TT has an accuracy guarantee. it won't pay any additional taxes you owed, but will reimburse you for any penalties or interest you pay due its incorrect computations. Most errors are due to incorrect taxpayer input, but if you think it was TT calculation errors, file a claim
https://ttlc.intuit.com/community/charges-and-fees/help/how-do-i-submit-a-claim-under-the-turbotax-1...
