Indiana Business State Tax Extension I Fiduciaries Filing Guide

Modified on Thu, 11 Jun at 1:20 PM

Indiana Business State Tax Extension I Fiduciaries Filing Guide

Overview

Indiana fiduciaries—including estates and trusts—are subject to state fiduciary income tax 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 8868.

Original Filing Deadline

The original due date for the Indiana Fiduciaries return is April 15, 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 8868. With a valid IRS extension, the Indiana extended deadline becomes October 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 April 15, 2026 to avoid penalties and interest. Use the Indiana | Online Tax Extension Payment to pay electronically. For mail-in payments, use Form IT-41ES | Fiduciary Payment Voucher Estimated Tax, Extension, or Composite Payment 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 April 15, 2026 to avoid interest and penalties.
File IRS Form 8868 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 Fiduciaries return by October 15, 2026.

Final Thoughts

Indiana’s business tax extension is straightforward once your federal extension is approved. Pay 100% of any tax due by April 15, 2026 and file your Fiduciaries return by October 15, 2026.

Quick Reference Table

State Abbreviation	IN
State Name	Indiana
Business Entity Type	Fiduciaries
Extension Status	Approved with Federal
Return Due Date	April 15, 2026
Extended Due Date	October 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 IT-41ES \| Fiduciary Payment Voucher Estimated Tax, Extension, or Composite Payment
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.