Illinois Department of Revenue Urges Taxpayers to Act Now Ahead of April 15 Filing Deadline

SPRINGFIELD — With the April 15 deadline quickly approaching, the Illinois Department of Revenue (IDOR) is encouraging taxpayers to file their 2025 state individual income tax returns as soon as possible and avoid waiting until the last minute, especially if filing by mail.

“Filing electronically is still the fastest and most reliable way to get your return processed,” explained IDOR Director David Harris. “If you are expecting a refund, choosing direct deposit will help you receive it as quickly as possible. My Tax Illinois makes the process simple, guiding you step by step while helping to reduce errors.”

In addition to free filing of Form IL-1040 through My Tax Illinois, individuals may also utilize the site to make payments, respond to department inquiries, and check the status of refunds using the Where's My Refund? link. Taxpayers may also look up IL-PINs, amounts of any estimated tax payments made, and when necessary, amounts reported on Form 1099-G with MyTax Illinois. Taxpayers may choose to file using commercial tax preparation software, work with My Tax Illinois, a tax professional, or submit a paper Form IL 1040.

IDOR is also alerting taxpayers that recent changes announced by the United States Postal Service (USPS) could impact how tax filings are processed. Under updated USPS procedures, the postmark will reflect the date of the first automated processing operation rather than the date a piece of mail is dropped off at a local post office.

“Mailing your return at the last minute is a real risk this year,” Harris said. “Because of changes to USPS postmark procedures, the date on your envelope may not reflect when you dropped it off. Filing electronically or mailing well in advance of the deadline can help you avoid unnecessary penalties and give you peace of mind.”

Taxpayers who file electronically and submit an error free return can generally expect to receive their refunds via direct deposit in about four weeks. In 2025, IDOR received over 6.3 million IL 1040 returns, with more than 5.75 million, or 91.3 percent, filed electronically.

Taxpayers who cannot file their Illinois individual income tax return (Form IL-1040) by the April 15 deadline are automatically granted a six-month extension. For those who file on a calendar-year basis, the new due date is October 15, 2026.

Please note that an extension to file does not extend the time to pay. If taxes are owed, taxpayers must pay the amount due by April 15, 2026, to avoid penalties and interest. If taxpayers are unable to file a tax return and owe taxes, they may use Form IL-505-I, Automatic Extension Payment for Individuals.

For assistance, taxpayers can call IDOR at 1 800 732 8866 or 217 782 3336. Automated options are available for faster service, and free language assistance is offered for individuals with limited English proficiency. IDOR will also offer extended phone hours with live representatives available on Tuesday, April 14, from 8:00 a.m. to 7:00 p.m., and Wednesday, April 15, from 7:30 a.m. to 7:00 p.m.

For the most up to date information, forms, schedules, and instructions for the 2026 tax season visit tax.illinois.gov.

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