How to File an Amended Montana Tax Return

Instructions, Resources on how to prepare and e-File Montana Tax Returns or how to prepare an Extension and/or previous Year Tax Returns

Prepare, eFile a 2023 tax year MT + IRS Tax Return: Detailed eFile.com Service Overview

Prepare only a MT State Return without an IRS return. Details

Step by Step instructions on how to only Prepare and Download - not eFile - State Returns on eFile.com.

File a 2023 tax year Montana Tax Amendment

You cannot eFile a MT Tax Amendment anywhere, except mail it in. However, you can prepare it here on eFile.com.
Option 1: Sign into your eFile.com account, modify your Return and download/print the MT Form 2 under My Account.Check the "Mark if this is an amended return." box, sign the form, and mail it to one of the addresses below. When sending the tax amendment form make sure to attach any schedules and other documents that were used when making the original filing.
Option 2: If you don't have an eFile.com account follow the step by step instruction on how to prepare a tax return/amendment.
Option 3: If you want to do the math on your own paper return then complete, sign MT Form 2 - Print, Mail the Form to MT Tax Department to:
Tax Refund or No Payment Tax Amendment
Montana Department of Revenue
P O Box 6577
Helena, MT 59604-6577
Tax Payment Tax Amendment
Montana Department of Revenue
P O Box 6308
Helena, MT 59604-6308

MT Tax Amendment Form 2
This Form can be used to file a: Tax Return, Tax Amendment, Change of Address. Check the "Mark if this is an amended return." box

Step 1: Download, Complete Form 2 for the appropriate Tax Year below.
Step 2: Sign, Mail Your Amended Return to one of the addresses listed above. When sending the tax amendment form make sure to attach any schedules and other documents that were used when making the original filing.

2023 tax year only: Prepare online on eFile.com the October deadline. When done Print, Sign and Mail in - not eFile - Your Tax Amendment, Address Change, etc.

After the October deadline, Prepare, Print, Sign and Mail-In - see address above - your Form 2.

How to correct a rejected Tax Return

If your MT Tax Return was rejected by the MT Tax Agency - not eFile.com - instructions on how to correct a rejected Montana Tax Return.

For all Tax Years prior to 2023 tax year Prepare, Print, Sign and Mail-In - see address above - your Tax Amendment as soon as possible. Select the Form 2 for the Tax Year you are amending. When sending the tax amendment form make sure to attach any schedules and other documents that were used when making the original filing. You will also file an IRS Tax Amendment Form 1040X.

Check Your MT Tax Amendment Status

1. Call the MT Department of Revenue at 1 (866) 859-2254.
2. Contact the MT Department of Revenue

Montana Refund Deadlines

A. Three years from the due date of the original tax year return, including valid filing extensions.
B. One year from the final determination of the amended federal return or federal change, whichever is later, provided that the allowable refund is not more than the decrease in Montana tax attributable to the federal change or correction.
C. Two years from the payment of an assessment, provided the amended return raises issues relating only to the prior assessment and the refund does not exceed the amount of tax paid on the prior assessment.
D. Two years from the filing of an amended Montana return resulting in the payment of additional tax, provided that the current amended return raises issues relating solely to the prior amended return and that the refund does not exceed the amount of the tax payment made as a result of the prior amended return.
Additional Montana Tax Income Taxes Deadlines

Montana Income Tax Penalties

Find out how Montana Late Filing and Late Payment Penalties are calculated.
For IRS Tax and Late Filing Penalties we have an easy to use tool: The PENALTYucator.

File an IRS Tax Amendment by Tax Year

Instructions on how to prepare an IRS Tax Amendment on eFile.com, however the IRS does not accept Tax Amendments electronically.