If you feel TurboTax has made an error, we guarantee our calculations are 100% accurate. First, try to determine if the error and any penalty/interest is due to a calculation error. You can then follow the instructions below to submit a claim under our 100% Accurate Calculations Guarantee. 

You might be able to find discrepancies by comparing the line numbers and their corresponding values on the  PDF copy of your tax return  that you saved. 

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