Let’s say you made no estimated tax payments for the year.

Your tax pro told you to pay $25,000 with each of the four installments. But you have done nothing as of October 1.

Bad you—now you are in the penalty box. If you don’t do something special, you will pay a 7 percent non-deductible penalty on the underpaid amounts.

Example. Your April 15, 2025, penalty will be $1,812.53 if you pay it on April 15, 2026, when you file your return, which is actually 7.25 percent of the original payment because the ... Log in to view full article.