Taxes owing on CRA higher than what Turbotax shows

Since your return has already been accepted by the Canada Revenue Agency (CRA), when you receive your Notice of Assessment (NOA) (not the express) you will be able to ask the CRA or view your NOA to know what calculation was corrected. You can contact the CRA at 1-800-959-8281 once you receive your NOA to clarify if it was in fact a calculation error.

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My NOA has been received and the information provided still says it was a calculation error. It doesn't go in to any detail. As mentioned, my taxes are very basic. Now there is a 3 hour wait to get in touch with a CRA agent. What could possibly have caused such a large calculation error between turbotax's information and the CRA?

Unfortunately, we cannot view your return in this public forum. The Canada Revenue Agency (CRA) is the best avenue to find out the changes that were made and the reason. This information will be needed if you would like to make a claim under the TurboTax 100% Accurate Calculations Guarantee. To do so, please see this FAQ: How do I submit a claim under the TurboTax 100% Accurate, Expert Approved Guarantee? 

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And to confirm, under your accurate calculations guarantee, you only cover penalties and interests associated with the miscalculation and not the difference in the amounts owing? 

Yes, you are correct, if found to be an error on our part. The amount owing would still have been owed even without a miscalculation. We pay the interest or penalties if a miscalculation was on our part, because it may have been due and paid on your part at an earlier time if you would have known earlier. This can only be investigated and resolved by applying for the guarantee.

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