRA changes your return and they are correct, there is nothing you need to do. If CRA is wrong, you need to attempt to resolve the problem by contacting them. If you cannot resolve the issue within 90 days you need