State Preemption of Local Zoning in Illinois
How Illinois state law overrides local zoning ordinances. ADU preemption, lot split preemption, and impact on city-level regulations.
Official Source Could Not Be Reached
The official government source for this jurisdiction could not be reached to confirm or deny a statewide preemption statute. Regulation is local until otherwise confirmed.
What Is State Preemption?
State preemption occurs when a state law overrides local government ordinances in a specific area. In land use, preemption means a city or county cannot adopt zoning rules that are more restrictive than the state standard. If a city tries to prohibit something the state law permits, the state law wins.
Illinois has limited preemption in housing law. Local governments generally have broad authority to regulate land use within their jurisdictions, subject to state constitutional and statutory limits.
Compare all 51 jurisdictions: ADU preemption table · Short-term rental preemption table
How Preemption Affects Illinois Cities
State preemption applies to every incorporated city and unincorporated area in Illinois. Select a city below to see how state preemption interacts with local zoning rules.
Source: Illinois State Law. Last verified April 3, 2026. View source