Contact the Illinois Department of Revenue by dialing 1-800-732-8866 or 1-217-782-3336, according to the official website of the Illinois Department of Revenue. The department also maintains a business hotline for businesses and tax professionals at 1-217-524-4772. Alternatively, walk in to one of the department’s local offices for assistance in person.
The Illinois Department of Revenue offers assistance to taxpayers via phone Monday through Friday from 8 a.m. to 5 p.m., advises the department's website. It also offers a TDD line for hearing-impaired taxpayers at 1-800-544-5304. Taxpayers may send general correspondence or mail tax forms without payments to the Illinois Department of Revenue, Springfield, IL, 62719-0001. The department publishes a complete list of its contact information on its website, accessible by clicking on the Contact Us link on the side bar.