Thanks for your reply. To make sure I understand correctly, let's take a look at a couple of examples.
Assume that my estimated quarterly payment is 25k ( x 4 = 100k for the year) for all below scenarios.
Scenario 1: I paid 20k per quarter for first 3 quarters, plus 40k for Q4, and my total tax due is 100k for the year. Will the IRS still assess an underpayment tax penalty because I did not pay 25k per quarter, even though the total payment for the full year is 100K? Or will they assess me interest penalties (but not an underpayment penalty)?
Scenario 2: I paid 20k per quarter for all 4 quarters, and my total tax due is 80k (less than the estimated 100k). Will I owe any underpayment tax penalty or interest penalties?
Scenario 3: I paid 20k + 10k + 20k + 30k =80k for the 4 quarterly payments, and my total tax due is 80k (less than the estimated 100k). Will I owe any underpayment or interest penalties (because I only paid 10k in Q2, which is less than 80k/4 = 20k)?
