Indiana Business State Tax Extension I LLCs / Partnership Filing Guide

Modified on Thu, 11 Jun at 1:20 PM

Indiana Business State Tax Extension I LLCs / Partnership Filing Guide

Overview

Indiana LLCs and partnerships are subject to state tax filing requirements, administered by the Indiana Department of Revenue. Indiana grants an automatic extension tied to an approved IRS extension, making the process simple for businesses that have already filed IRS Form 7004.

Original Filing Deadline

The original due date for the Indiana LLCs / Partnerships return is March 16, 2026. File or remit full payment by this date to remain in good standing.

Extension Period & Extended Deadline

Indiana automatically grants an extension to file, provided you have obtained an approved federal extension from the IRS by filing IRS Form 7004. With a valid IRS extension, the Indiana extended deadline becomes September 15, 2026. No separate state extension form is required—the federal extension serves as your Indiana extension.

Payment Is Still Due by Original Deadline

The extension applies to filing only—it is not an extension to pay taxes owed. Any outstanding tax liability must be paid by the original due date of March 16, 2026 to avoid penalties and interest. Use the Indiana | Online Tax Extension Payment to pay electronically. For mail-in payments, use Form E-6 | Request for Indiana Corporate Estimated Quarterly Income Tax Returns (Form IT-6) and send to:
Indiana Department of Revenue Corporate Tax Division P.O. Box 7228 Indianapolis, IN 46207-7228

Late Filing and Payment Penalties

Failure to File: 10% penalty of amount of tax due.
Failure to Pay: 10% penalty of amount held in trust.

Best Practices

Estimate and pay your Indiana business tax by March 16, 2026 to avoid interest and penalties.
File IRS Form 7004 with the IRS to secure your federal extension, which Indiana automatically honors.
Use the state online payment portal for fast, convenient electronic payment.
Set a reminder to file your completed Indiana LLCs / Partnerships return by September 15, 2026.

Final Thoughts

Indiana’s business tax extension is straightforward once your federal extension is approved. Pay 100% of any tax due by March 16, 2026 and file your LLCs / Partnerships return by September 15, 2026.

Quick Reference Table

State Abbreviation	IN
State Name	Indiana
Business Entity Type	LLCs / Partnerships
Extension Status	Approved with Federal Extension
Return Due Date	March 16, 2026
Extended Due Date	September 15, 2026
Other Information	Indiana grants your business an automatic 6-month extension provided you have obtained an approved IRS extension. The extension is NOT an extension to pay any taxes you may have due. Tax payments are due by the original return due date. Federal extension form must be attached to return and extension box must be checked on front page of return.
Online Payment	Indiana \| Online Tax Extension Payment
Payment Voucher Form	Form E-6 \| Request for Indiana Corporate Estimated Quarterly Income Tax Returns (Form IT-6)
State Payment Agency	Indiana Department of Revenue
Mailing Address with Payment	Indiana Department of Revenue Corporate Tax Division P.O. Box 7228 Indianapolis, IN 46207-7228
Failure to File Penalties	10% penalty of amount of tax due.
Failure to Pay Penalties	10% penalty of amount held in trust.