2025 Illinois Underpayment Warning - Calculation Bug?

Forum|Forum|5 months ago
February 8, 2026
1 reply
37 views

I'm receiving a tax underpayment warning for my 2025 Illinois State Tax return. The tax liability being presented does not include the 4 estimated quarterly tax payments made for the 2025 tax year. I have a refund due when the estimated tax payments are considered. Why am I being alerted to a potential underpayment? Is this a calculation bug or? For now, I'm going to skip the annualization method and take the let Illinois figure out any penalty (if any) to expedite my tax return.

Monikak11

Level 2

Depending on all of the applicable facts, it's still possible to have an underpayment penalty even though you are receiving a refund.

Also, each state's rules may be different. For Illinois, if you:

have a tax liability greater than $1,000 after subtracting your withholding, pass-through withholding payments, and credits, or
were required to make estimated tax payments and failed to pay the required amount by the payment due dates, you may owe a late-payment penalty for underpayment of estimated tax. See Form IL-2210 for details.

Check to see whether all of the state estimated payments were entered. Navigate to the estimated tax payments section:

TurboTax Online/Mobile: Go to estimated tax payments under Deductions & Credits.
TurboTax Desktop: Go to the Federal Taxes, then Deductions & Credits. Select Estimates and Other Taxes Paid.
Select Start or Revisit next to the type of estimated tax payment you'd like to enter under Estimated Tax Payments.

VollpreussAuthor

Level 3

Thank you for the prompt and thorough response. A bit to think about here.

To confirm, I did enter 4 Estimated Tax Payments for the Illinois return. The running Illinois Tax Refund amount at the top of the screen included the 4 estimated tax payments.

When I click Forms to understand the unexpected Tax Liability Balance being presented, I see the Tax Liability, all Payments, and an Overpayment amount. There is no explanation or context provided for the displayed Tax Liability amount. Thus, my original post.

The Underpayment Penalty screen seems to be following the logic of IL-2210 form which initially calculates a lability not including estimated tax payments. (Line 5 result.)

I am of the strong opinion this screen needs improvement such that direct support and explanation is provided for the displayed Tax Liability amount, so the user doesn’t have to wonder and calculate like me.

Thanks.

AmyC

Level 15

We at Intuit TurboTax want our users to be completely delighted with their experience using our products and services, and successful in their financial lives and businesses.

Once you file your return, as long as the settings to receive communication from Intuit don’t block it, you will see a pop-up message or receive an email with a survey asking you about your experience. We encourage you to leave your notes and comments there. “Voice of the Customer” notes and comments are read and acted upon.

If you are using TurboTax Desktop, you can also leave feedback at the Final Steps tab.

**Say "Thanks" by clicking the thumb icon in a post. **Mark the post that answers your question by clicking on "Mark as Best Answer"