With the April 15th deadline nearing, the Illinois Department of Revenue (IDOR) is urging taxpayers to file their 2025 state income tax returns as soon as possible, especially if mailing paper forms. IDOR Director David Harris recommends filing electronically through My Tax Illinois for the fastest, most accurate processing and quickest refunds via direct deposit.
Recent changes by the United States Postal Service mean that postmarks now reflect the date of the first automated processing, not when mail is dropped off. As a result, last-minute mailing could lead to late filings and penalties.
Taxpayers who file electronically and submit error-free returns can expect refunds within about four weeks. Those unable to file by April 15th are granted an automatic six-month extension, but any taxes owed must still be paid by the deadline to avoid penalties and interest.
For assistance, contact IDOR at 1-800-732-8866 or 217-782-3336. Extended phone hours will be available April 14th and 15th. For forms and the latest updates, visit tax.illinois.gov.