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Illinois emissions test (Illinois Air Team): the official wording
Everything in quotation marks here is from 5 sources and was matched to them on November 11, 2026. The quotes are the sources’ words; ours only label them.
About these quotes.
The passage quoted from the statute’s definition of the affected counties stops before its full list of ZIP codes. The limits are in the statute.
On this page: where · how often · fee · new and older vehicles · diesel, electric, hybrid · check a vehicle · sources
What does the text call it?
For the status of Illinois Air Team emissions testing locations, please visit the Illinois Air Team website.
The page we point to: Illinois Air Team, home.
Which counties does the text name?
The quoted text names 10 counties. Some of the names come with limiting words in the quote (part of a county, an urban area, a boundary); the limit is in the quote and in the official source:
- Cook County
- DuPage County
- Lake County
- Kane County
- Kendall County
- Madison County
- McHenry County
- Monroe County
- Will County
- St. Clair County
"Inspection area" means Cook County, DuPage County, Lake County, and those portions of Kane, Kendall, Madison, McHenry, Monroe, Will, and St. Clair Counties included in the definition of "affected counties".
Excerpt: the definition goes on to list more ZIP codes
"Affected counties" means Cook County; DuPage County; Lake County; those parts of Kane County that are not included within any of the following ZIP code areas, as designated by the U.S. Postal Service on the effective date of this amendatory Act of the 94th General Assembly: 60109, 60119, 60135, 60140, 60142, 60144, 60147, 60151, 60152, 60178, 60182, 60511, 60520, 60545, and 60554
How often is the test?
Typically, even model-year vehicles are inspected during even years, and odd model-year vehicles are inspected in odd years.
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).
Shown with it, so that neither is read alone:
Vehicles need to be tested when they are four (4) years old. Even model-year vehicles are tested during even years and odd model-year vehicles are tested in odd years.
The inspection month coincides with the expiration date of the vehicle license plate.
What does the test cost?
Testing is free, whether at an existing high-capacity test station or at one of the new options (inspection and maintenance locations, self-service kiosk, MTU).
What does the text say about new and older vehicles?
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).
Shown with it, so that neither is read alone:
Vehicles need to be tested when they are four (4) years old. Even model-year vehicles are tested during even years and odd model-year vehicles are tested in odd years.
The following vehicles are not subject to emissions testing: Vehicles not subject to registration; Diesel-powered vehicles and vehicles that are powered exclusively by electricity; Motorcycles, motor-driven cycles and motorized pedal-cycles; Antique, expanded-use antique, and custom vehicles, street rods, and vehicles of model year 1967 or before
What about diesel, electric and hybrid vehicles?
Every current line we hold for Illinois that uses the word diesel, electric or hybrid. Some are about one place or one kind of test; each speaks for itself.
The following vehicles are not subject to emissions testing: Vehicles not subject to registration; Diesel-powered vehicles and vehicles that are powered exclusively by electricity; Motorcycles, motor-driven cycles and motorized pedal-cycles; Antique, expanded-use antique, and custom vehicles, street rods, and vehicles of model year 1967 or before
An On-Board Diagnostics (OBD) test is used for 1996 and newer passenger cars and light-duty trucks (including vans, sport utility vehicles and hybrids).
What about heavier vehicles?
Listed under:
The following vehicles are not subject to emissions testing:
Vehicles of model year 2006 or earlier with a manufacturer gross vehicle weight rating between 8,501 and 14,000 pounds; and Vehicles with a manufacturer gross vehicle weight rating greater than 14,000 pounds.
What else does the text say?
The goal of the Illinois Vehicle Emissions Testing Program is to improve air quality and public health.
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.
Vehicle emissions testing is required on all 2007 or newer heavy-duty vehicles with a manufacturer's gross vehicle weight rating (GVWR) between 8,501 and 14,000 pounds.
In certain cases, a vehicle may need to be inspected if it was not in compliance when acquired by a new owner, or when the vehicle is newly registered in a test area.
For a $20 fee, gasoline-powered vehicles that would be testable in the Illinois program may receive a voluntary emissions test.
Check a vehicle against these quotes
Enter a model year, a fuel and a weight rating, and choose the county. The checker repeats the quotes above and, where a figure can be compared, says where your entry falls against it. It does not decide anything about your vehicle.
Where do these quotes come from?
- Illinois EPA, Vehicle Emissions Testing Program (epa.illinois.gov; state agency page; read November 11, 2026)
- Illinois EPA, Vehicle Emission Test Program frequently asked questions (epa.illinois.gov; state agency page; read November 11, 2026)
- 625 ILCS 5/13C-5, Definitions (Illinois Vehicle Code) (ilga.gov; statute or administrative code; read November 11, 2026)
- Illinois Air Team, home (ilairteam.com; program site we treat as contractor-run, linked from Illinois EPA, Vehicle Emissions Testing Program; read November 11, 2026)
- Illinois Air Team, Motorist FAQs (ilairteam.com; program site we treat as contractor-run, linked from Illinois EPA, Vehicle Emissions Testing Program; read November 11, 2026)
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