The Illinois Department of Revenue (IDOR) is the tax collection agency for the State of Illinois and also administers a number of taxes imposed by local governments. The $67.6 billion collected by the department in FY 23 accounts for virtually all of Illinois' own source revenue and is used to provide public safety, health, educational and human services to Illinois citizens. IDOR also has oversight responsibilities involving the nearly $33.8 billion local property tax system.
IDOR's operations are divided into six primary areas: Account Processing, Taxpayer Services, Tax Enforcement and Collections, Audit Bureau, Legal Services, and Administrative Services. The taxes collected come from three key sources: (1) Illinois Income Tax; (2) Retailers' Occupation Tax and Use Tax (commonly referred to as sales tax); and (3) excise taxes, including taxes on liquor, cigarettes, public utilities, hotel occupancy, and motor fuel. The department's central office is located in Springfield, with five additional regional offices, including an office location in downtown Chicago.
IDOR processes approximately 6.2 million individual income tax returns and 2.1 million business income tax and withholding income tax returns annually. Approximately 66% filing individual income tax returns for the 2022 filing period filed in 2023 received refunds. An estimated 91% of all individual income tax returns are now filed electronically.
Along with its state and local tax collection responsibilities, the department has general oversight responsibilities for Illinois local governments' property tax system. IDOR issues county equalization factors to assure uniform property assessment levels throughout the state and assists local assessing officials with their property tax responsibilities.
IDOR has approximately 1,300 employees in its overall operation.
Agencies
Services