Should I file an Idaho Extension?
If you can't file your Idaho state income taxes by April 15, 2026, you're eligible to get an automatic six-month filing extension as long as you pay either an estimated 80% of your current year's tax liability or 100% of what you paid for state income taxes the prior year. Complete the worksheet on Idaho Form 51: Estimated Payment of Individual Income Tax to see if you meet the extension requirements and to determine if any payments are required.
If you need to make a payment, you'll need to mail Form 51 to the Idaho State Tax Commission with a check or money order by April 15, 2026.
If you qualify for an extension to file your Idaho return, you must file your return and any make any remaining payments by October 15, 2026.
You can set up your extension payment here: Menu Path: Account > File an Extension. We'll fill out a payment voucher for you, which you can mail to the Idaho State Tax Commission by the original due date for filing the return to avoid penalties and interest.
If you're expecting an Idaho refund, you don't need to do anything. You have an automatic extension and you can file when you're ready.
If you need to make a payment, you'll need to mail Form 51 to the Idaho State Tax Commission with a check or money order by April 15, 2026.
If you qualify for an extension to file your Idaho return, you must file your return and any make any remaining payments by October 15, 2026.
You can set up your extension payment here: Menu Path: Account > File an Extension. We'll fill out a payment voucher for you, which you can mail to the Idaho State Tax Commission by the original due date for filing the return to avoid penalties and interest.
If you're expecting an Idaho refund, you don't need to do anything. You have an automatic extension and you can file when you're ready.
