Louisiana’s long-anticipated Combined State and Local Sales Tax Return is now live beginning with the January 2026 return, due February 20th. For in-house tax directors at mid-size and large companies, this is one of those transitions that may present additional challenges. The combined return is administered by the Louisiana Uniform Local Sales Tax Board (the “ULSTB”). Because some early users have reported system errors, a taxpayer that intends to file using the combined return should consider accessing the system as soon as possible, to mitigate the risk of late filings.

Here’s a practical breakdown of what’s changed.

The Big Change: One Return

The key improvement is that businesses can now file a single combined return for both state and local parish sales and use tax returns. This replaces the prior system of filing separate returns by parish. This should significantly improve compliance efficiencies by consolidating reporting into one workflow.

Deadlines

Local sales tax returns remain due on the 20th of each month, with the first combined return due on February 20th for January activity. Although the system is technically live, many users are experiencing technical challenges. While ULSTB has indicated that additional state guidance is expected, thus far they have not issued formal guidance regarding penalty and interest relief as a result of the implementation of the new combined return. As a result, there is a risk a taxing authority could assert that a taxpayer is subject to interest and penalties on a late or incorrect filing even if the errors are attributable to system limitations. A taxpayer should document any late or incorrect filings caused by system limitations in the event the taxpayer needs to contest any improperly applied interest or penalties.

Filing Frequency

One of the significant requirements to using the combined return is that all accounts included in a combined return align in filing frequency to the jurisdiction with the most frequent filing. This means a taxpayer that previously filed some returns on a quarterly basis and others on a monthly basis, the filing frequency for quarterly returns will need to be changed to a monthly in order to be included in a single combined filing. The system will not allow a return to be submitted if filing frequencies are inconsistent.

Gross Receipts Must Match

Another significant requirement for using the new combined system is ensuring parish gross sales match state gross sales. If the totals gross sales do not reconcile, the system will not allow the filing. It should also be noted that return will be filed for each jurisdiction that is included on a taxpayer’s return, even if it is a zero return. To reconcile the parish sales to the state return, a taxpayer making sales in Cameron Parish (which does not levy a local sales tax) will need to report those sales on the combined return as Sales in Cameron Parish Domicile Code 1200.

Other Filing Methods Are Still Available (For Now)

While a taxpayer can still use LaTAP to file their state return, they will still have to enter their state information in the combined return and select a radio button indicating they are filing their state return on a different platform. The Sales Tax Online platform with also continue to be available but not all parishes use this system. Paper returns can also be filed in parishes that do not require electronic filing. The State Sales Tax Return for Consolidated Filers, the Hotel/Motel, Occupational License Tax, and Occupancy Tax Returns for some parishes that have them currently available in Parish E-File will remain available.

Amended Returns and Payments

Returns for periods prior to 2026 will remain available in Parish E-File and can be amended via Parish E-File. This allows taxpayers to address historical issues in the same platform and permits taxpayer access to historical account data.

Another improved feature is that taxpayers will be able to initiate all payments in a single workflow, which simplifies the mechanics for remittance. The submission of the payment has been simplified into one click of a button. Careful attention should be given to ensure no balances remain due on taxpayer accounts and that the amounts due by parish has been properly accounted for.

Data Import

For companies relying on importing their data, the ULSTB provided detailed data import instructions. This is a particularly high-risk area for larger taxpayers processing large amounts of data and adapting it to the required format, as formatting errors may lead to rejected filings or incomplete data uploads.

The link to the ULSTB instructions on importing data can be found here along with the rest of the new combined return instructions:

https://ULSTB.com/resources/online-sales-tax-filing-information

Practical Recommendations for Tax Departments and Takeaways

The availability of the Louisiana’s Combined Sales and Use Tax Return presents a valuable opportunity to streamline state and local sales and use tax reporting across all parishes. However, it is a new process and with new processes, come new challenges.

Taxpayers should log into the Parish E-File system well in advance of filing deadlines, confirm that filing frequencies are aligned across all parishes, and reconcile between state and local gross sales. If importing data, users should validate their data before live submission. Finally, any system issues should be carefully documented so that, if penalties arise, the company has a clear factual record to support potential abatement requests.

For additional information, please contact: Jaye Calhoun at (504) 293-5936, Willie Kolarik at (225) 382-3441, Divya Jeswant at (504) 293-5766, or Melania Smith at (713) 844-3068.

Jaye Calhoun, Willie Kolarik, Divya Jeswant, and Melania Smith are members of Kean Miller’s Tax group, which advises a variety of clients on federal, state and local tax (SALT), and estate planning matters. The team works collaboratively to develop practical, multidisciplinary strategies that anticipate issues, minimize risk, and resolve complex tax issues efficiently, whether through negotiations or formal litigation proceedings.