The penalty for late paying is 5% of the amount you owe, for each month or part of a month, for the first 5 months, then 1/2% per month after that. So being even 1 day late, the penalty will be 5% of what you owe. There are some minimum penalties that can be more than 5% if you are more than 60 days late.
The penalty for late filing is 1/2% per month, but this penalty is not assessed for any month when you are also assessed the full 5% late payment penalty.
You will also be charged interest on the late amounts (tax plus penalty) at about 4% APR.
However, I would not pay a penalty now, even if Turbotax attempts to calculate it. Wait until the IRS sends you a bill. Then, you can request penalty relief for cause or if this is the first time you ever owed a penalty.
https://www.irs.gov/businesses/small-businesses-self-employed/penalty-relief-due-to-first-time-penal...
