What to Know About Illinois Emissions Testing

Illinois emissions testing is required for most gasoline-powered vehicles in counties located near big cities every two years. But some exceptions may apply, depending on your ZIP code.

Sarah Archambault
Sarah Archambault
  • Experienced personal finance writer

  • Background working with banks and insurance companies

Sarah enjoys helping people find smarter ways to spend their money. She covers auto financing, banking, credit cards, credit health, insurance, and personal loans.

Featured in

media logomedia logo
Ashley Cox
Edited byAshley Cox
Headshot of Managing Editor Ashley Cox
Ashley CoxSenior Managing Editor
  • 7+ years in content creation and management

  • 5+ years in insurance and personal finance content

Ashley is a seasoned personal finance editor who’s produced a variety of digital content, including insurance, credit cards, mortgages, and consumer lending products.

Featured in

media logomedia logomedia logomedia logo

Updated October 4, 2024

Advertiser Disclosure

At Insurify, our goal is to help customers compare insurance products and find the best policy for them. We strive to provide open, honest, and unbiased information about the insurance products and services we review. Our hard-working team of data analysts, insurance experts, insurance agents, editors and writers, has put in thousands of hours of research to create the content found on our site.

We do receive compensation when a sale or referral occurs from many of the insurance providers and marketing partners on our site. That may impact which products we display and where they appear on our site. But it does not influence our meticulously researched editorial content, what we write about, or any reviews or recommendations we may make. We do not guarantee favorable reviews or any coverage at all in exchange for compensation.

Why you can trust Insurify: Comparing accurate insurance quotes should never put you at risk of spam. We earn an agent commission only if you buy a policy based on our quotes. Our editorial team follows a rigorous set of editorial standards and operates independently from our insurance partners. Learn more.

The Illinois Environmental Protection Agency requires emissions testing to help improve air quality and public health — especially in urban areas, like Chicago, where reducing air pollution from motor vehicles is a top priority. Drivers living in the state of Illinois may need to complete emissions testing on their vehicles periodically.

Most cars made after 1996 require emissions testing if they’re 4 or more years old and if the car owner lives in a certain county, including those that surround Chicago and border St. Louis.[1] Some people and vehicles are exempt from these rules, but most drivers will need to comply with these testing requirements.

Here’s what you need to know about Illinois emissions testing requirements.

How emissions testing works in Illinois

While not all states require regular emissions or smog testing, Illinois state law does require it.[2] In 1990, the Clean Air Act required the Environmental Protection Agency (EPA) to set certain National Ambient Air Quality Standards (NAAQS) to help protect the environment and public health. The EPA advises emissions testing to help improve air quality.[3]

Because the air in certain parts of Illinois exceeds the ozone NAAQS, drivers in some areas of this state must comply with regular emissions testing. Due to the Illinois Vehicle Emissions Inspection Law of 2005, drivers living in a county or ZIP code with air pollution issues must complete emissions testing if their car is more than 4 years old and was built after 1996. This inspection typically occurs when the vehicle’s license plate expires.

During emissions tests in Illinois, most cars will undergo an on-board diagnostics (OBD) test, which involves using a scanning tool to monitor a car’s on-board computer. This tool checks the OBD system status through a readiness check and identifies whether the malfunction indicator lamp/light is on. The scanning tool can also retrieve any stored diagnostic trouble codes.[4]

The car will likely pass the OBD test if the OBD system works.

Find Cheap Car Insurance in Illinois

Liability rates start as low as $30 per month

Secure. Free. Easy-to-use.
Based on 3,806+ reviews
4.8/5
Shopper Approved
ProgressiveLiberty MutualAllstate

Illinois emissions testing requirements

If an Illinois car manufactured after 1996 qualifies for regular emissions testing, the owner must complete an emissions test every two years once the car reaches 4 years old. If a car fails an emissions inspection, the owner will need to have it retested after completing any necessary repairs. Cars that require emissions testing must complete testing to renew registration.

Counties that require emissions testing

Only people who live in counties near large cities, like Chicago and outside of St. Louis, are required by law to pass an emissions test. Illinois emissions testing is generally required every two years if you live in Cook, Lake, or Dupage counties. Exclusions may apply in other counties, depending on your ZIP code.

You may have to undergo testing if you live in one of the following Illinois counties:

  • Cook

  • Dupage

  • Kane

  • Kendall

  • Lake

  • Madison

  • McHenry

  • Monroe

  • St. Clair

  • Will

Failure to get an emissions test on time can result in fines ranging from $50 to $300 or more. If you’re not sure if your vehicle needs to be tested, confirm your vehicle’s status online using the state’s Vehicle Eligibility Check tool.

