Illinois
For Illinois, counties where testing is required is these areas of Illinois; program / authority is vehicle emissions inspection program, verified against its source on 2026-08-18.
- State
- Illinois our reading
- Counties where testing is required
- these areas of Illinois verified
- Program / authority
- vehicle emissions inspection program verified
- How often
- even model-year vehicles are inspected during even years, and odd model-year vehicles are inspected in odd years per epa.illinois.gov
- Vehicles covered / exempt
- Most 1996 and newer gasoline-powered passenger vehicles are subject to emissions inspections after they are four years old per epa.illinois.gov
Values marked our reading are our classification of what the source says — the source does not print them in those words. The quote below is the evidence for each one; judge it yourself.
What the source says
Additionally, the Illinois Vehicle Emissions Inspection Law of 2005 (625 ILCS 5/13C) requires a vehicle emissions inspection program to reduce air pollution from motor vehicles in these areas of Illinois. For these reasons, the vehicle emissions inspection program is part of Illinois EPA’s strategy to reduce air pollution in Illinois and bring the Chicago and Metro-East areas into attainment of the ozone NAAQS.
— epa.illinois.gov, retrieved 2026-08-18
What epa.illinois.gov says
Most 1996 and newer gasoline-powered passenger vehicles are subject to emissions inspections after they are four years old (e.g. 2012 vehicles are being inspected in 2016 for the first time). The inspection month coincides with the expiration date of the vehicle license plate. Typically, even model-year vehicles are inspected during even years, and odd model-year vehicles are inspected in odd years.
— epa.illinois.gov, retrieved 2026-08-18
Source
- epa.illinois.govhttps://epa.illinois.gov/topics/air-quality/mobile-sources/vehicle-emissions-testing.html