How Do I Amend an Idaho State Return?

If your Idaho return has already been accepted and you need to make changes, you'll need to file an amended Idaho return.

Common reasons for amending a return include:

• Correcting income
• Adding or removing deductions or credits
• Updating filing status
• Reporting additional tax documents
• Correcting withholding or estimated payments

Idaho amended returns must be completed after the original return has been accepted.

How to Generate an Amended Idaho Return

To create your amended Idaho return, follow these steps:

1. Select 2026 Amended Return from the navigation bar.
2. Pay for the amended return.
3. Review the Filing an Amended Return page and select Continue.
4. Select Amend State Return(s) and choose Begin.
5. Select + Amend State from inside the white box.
6. Scroll to the bottom of the Idaho return menu and select Amended Return.
7. Choose a reason from the Reason for Amended Return dropdown menu.
8. Complete all applicable sections and make the necessary corrections.

What If I Received a Refund From My Original Idaho Return?

If you received a refund from Idaho on your original return, you must report that refund on the amended return so the program can correctly calculate your revised balance due or refund.

After navigating to the Amended Return section:

• Enter the amount you received in the field labeled Refund from Original plus any additional refunds received.

What If I Originally Owed Taxes?

If you paid Idaho tax with your original return, that payment must also be entered on the amended return.

After navigating to the Amended Return section:

• Enter the amount paid in the field labeled Tax Paid with Original plus any additional tax paid.

This ensures the program properly credits payments already made when calculating the amended return.

How Do I File My Amended Idaho Return?

Idaho amended returns must be paper filed.

To print the amended return:

1. Select Summary/Print from the navigation bar.
2. Select View Return from the Tax Return Summary page.
3. Open the generated PDF.
4. Print and sign the amended Idaho return.
5. Mail the amended return to the appropriate Idaho mailing address.

What Should I Mail?

Generally, mail:

• The amended Idaho return only
• Copies of any supporting documents related to the change (such as Forms W-2, 1099, schedules, or other supporting forms)

Don't mail a copy of the originally filed return unless Idaho specifically requests it.

It's also a good idea to compare your original and amended PDF copies before mailing the return to verify the changes made.

Where Do I Mail the Amended Return?

The mailing address is printed on the amended return.

Keep in mind:

• The mailing address may differ depending on whether you're receiving a refund or including a payment.
• You can also verify the correct address on the Idaho State Tax Commission website before mailing.

Explanation Required

When filing an amended Idaho return, you must provide an explanation of what changed.

Be sure to complete the explanation section and clearly describe:

• What information was changed
• Why the change is needed
• Any documents supporting the correction

Providing a complete explanation helps Idaho process the amended return more quickly.