If you can’t file your 2025 Idaho income tax return by today’s (Wed) deadline, some Idahoans may be eligible to pay enough of the total tax due by today (Wed), and qualify for an automatic six-month extension.
To qualify, you need to pay one of the following:
80% of the estimated tax you owe for 2025, or 100% of the total tax reported on your 2024 income tax return (if you filed a return).
An automatic extension means you don’t have to send a written request. But an extension of time to file a return isn’t an extension of time to pay your tax. With a valid extension, you can avoid a penalty for filing late, but you’ll owe 6% annual interest on any tax you owe after April 15th until you pay it. In addition, a payment penalty will apply if you pay your taxes after you file your return, even if you have a filing extension.
To see if you qualify for an extension, complete the worksheet on Idaho Form 51, Estimated Payment of Individual Income Tax. The worksheet will help you figure out if you owe more tax beyond any payments you’ve made, or any amounts withheld from your paychecks or unemployment checks. You can find Form 51 online at tax.idaho.gov.
