The underpayment penalty is for your 2024 return that you're filing now. The IRS wouldn't have calculated the penalty yet to send any notices.
The underpayment penalty applies when you owe at least $1,000 and didn't pay enough estimated tax during the year. You can either pay through withholding or direct payments to the IRS.
To avoid the penalty for 2024, you have to pay at least:
- 90% of your 2024 tax liability or
- 100% of your 2023 liability (110% if your income is $150,000* or more)
*$75,000 if your filing status is Married Filing Separately