Louisiana Form R-210R, Underpayment of Individual Income Tax Penalty Computation, is used by resident filers to determine whether they owe a penalty for not paying enough Louisiana income tax during the year. This may happen if a taxpayer did not make enough estimated tax payments, did not make payments on time, or had too little Louisiana tax withheld.
What is the Louisiana underpayment penalty?
According to the Louisiana Department of Revenue, a 12% annual penalty for underpayment of individual income tax. The penalty may apply if you did not pay enough estimated tax during the year or did not make estimated tax payments by the required due dates. The penalty is calculated separately for each underpaid installment based on the number of days the underpayment was unpaid.
Who may need Form R-210R?
You may need Form R-210R if you were required to make Louisiana estimated tax payments for 2025 and did not pay enough tax during the year through withholding, estimated payments, credits, or an extension payment. Louisiana generally requires estimated payments if your expected Louisiana income tax after credits and withholding is more than $1,000 for single filers or $2,000 for joint filers.
You may also need this form if your income changed during the year and you became required to make estimated payments after the year had already started. In that case, Louisiana may require fewer installments depending on when the requirement was first met.
Estimated Payment Due Dates
For calendar-year taxpayers, Louisiana generally requires estimated tax payments by the following dates:
| Installment | Due date |
| 1st installment | April 15 |
| 2nd installment | June 15 |
| 3rd installment | September 15 |
| 4th installment | January 15 of the following year |
If you were not required to make estimated payments until later in the year because of a change in income, the number of required installments may be reduced.
How does Form R-210R calculate the penalty?
Form R-210R first calculates the required annual payment. For 2025, the required annual payment is generally the smaller of:
- 90% of your 2025 Louisiana income tax liability, or
- 100% of your 2024 Louisiana income tax liability.
The form then divides the required annual payment by the number of required installments and compares each required installment to the payments available for that period. Payments may include estimated tax payments, withholding, credit carryforward, and certain extension payments.
If a period is underpaid and no exception applies, Louisiana calculates the penalty using a 12% annual rate, or a daily penalty rate of 0.0329%.
Are there exceptions to the penalty?
Yes. Form R-210R includes several exceptions that may reduce or eliminate the underpayment penalty.
- Exception 1- You do not owe a penalty: You are not responsible for a Louisiana underpayment penalty if you were not required to make estimated tax payments because your Louisiana tax liability, after applicable credits and payments, does not exceed $1,000, or $2,000 if filing married filing jointly. If this exception applies, Louisiana says the taxpayer does not need to continue with the form.
- Exception 2- Prior year tax liability: This exception may apply if 2025 payments equal or exceed the required percentage of the taxpayer’s 2024 Louisiana tax liability for each installment period. This exception does not apply if the taxpayer was a part-year resident in 2024.
- Exception 3- Prior year income using current year rates: This exception may apply if 2025 payments equal or exceed the tax computed on 2024 income using 2025 tax rates, filing status, and dependents. This exception also does not apply if the taxpayer was a part-year resident in 2024.
- Exception 4- Annualized income: This exception may help taxpayers whose income was not earned evenly throughout the year. It uses actual income received during specific periods and compares the required annualized amount to payments made for the period.
- Exception 5- Installment period income: This exception uses actual taxable income for the months ending before each installment due date. If payments and withholding for the period are enough, the taxpayer may avoid the penalty for that period.
Special rules for farmers and fishermen
Special rules apply if at least two-thirds of the taxpayer’s estimated gross income is from farming or fishing, including oyster farming. These taxpayers may generally make the declaration and estimated tax payment by January 15, without being assessed an underpayment penalty, as long as the declaration payment is at least 66.66% of the estimated tax.
Program Entry
To calculate your Louisiana underpayment penalty, follow the steps below.
- State
- Edit Louisiana using the three dots
- Miscellaneous Forms
- Underpayment of Income Tax, Form R-210R