Alabama Underpayment Penalty

[Needtaxhelp13]

Why am I being asked about the underpayment penalty with the state of Alabama when I am getting a refund with the state of Alabama? 

[MaryK4]

In TurboTax, you can receive a refund while still owing an Alabama Underpayment Penalty because the tax system is "pay-as-you-go". This penalty is based on when you paid your taxes during the year, not just your final total.
 

If you earned a large amount of income early in the year but did not have enough tax withheld or make estimated payments until the very end of the year, you underpaid for those specific quarters.  Alabama requires you to pay at least 90% of your current year's tax or 100% of your previous year's tax in equal installments throughout the year. If any quarterly payment was too low, a penalty is triggered for that period, even if your total payments eventually exceeded your tax bill.