Why would I have an underpayment penalty of $263 of estimated taxes, but I did not estimate taxes for 2017?

[AnnetteB]

The underpayment penalty is assessed if you did not make enough estimated payments or have enough taxes withheld from your income throughout the year to cover your tax liability.  It does not only apply to those who have made estimated payments.

For more details see the information below provided by TurboTax Anthony.

https://ttlc.intuit.com/replies/7250569