Louisiana Business Tax Deadlines (2026)
Next: June 15, 2026 — Federal & Louisiana Q2 Estimated Tax Payment
Next Deadline: June 15, 2026 — Federal & Louisiana Q2 Estimated Tax Payment
Federal Tax Deadlines (2026)
| Form | Who Files | Due Date | Extension Deadline |
|---|---|---|---|
| Form 1040 (Schedule C) | Sole proprietors | April 15 | October 15 |
| Form 1065 | Partnerships, Multi-member LLCs | March 15 | September 15 |
| Form 1120-S | S-Corporations | March 15 | September 15 |
| Form 1120 | C-Corporations | April 15 | October 15 |
| Form 990 | Nonprofits | May 15 | November 15 |
| Estimated Taxes (Q1) | All | April 15 | — |
| Estimated Taxes (Q2) | All | June 15 | — |
| Estimated Taxes (Q3) | All | September 15 | — |
| Estimated Taxes (Q4) | All | January 15, 2027 | — |
Louisiana State Tax Deadlines (2026)
| Tax Type | Due Date | Form/Filing | Notes |
|---|---|---|---|
| Individual Income Tax | May 15 | Form IT-540 | Flat 3% rate; due May 15 |
| Corporate Income Tax | May 15 | Form CIFT-620 | Flat 5.5% rate |
| Corporate Franchise Tax | May 15 | Filed with CIFT-620 | $2.75 per $1,000 of taxable capital (being phased out) |
| S-Corp Return | March 15 | Form CIFT-620 | Pass-through |
| Partnership Return | March 15 | Form IT-565 | Pass-through |
| Sales Tax (Monthly) | 20th of following month | Via Louisiana File Online | State rate 4.45% |
| Withholding Tax (Monthly/Quarterly) | Varies by payroll | Form L-1 | Employers |
| Annual Report | Anniversary of formation | Filed with Secretary of State | $30 (LLC); $75 (Corp) |
| Estimated Income Tax (Q1) | April 15 | Form IT-540ES / CIFT-620ES | — |
| Estimated Income Tax (Q2) | June 15 | Form IT-540ES / CIFT-620ES | — |
| Estimated Income Tax (Q3) | September 15 | Form IT-540ES / CIFT-620ES | — |
| Estimated Income Tax (Q4) | January 15, 2027 | Form IT-540ES / CIFT-620ES | — |
Quarterly Estimated Tax Deadlines in Louisiana
Louisiana follows the federal estimated tax payment schedule for quarterly payments, even though the annual return is due May 15:
Estimated payments are required if you expect to owe $1,000 or more in Louisiana income tax.
Louisiana-Specific Tax Requirements
Louisiana recently underwent major tax reform. The individual income tax is now a flat 3% rate (down from the previous graduated system), and the corporate income tax is a flat 5.5%. Louisiana also imposes a corporate franchise tax of $2.75 per $1,000 of taxable capital employed in the state, but this tax is being phased out over several years. The individual income tax return is due May 15 (one month after the federal deadline), giving filers extra time.
Louisiana's state sales tax rate is 4.45%, but combined with local parish (county) taxes, total rates can exceed 12% in some areas — among the highest combined rates in the nation. Louisiana's local sales tax system is notoriously complex, with multiple local taxing jurisdictions. The state created the Louisiana Sales and Use Tax Commission for Remote Sellers to handle remote seller compliance. The economic nexus threshold is $100,000 in sales or 200 transactions.
Employers must register for withholding tax and file returns on a schedule based on payroll amounts. Annual reports are filed with the Louisiana Secretary of State on the anniversary of the entity's formation. Louisiana has a robust tax incentive program, particularly for the film, tech, and energy industries.
What Happens If You Miss a Louisiana Tax Deadline?
Louisiana Department of Revenue
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