What Air Care Colorado Does

Air Care Colorado is Colorado's vehicle emissions testing program, run by the Colorado Department of Public Health and Environment. It tests whether your vehicle's exhaust meets state air quality standards. If you live in one of Colorado's eight designated air quality areas — which include Denver, Boulder, Fort Collins, and Colorado Springs — you must pass an Air Care test before you can register your vehicle each year.

The program exists because these regions don't meet federal air quality standards on their own. Vehicle emissions are a measurable source of that pollution, so the state requires testing to identify and remove the worst polluters from the road. If your vehicle fails, you get a chance to repair it and retest at no additional fee.

Air Care is separate from your regular vehicle inspection. You need both: the safety inspection checks your brakes and lights; Air Care checks your emissions. Some testing stations do both, but they are different tests with different requirements.

Key Takeaways

  • Air Care Colorado is required in eight air quality areas across the state, and you must pass before you can register your vehicle.
  • The test measures your vehicle's exhaust emissions; most vehicles pass on the first try if they are in reasonable working condition.
  • If you fail, you can repair your vehicle and retest for free at the same station.
  • You can find testing stations and check your vehicle's history through the Air Care Colorado website or by calling their customer service line.
  • Vehicles older than model year 1982, diesel vehicles, and some hybrids are exempt from testing.

Which Colorado Counties and Cities Require Air Care Testing

Air Care testing is required in eight air quality areas. The largest is the Denver metropolitan area, which includes Denver, Aurora, Littleton, Boulder, Broomfield, and surrounding parts of Adams, Arapahoe, Boulder, Broomfield, Douglas, Jefferson, and Weld counties. Fort Collins and Loveland in Larimer County also require testing, as do Colorado Springs and El Paso County, Greeley and Weld County, and Pueblo County.

If you live outside these areas, you do not need an Air Care test. You still need a safety inspection to register your vehicle, but emissions testing is not required. If you are unsure whether your address falls within an Air Care area, the Air Care Colorado website has a zip code lookup tool, or you can call their customer service line to confirm.

How the Air Care Test Works

The test itself takes about 10 minutes. You drive to a testing station, where a technician plugs a probe into your vehicle's diagnostic port — usually located under the steering wheel or dashboard. The probe reads your vehicle's onboard computer and measures tailpipe emissions. For most vehicles, the test is non-intrusive and requires no physical work on your part.

Your vehicle passes if its emissions fall below the state limits for your vehicle's model year and engine type. The limits are stricter for newer vehicles and less strict for older ones, because newer engines are designed to produce fewer emissions. A vehicle that runs well and has no check-engine light usually passes without trouble.

If you fail, the testing station gives you a failure notice that explains what failed — usually one of three things: hydrocarbons (unburned fuel), nitrogen oxides (a byproduct of combustion), or carbon monoxide (incomplete combustion). You then have 60 days to repair your vehicle and retest at no charge. The retest must happen at the same station where you failed.

Which Vehicles Are Exempt From Air Care Testing

Not all vehicles need to be tested. Vehicles manufactured before model year 1982 are exempt, as are all diesel vehicles. Some hybrid vehicles are also exempt depending on their model year and configuration. Motorcycles and mopeds do not require Air Care testing either.

If your vehicle is exempt, you still need to register it in Colorado, but you do not need an Air Care test. When you register, you will not be asked for an Air Care certificate. If you are unsure whether your vehicle is exempt, the Air Care website lists exemptions by vehicle type, or you can ask a testing station when you call to schedule.

How to Find a Testing Station and Schedule

The Air Care Colorado website has a station locator tool where you can search by zip code or city. It shows you the address, phone number, hours, and whether each station accepts walk-ins or requires an appointment. Some stations are dedicated Air Care facilities; others are repair shops or tire shops that also do Air Care testing.

Call ahead before you go. Many stations accept walk-ins, but some require appointments, especially during peak times like the end of the month. When you call, have your vehicle's license plate number ready. The station may ask for it to look up your vehicle's history and confirm that you have not already been tested this registration year.

Bring your vehicle registration or proof of ownership. You do not need to bring anything else. The test takes about 10 minutes, and you get your results on the spot. If you pass, the station sends your results to the Colorado Department of Revenue, and you can register your vehicle when ready.

What Happens If You Fail and Need to Repair

A failure notice tells you which emission standard your vehicle did not meet. Common reasons for failure are a faulty oxygen sensor, a clogged fuel injector, a bad catalytic converter, or an engine that is running too rich (burning too much fuel). A mechanic can diagnose the specific problem by reading your vehicle's diagnostic codes.

You have 60 days from the date of your failed test to repair your vehicle and retest. The retest must happen at the same station. When you return, bring your failure notice and your vehicle. The retest is free, and if you pass, your results are sent to the state when ready.

If you fail a second time, you can continue to retest for free within the 60-day window. Some vehicles need multiple repairs before they pass. If you cannot get your vehicle to pass within 60 days, you can request a waiver from the Air Care program. A waiver allows you to register your vehicle even though it failed, but you must show that you made a good-faith repair attempt and spent at least a certain amount of money (the threshold varies by year and vehicle type). Contact Air Care customer service to request a waiver process.

Registration and Your Air Care Results

Once you pass an Air Care test, the testing station sends your results electronically to the Colorado Department of Revenue. You do not need to print anything or bring a certificate to the DMV. When you register your vehicle online, by mail, or in person, the state automatically checks whether you have a passing Air Care result on file.

If you have a passing result, your registration will process normally. If you do not have a passing result and you live in an Air Care area, your registration will be denied until you pass the test. You can register your vehicle as soon as your passing result appears in the state system, which usually happens within one business day of your test.

Your Air Care result is good for one registration year. When your registration expires and you renew it, you will need a new Air Care test. The program does not carry results over from year to year.

Frequently Asked Questions

Can I register my vehicle if I have not passed Air Care yet?

No. If you live in an Air Care area, the state will not issue or renew your registration without a passing Air Care result on file. You must pass the test before you can legally register your vehicle. If your registration has already expired, you cannot legally drive the vehicle until you register it.

What if I just bought a used car and it fails Air Care?

You have 60 days from the test date to repair and retest for free. If the vehicle is still under a dealer's warranty, contact the dealer — they may cover emissions-related repairs. If not, you will need to pay for repairs yourself. Keep your repair receipts in case you need to request a waiver later.

Do I need Air Care if I am registering a vehicle for the first time in Colorado?

Yes, if you live in an Air Care area. Even new vehicle registrations require a passing Air Care result before the state will issue plates. The only exception is if your vehicle is exempt (pre-1982, diesel, or certain hybrids).

What if I move out of an Air Care area?

You no longer need Air Care testing once you move outside the eight designated areas. When you register your vehicle in your new county, you will not be asked for an Air Care result. If you move back into an Air Care area later, you will need to pass Air Care again before you can register.

How much does Air Care testing cost?

Testing fees vary by station, typically ranging from $10 to $25 per test. Retests after a failure are free. Call your local testing station for their exact fee, or check the Air Care website station locator, which lists prices for many stations.