What Air Care Colorado stations do and where to find one
Air Care Colorado is Colorado's vehicle emissions testing program, run by the Colorado Department of Public Health and Environment. When your vehicle is due for emissions testing, you go to an Air Care Colorado station — not a regular mechanic or oil change shop — where technicians plug into your vehicle's computer and measure what comes out of your tailpipe. The test takes about 10 minutes and costs around $20 to $30, depending on the station.
You can find Air Care Colorado stations by visiting the official Air Care Colorado website and using their station locator tool. Enter your zip code and the tool shows you every testing station near you, their hours, and whether they accept walk-ins or require an appointment. Most stations are independent repair shops, not dealerships, and many are open evenings and Saturdays to fit around work schedules.
Not all of Colorado requires emissions testing. The program covers the Denver metro area and a few surrounding counties — roughly the Front Range corridor. If you live outside these areas, you do not need an emissions test. Your vehicle registration paperwork or the Air Care Colorado website will tell you whether your address falls in a testing area.
Key Takeaways
- Air Care Colorado stations test your vehicle's emissions by connecting to your car's computer and measuring tailpipe output, a process that takes about 10 minutes.
- You can locate a nearby station and check its hours using the Air Care Colorado website's station locator tool, which also shows whether appointments are required.
- The test costs between $20 and $30 and must be completed before your vehicle registration expires if you live in a testing area.
- Emissions testing is required only in the Denver metro area and certain surrounding counties; most of Colorado does not require it.
- If your vehicle fails the test, the station provides a report showing which emissions systems need repair before you can retest.
When your vehicle needs an emissions test
Your vehicle needs an emissions test before you can renew your registration if you live in an Air Care Colorado testing area. The important date is your vehicle's registration expiration date — you cannot renew registration without a passing test result. Most people schedule their test a month or two before registration expires to leave time for repairs if needed.
New vehicles registered in Colorado are exempt from testing for their first four model years. After that, every vehicle registered in a testing area must pass an emissions test every two years when registration renews. Vehicles over 25 years old are also exempt, as are electric vehicles and some hybrid models.
When you bring your vehicle in, have your registration paperwork and proof of insurance ready. The technician will verify your vehicle identification number (VIN) matches your registration and then run the test. If your vehicle passes, you receive a passing certificate that you can use to renew your registration online or in person at your county clerk's office.
What happens if your vehicle fails the test
If your vehicle fails an emissions test, the station gives you a detailed report showing which emissions systems are not performing within limits. Common failure reasons include a faulty oxygen sensor, a problem with the catalytic converter, or an issue with the fuel system. The report does not tell you exactly what to fix — that is for a mechanic to diagnose — but it tells you which systems are the problem.
You have until your registration expires to fix the vehicle and retest. You do not have to return to the same station; any Air Care Colorado station can retest your vehicle. Once you pass, you get a new certificate and can renew your registration. If you do not pass before your registration expires, you cannot legally drive the vehicle.
If repairs are expensive and your vehicle is old, some Colorado counties offer programs to help pay for emissions-related repairs or to retire vehicles that cannot pass. Check with your county clerk's office or the Air Care Colorado website to see what programs exist in your area.
How to prepare your vehicle for testing
Before you head to an Air Care Colorado station, make sure your vehicle has been driven recently — at least 20 miles in the last few days. The test measures your vehicle's emissions under normal driving conditions, and a vehicle that has been sitting will not show accurate results. A short drive to the testing station itself is usually enough.
Check that your gas cap is tight and not cracked. A loose or damaged cap can trigger an emissions system warning light and cause a test failure. If your check engine light is on, the vehicle will fail automatically, so have a mechanic scan the code before you test. Many repair shops will scan for free or for a small fee.
You do not need to do an oil change or other maintenance before testing. The emissions test measures only what your vehicle's computer reports and what comes out of the tailpipe — it does not check your brakes, tires, or fluid levels. However, if your vehicle has mechanical problems that are causing emissions issues, those need to be fixed first.
What to bring and what the test costs
Bring your vehicle registration and proof of insurance. Some stations may ask for your driver's license as well. If you are testing a vehicle you recently bought, bring the bill of sale or title transfer paperwork so the technician can verify ownership.
The test itself costs between $20 and $30 at most Air Care Colorado stations. A few stations charge slightly more or less, so call ahead if cost is a concern. If your vehicle fails and you need to retest after repairs, you pay the test fee again. There is no charge if you pass on your first try and then decide not to retest.
Some stations accept cash, credit cards, or both — check the station locator tool or call ahead to confirm payment methods. A few stations may offer discounts for seniors or low-income drivers, though this varies by location. The Air Care Colorado website lists any special programs in your county.
Understanding your test results
A passing result means your vehicle's emissions are within Colorado's limits and you can renew your registration. The certificate is valid for 60 days, so you have time to complete your registration renewal without rushing. You can renew online through the Colorado Department of Revenue website or in person at your county clerk's office.
A failing result shows which emissions systems did not meet standards. The report might say something like "NOx above limit" or "Particulate matter above limit." These terms refer to different pollutants your vehicle is releasing. The report does not diagnose the cause — a mechanic will need to run their own diagnostic to find out whether it is a sensor, a filter, or something else.
If you are unsure what the report means, ask the technician at the station to explain it. They cannot diagnose or repair the problem, but they can tell you what the numbers mean and which systems the test flagged. Write down the specific measurements so you can show them to a mechanic.
What to do if you cannot pass the test
If your vehicle fails and repairs are too expensive, you have a few options. Some Colorado counties run vehicle retirement programs that pay you a small amount to scrap an old vehicle that cannot pass emissions. This is usually available only for vehicles over a certain age and only if you meet income limits. Contact your county clerk's office to ask whether your county has this program.
Other counties offer repair information programs that help pay for emissions-related fixes. These programs typically cover things like catalytic converter replacement or oxygen sensor repair, but not general maintenance. Again, your county clerk's office can tell you what is available in your area.
If you need more time to save for repairs, you can request a registration extension from your county clerk. Extensions are not automatic and are usually granted only if you show proof that you have already started the repair process. Call your county clerk's office to ask about their extension policy.
Frequently Asked Questions
Can I test my vehicle at any Air Care Colorado station, or do I have to go to a specific one?
You can test at any Air Care Colorado station in the state, not just one near your home. If you are traveling or prefer a different location, any station will accept your vehicle. The test result is valid statewide for registration renewal purposes.
What if I just bought a used vehicle and do not know when it was last tested?
Call the Air Care Colorado customer service line or check the website — they can tell you whether your specific vehicle has a recent passing test on file. If it does not, you will need to test before you can register it in Colorado. If you bought it out of state, it will definitely need a test.
Do I have to retest if I fail, or can I just fix the problem and renew my registration?
You must retest and pass before you can renew your registration. A repair receipt alone is not enough — the test must show that your vehicle now meets emissions standards. Retesting costs the same as the initial test.
What if my vehicle passes in one county but I move to another county in Colorado?
Your passing test is valid statewide, so you can renew your registration in your new county without retesting. However, when your registration expires again in two years, you will need to test again in your new location.
Can I test my vehicle before my registration is about to expire?
Yes. You can test up to 60 days before your registration expires. The passing certificate is valid for 60 days, so if you test earlier than that, the certificate will expire before you can use it to renew. Plan to test within two months of your registration expiration date.