Vehicles that must complete emissions testing

The majority of gasoline-powered vehicles built during 1996 or later require testing if they’re 4 years or older. Here’s a closer look at the types of vehicles that typically need emissions tests:[5]

  • Passenger cars

  • Light-duty trucks, including SUVs and vans

  • Heavy-duty vehicles 2007 model year and newer with a gross vehicle weight rating (GVWR) between 8,501 and 14,000

Vehicles exempt from emissions testing

Not all types of vehicles require Illinois emissions testing. Vehicles exempt from emissions testing include the following:[6]

  • Vehicles that don’t require registration

  • Diesel-powered vehicles

  • Electric vehicles (but not hybrids)

  • Cars built in 1967 or before

  • Antique vehicles

  • Custom vehicles

  • Street rods

  • Custom vehicles

  • Motorcycles

  • Farm and husbandry vehicles

  • Vehicles registered in another state that remain compliant with that state’s emissions laws

  • Vehicles with a junking certificate

  • Government-owned war vehicles

  • 2006 and earlier vehicles with a GVWR between 8,501 and 14,000 pounds

  • Vehicles with a GVWR higher than 14,000 pounds

How to complete emissions testing in Illinois

You’ll need to take the following steps to complete emissions testing in Illinois:

  • Prepare for an emissions test. To avoid failing an emissions test, first confirm that your check engine light is off and that the OBD system is operating. Also confirm that your car’s diagnostic link connector isn’t damaged, inaccessible, or missing before you take your vehicle to an Illinois vehicle emissions testing center.

  • Find a testing center. To find Illinois emissions test locations, use the Illinois Air Team Testing Station Locator. Warm your vehicle up by driving it for at least 15 minutes before arriving for your test.

  • Complete the inspection. Emissions testing usually lasts between 15 and 40 minutes. Costs vary for this test, but it typically costs around $20.

Shop for Illinois Car Insurance

Check quotes from 100+ top insurance companies

Secure. Free. Easy-to-use.
Based on 3,806+ reviews
4.8/5
Shopper Approved
ProgressiveLiberty MutualAllstate

What to do if you fail emissions testing

Your vehicle may fail inspection if certain emissions systems aren’t functioning properly or as a result of wear and tear that causes gasoline vapors or other pollutants to escape into the environment. Keeping up with regular maintenance, such as replacing your spark plugs, can help avoid issues that may cause emissions testing failure.

If your car fails an emissions test, you can still drive it, but you need to repair the issue that caused the failure before retesting. After a failed test, you’ll receive the following documents to help you and a repair technician determine how to make the necessary repairs:

  • Vehicle inspection report (VIR) with test result details

  • Repair shop report (RSR) with a snapshot with a list of nearby repair facilities

  • Repair data form (RDF) to be completed by a repair technician

The Illinois EPA recommends having repairs made by an expert technician trained in emissions diagnosis and repair. And after having your car repaired, the repair tech must complete and submit the RDF, or you can bring it with you when you return to the inspection facility for a recheck.

In some cases, you may qualify for a repair waiver. Common reasons include failure to pass after at least two tests, completion of a minimum of $1,111 in emissions-related repairs, or when all emissions control devices appear to be functioning properly.

Illinois emissions testing FAQs

Find answers to some commonly asked questions about Illinois emissions testing below.

  • What do you do if you lose your emissions test notice?

    If you lose your emissions test notice, you can check the current status of your car’s testing requirements through the Illinois Title and Registration Status Inquiry.

  • Who is exempt from emissions testing in Illinois?

    Vehicles of a certain type, built before select years, or that belong to drivers in certain counties can be exempt from emissions testing in Illinois. Most gasoline-powered passenger vehicles of model year 1996 or newer in these counties must undergo emissions testing: Cook, Dupage, Kane, Kendall, Lake, Madison, McHenry, Monroe, St. Clair, and Will. But vehicles in certain ZIP codes may be exempt.

  • How do you prepare your vehicle for emissions testing in Illinois?

    To prepare your car to pass an emissions test in Illinois, check on a few vehicle elements first. Confirm that your check engine light is off, that the OBD system is operating, and that your car’s diagnostic link connector is present, undamaged, and accessible before you attend the test.

  • Does Illinois require emissions testing?

    The state of Illinois requires certain vehicles in select counties to undergo emissions testing to help improve air quality and public health. Not all states require emissions testing.

  • Can you pass a vehicle emissions test with a check engine light on?

    No, you can’t pass a vehicle emissions test with a check engine light on. Having this light on is one of the main reasons cars fail this test. Before you take your car to an Illinois emissions test facility, confirm the check engine light is off.

Sources

  1. Illinois Environmental Protection Agency. "Vehicle Emissions Testing Program."
  2. Emissions.org. "Smog Check – Vehicle Emissions Tests."
  3. United States Environmental Protection Agency. "NAAQS Table."
  4. Illinois Air Team. " About Vehicle Emissions Testing."
  5. Illinois Air Team. "Does My Vehicle Need to be Tested?."
  6. DMV.org. "Car Inspection in Illinois."
Sarah Archambault
Sarah Archambault

Sarah Archambault enjoys helping people figure out how to manage their finances and credit. She covers auto financing, banking, credit cards, credit health, insurance, and personal loans. Her work has been featured on Credit Karma, Experian, LendingClub, Sound Dollar and USA Today Blueprint. She also writes for national insurers, banks and financial institutions like Aetna, MassMutual, Stripe, and UnitedHealthcare. 

Ashley Cox
Edited byAshley CoxSenior Managing Editor
Headshot of Managing Editor Ashley Cox
Ashley CoxSenior Managing Editor
  • 7+ years in content creation and management

  • 5+ years in insurance and personal finance content

Ashley is a seasoned personal finance editor who’s produced a variety of digital content, including insurance, credit cards, mortgages, and consumer lending products.

Featured in

media logomedia logomedia logomedia logo

Compare Car Insurance Quotes Instantly

Secure. Free. Easy-to-use.
Based on 3,806+ reviews
4.8/5
Shopper Approved
ProgressiveLiberty MutualAllstate

Latest Articles

View all