What you need to know about Chicago's emissions test requirement

Chicago requires an emissions test every two years for most vehicles registered in the city. The test checks whether your car's exhaust meets state pollution standards. You can take the test at any of the state-certified testing stations around Chicago — you do not have to go to a specific location or make an appointment in advance at most facilities.

The test itself takes about 10 to 15 minutes and costs between $15 and $30, depending on the testing station. You will need your vehicle registration and a valid ID. If your car fails, you have 30 days to fix the problem and retest at no additional charge.

Key Takeaways

  • Chicago emissions tests are required every two years and must be completed before your registration expires.
  • You can visit any state-certified testing station in the Chicago area without an appointment at most locations.
  • The test costs $15 to $30 and takes 10 to 15 minutes, and you will need your registration and ID.
  • If you fail, you have 30 days to repair your vehicle and retest for free at the same station.
  • You cannot renew your vehicle registration until you pass the emissions test.

Finding a testing station in Chicago

The Illinois Environmental Protection Agency maintains a list of certified emissions testing stations on its website. You can search by ZIP code to find stations near you. Most stations are open during regular business hours, and many stay open into the evening or operate on Saturdays.

Call ahead if you want to confirm hours or ask whether they accept walk-ins. Some stations do take appointments, which can save you time during busy periods. A few stations may have longer wait times during peak months (typically before registration renewal important date), so going early in the day or mid-week often means shorter lines.

What happens during the test

When you arrive, bring your vehicle registration and a valid ID. The technician will connect your car to a machine that reads emissions data from your vehicle's onboard computer. For most cars made after 1996, this is a straightforward plug-in process that takes just a few minutes.

Older vehicles or those with check engine lights may require a more detailed test. The technician will tell you what type of test your car needs based on its year and condition. You will receive a printed receipt showing whether you passed or failed.

What to do if your car fails the test

A failure means your vehicle's emissions are above the legal limit. Common reasons include a faulty oxygen sensor, a loose gas cap, a catalytic converter problem, or an engine that needs a tune-up. The test results will not tell you exactly what is wrong — only that the emissions are too high.

You have 30 days from the test date to fix the problem and retest. Take your test results to a mechanic, who can diagnose the specific issue. Once repaired, return to any certified testing station (not necessarily the same one) and retest. The retest is free if done within 30 days of the original failure.

Emissions test and vehicle registration renewal

You cannot renew your Chicago vehicle registration without a passing emissions test result. When you renew online or in person at a Secretary of State facility, you will be asked to provide proof of a recent passing test. If you do not have one, the system will not allow you to complete the renewal.

Plan to take your test at least a week before your registration expires, in case you fail and need time to repair and retest. If your registration has already expired, you can still take the emissions test, but you will need to renew your registration when ready after passing.

Special cases and exemptions

Some vehicles are exempt from emissions testing in Chicago. These include vehicles that are less than four model years old (for example, a 2023 car registered in 2024), vehicles with a salvage title, and vehicles registered as non-operational. Diesel vehicles and motorcycles have different testing requirements or may be exempt entirely.

If you believe your vehicle should be exempt, check the Illinois EPA website or ask the testing station technician. They can tell you whether your specific vehicle needs to be tested based on its year, fuel type, and registration status.

Cost and payment

Testing stations charge between $15 and $30 per test. Prices vary by station, so you can call ahead if cost is a concern. Most stations accept cash and cards. If you fail and need to retest within 30 days, the retest is free — you do not pay again.

Some testing stations may charge a small fee if you need to retest after 30 days have passed, so keep your test receipt and plan your repairs accordingly.

Frequently Asked Questions

Can I take the emissions test before my registration expires?

Yes. You can take the test up to 60 days before your registration expires. This gives you time to fix any problems and retest if needed before your renewal important date arrives.

What if I just moved to Chicago — when do I need my first emissions test?

If you registered your vehicle in Chicago for the first time, you will need an emissions test before you can renew that registration. The testing requirement begins with your first renewal cycle in the city.

Do I need an appointment, or can I just walk in?

Most Chicago testing stations accept walk-ins, but some offer appointments. Calling ahead lets you know the wait time and whether that particular station takes appointments. Walk-ins are usually fine, but appointments can be faster during busy periods.

What if my check engine light is on — can I still take the test?

You can take the test with the check engine light on, but you will likely fail. The light usually indicates an emissions-related problem. Get the issue diagnosed and fixed first, then take the test.

How long does a passing test result stay valid?

A passing emissions test is valid for two years from the test date. You must retest before that two-year period ends or your registration will expire and cannot be renewed.