The Illinois Department of Revenue announced Tuesday it will begin accepting income tax returns on January 26, making the official start to the 2026 filing season.
The Internal Revenue Service will open the federal filing season on the same date, the department recently announced.
“We want the tax filing process to be as smooth and stress-free as possible” said IDOR Director David Harris. “Before filing, you should make sure you have all income documents, such as W-2s and 1099s. Filing online, reviewing information carefully, and submitting your returns early can help avoid delays and get you any refunds you may be entitled to sooner.”
IDOR is encouraging taxpayers to file electronically and choose direct deposit to receive refunds as quickly and securely as possible.
Those who opt for direct deposit should receive their refunds in approximately four weeks, the department said.
During the 2025 filing season, the IDOR received over 6.3 million individual income tax returns. Of those, 91.3% were filed electronically, the department said.
IDOR also noted changes to United States Postal Service rules for postmarks could impact tax filings in 2026.
The USPS postmark now shows the date of the first automated processing operation instead of when the mail was dropped off, though USPS will continue to add manual postmarks upon request at their offices, IDOR explained.
“If you plan to mail your return or payment, don’t wait until the last day,” Harris stressed. “Sending it early or requesting a manual postmark at the post office can help protect you from late penalties.”
Other changes for the 2026 tax season come from the IRS will be implementing major provisions of Republicans’ tax and spending package, also known as the “One Big Beautiful Bill Act,” signed into law last summer. According to the IRS, the act will “significantly affects federal taxes, credits and deductions.”
A closer look at the changes can be found here.
Illinois taxpayers can use IDOR’s free online filing option called MyTax Illinois. The website guides users through the filing process, performing calculations automatically and reducing errors, IDOR said.
