If an underpayment penalty is calculated on your tax return, it will be added to the other taxes and netted against your payments.
The underpayment penalty appears on line 24 of the 1040, and it is added by TurboTax into the amount due on line 23 or netted against the amount overpaid on line 20.
[Edited 3/31/2020 2:04 pm CDT - updated for 2019]
