How to find an emissions test location near you

Colorado requires emissions testing in the Denver metro area and several surrounding counties. You can find a testing station by visiting the Colorado Department of Public Health and Environment (CDPHE) website and using their station locator tool, or by calling 303-692-3000 to speak with someone who can direct you to the nearest location.

The locator tool shows you stations by county and city, their hours, phone numbers, and whether they accept walk-ins or require appointments. Most stations are independent repair shops, not dealerships, and many are clustered near major highways and commercial areas where you already drive.

You can also search "emissions testing near me" plus your city name to find stations with current hours and customer reviews. Call ahead before you go—some stations have seasonal closures or limited hours, and a few require you to book a time slot online or by phone.

Key Takeaways

  • The CDPHE station locator is the official source for finding testing locations, hours, and whether each station takes walk-ins.
  • Testing stations are mostly independent repair shops, not dealerships, and are spread across Denver metro and surrounding counties.
  • You need a current vehicle registration and proof of insurance to bring with you when you test.
  • Most tests take 15 to 30 minutes and cost between $25 and $35, though prices vary by station.
  • If your vehicle fails, you have 60 days to repair it and retest at no additional charge at the same station.

What to bring and what to expect during testing

Bring your vehicle registration and proof of insurance. The technician will plug a diagnostic scanner into your vehicle's onboard computer port (located under the steering wheel or dashboard) to read emissions data. The test itself takes 15 to 30 minutes and does not require you to leave the vehicle.

Your vehicle must be in running condition and have a functioning check engine light. If the light is off or broken, the test cannot proceed. The vehicle's engine should be warm but not hot—if you just drove it hard or it has been sitting for hours, wait a few minutes before testing.

The technician will give you a printed result on the spot. A pass means your vehicle meets Colorado standards. A fail means you have 60 days to repair the problem and return to the same station for a free retest. You do not pay again if you fail and come back within that window.

Which Colorado counties require emissions testing

Testing is required in Denver, Adams, Arapahoe, Boulder, Broomfield, Douglas, El Paso, Jefferson, Larimer, and Weld counties. If you live or work in one of these counties and your vehicle is registered there, you must test every two years (or every year if your vehicle is model year 1981 or older).

If you live outside these counties, you do not need to test. If you move into a testing county, you have until your next registration renewal to get your vehicle tested. If you move out of a testing county, you no longer need to test, even if your vehicle previously failed.

What happens if your vehicle fails the emissions test

A failure means your vehicle's emissions are above Colorado limits. The test report will show which pollutants are too high—usually nitrogen oxides, particulate matter, or hydrocarbons. This does not mean your vehicle is unsafe to drive, but it does mean you cannot renew your registration until you repair it and pass a retest.

Take the failure report to a repair shop. Many shops can diagnose the problem from the report alone. Common fixes include replacing a faulty oxygen sensor, fixing a vacuum leak, or replacing a clogged air filter. Costs vary widely depending on the problem—$50 to $500 is typical, though some repairs cost more.

Once you repair the vehicle, return to the same testing station within 60 days for a free retest. If you pass the second time, you can renew your registration. If you fail again, you have another 60 days to repair and retest. After two failed retests, you may be required to visit a CDPHE repair facility for a third opinion before you can register the vehicle.

Testing costs and payment methods

Emissions tests cost between $25 and $35 depending on the station. Most stations accept cash, debit, and credit cards. A few accept only cash, so call ahead if you want to confirm payment options.

If you fail and need a retest, the retest is free at the same station within 60 days. You do not pay twice. If you go to a different station for a retest, you will pay the full test fee again.

Online appointment booking and walk-in options

Some Colorado testing stations accept walk-ins during posted hours. Others require you to book an appointment online or by phone. The CDPHE locator tool shows which stations in your area take walk-ins and which require scheduling.

If a station requires appointments and you cannot find an open slot, call the station directly—cancellations happen frequently, and staff can sometimes fit you in the same day. During peak testing months (August through October), wait times are longer, so testing earlier in the year can save you time.

Frequently Asked Questions

Can I test my vehicle in a different county than where it is registered?

Yes. You can test at any station in any testing county. The results are valid for registration renewal in your home county. This is useful if you work in a different county or find a station with shorter wait times nearby.

What if my check engine light is on?

Your vehicle will fail the emissions test if the check engine light is illuminated. Have the vehicle scanned at a repair shop to find out why the light is on, fix the problem, and clear the light before you test. Testing stations cannot clear the light for you.

Do I need to test if I just bought a used vehicle in Colorado?

If you register the vehicle in a testing county, you must test it before or at the time of registration. Bring the test results to the DMV when you register. If you buy the vehicle from a dealer, ask whether they have already tested it—some dealers test before sale to speed up the process.

What if I cannot afford the repair after a failed test?

Colorado does not have a waiver program for failed emissions tests. You must repair the vehicle and pass a retest to renew registration. If the repair is expensive, get quotes from multiple shops—prices vary significantly. Some nonprofits and community colleges offer low-cost repair services; call 211 Colorado to ask about programs in your area.

How long does a retest take if I fail?

A retest takes the same 15 to 30 minutes as the original test. You have 60 days from the failure date to return to the same station. If you miss the 60-day window, you must pay for a new full test and start the process over.