What Are Illinois Impact Fees?
Illinois authorizes county and municipal road improvement impact fees under 605 ILCS 5/5-901 et seq., while Chicago-area suburbs commonly require school and park land dedications or cash-in-lieu ('land-cash') contributions under 65 ILCS 5/11-12-5 and home-rule powers. Water and sewer tap-on fees round out the typical stack.
Collar-county suburbs (DuPage, Kane, Will, McHenry) carry the state's most structured fee programs; downstate costs are mostly utility-driven. Illinois figures on impactfees.org are model estimates for early comparison — school land-cash tables in particular change with land values, so verify locally.
Illinois figures are illustrative estimates from our statewide cost model — calibrated to local construction costs and community size — rather than verified fee schedules. Use them for early budgeting and site comparison, and see our methodology for how estimates are built.
Counties Covered
Our calculator covers all 102 Illinois counties:
Click any county to open the calculator pre-loaded with that jurisdiction.
Major Illinois Markets
Click any market to open the calculator pre-loaded with that city.
Chicago / Cook
Water/sewer charges and neighborhood-specific contributions dominate.
Naperville & Aurora / DuPage & Kane
Classic land-cash school and park fees plus road impact fees.
Joliet / Will
Will County growth corridor with road fees and utility tap-on charges.
Rockford / Winnebago
Utility connection charges lead; formal impact fees are limited.
Springfield / Sangamon
Downstate capital with municipal utility-driven one-time costs.
How the Calculator Works
- Pick your development type — Single-family, multifamily, commercial, industrial, or office.
- Search or pin your site — Enter an address or drop a pin anywhere in Illinois.
- We identify the jurisdiction — City, county, and state are resolved automatically.
- Get an instant breakdown — Water, sewer, road, park, school, and fire fees by category — verified where researched, clearly-labeled estimates where not.