Westminster's emissions testing location and hours
Westminster operates an emissions testing station at 10500 Melody Drive, Westminster, Colorado 80021. This is the primary location where residents can bring vehicles for state-required emissions tests. The station is open Monday through Friday, 8 a.m. to 5 p.m., and Saturday from 9 a.m. to 1 p.m. It is closed on Sundays and state holidays.
The station does not accept walk-ins without an appointment. You must schedule a test time in advance through the Colorado Department of Revenue's online system or by calling the station directly. Appointment slots typically fill up several weeks ahead during peak testing seasons (spring and fall), so plan accordingly if your registration renewal is approaching.
The facility is located in the northwest part of Westminster, near the intersection of 104th Avenue and Melody Drive. Parking is available on-site. If you are unsure whether you need an emissions test, check your vehicle registration notice — it will state whether your vehicle is subject to testing in your county.
Key Takeaways
- Westminster's emissions station is at 10500 Melody Drive and requires an appointment booked in advance through the Colorado Department of Revenue system.
- The station operates weekdays 8 a.m. to 5 p.m. and Saturdays 9 a.m. to 1 p.m., with peak wait times in spring and fall when registration renewals cluster.
- Bring your vehicle registration, proof of insurance, and a valid ID; the test itself takes 10 to 15 minutes once you are called in.
- If your vehicle fails, you have 60 days to repair it and return for a retest at no additional fee, or you can visit a different testing station.
- The test costs a flat fee set by the state; Westminster station does not set its own pricing and accepts cash, card, and check.
What documents and information to bring
Bring your current vehicle registration and a valid photo ID. The registration shows your vehicle identification number (VIN), which the technician will verify matches the vehicle you are testing. You will also need proof of current insurance, though the station does not verify coverage — it is a legal requirement to have it while driving.
Have your odometer reading available or visible on your dashboard. The technician will record the mileage as part of the test record. If you have had recent repairs or maintenance done, bring receipts showing work on the emissions system, fuel system, or engine — these can be helpful if your vehicle fails and you need to dispute the result or show a mechanic what has already been checked.
If you are testing a vehicle registered to someone else, bring a signed letter from the registered owner authorizing you to test it on their behalf. The station will not test a vehicle if the person present cannot prove they have permission to do so.
How the emissions test works and what happens during it
The test measures your vehicle's exhaust emissions and checks the onboard diagnostic system. For most vehicles, the technician will connect a probe to your vehicle's tailpipe and run the engine at idle and at a higher RPM to measure carbon monoxide, nitrogen oxides, and particulate matter. The entire process takes 10 to 15 minutes once you are called from the waiting area.
Your vehicle must be warmed up before testing. If you arrive with a cold engine, the technician may ask you to wait a few minutes or drive around the parking lot to bring the engine to operating temperature. The test cannot proceed accurately on a cold engine, and a failed cold-engine test does not count against you.
During the test, you will remain in the waiting area. The technician handles all equipment and does not require your input. Once the test is complete, you will receive a printed result when ready — either a pass or a fail. A pass means your vehicle meets Colorado's emissions standards for your vehicle model year and type. A fail means you must have repairs made before the vehicle can be registered.
What to do if your vehicle fails the test
If your vehicle fails, you have 60 days from the test date to have repairs made and return for a retest. The retest is free — you pay only once, at the initial test. You do not need to book a new appointment for the retest; you can walk in during regular hours, though calling ahead is still recommended to avoid a long wait.
Take the fail notice to a repair shop or mechanic. The notice will list which emissions systems did not meet standards. A mechanic can use this information to diagnose what needs repair. Common failures involve the catalytic converter, oxygen sensors, fuel injectors, or the check engine light being on. Repairs can range from $50 to several hundred dollars depending on what is wrong.
If you believe the test result is incorrect, you can request a retest at a different Colorado emissions testing station. Each station uses calibrated equipment, and a second test can confirm whether the failure was accurate. Some stations are located in nearby areas like Broomfield, Thornton, and Boulder if you want a second opinion before spending money on repairs.
Fees and payment methods accepted
Colorado sets a statewide emissions testing fee. The exact amount varies slightly by station but is typically in the range of $25 to $30 for a standard test. Westminster station charges the state-set rate and does not add local surcharges. The fee covers one test; a retest after a failure is included at no additional cost.
The Westminster station accepts cash, debit card, and credit card. It also accepts personal checks if you prefer to pay that way. Ask for a receipt — you will need it if you dispute a result or if your registration paperwork requires proof of testing.
Some Colorado counties offer fee waivers or reduced-cost testing for low-income vehicle owners. Check with the Westminster station or the Colorado Department of Revenue to see whether Adams County (where Westminster is located) has such a program. If you may have access to, bring documentation of your income when you arrive for your test.
Peak testing times and how to avoid long waits
The busiest times at Westminster station are March through May and August through October, when vehicle registrations renew in clusters. If your registration renewal notice gives you a window of several months, schedule your test in January, February, June, July, November, or December to encounter shorter lines and faster appointment availability.
Saturday morning appointments, while limited, often have shorter waits than weekday afternoons. If you can take a morning slot on Saturday, you may spend less time waiting overall. Arriving early in the day on a weekday also tends to be faster than late afternoon, when people often test vehicles after work.
If the Westminster station is fully booked, you can test at any other Colorado emissions station and the result will be valid for your registration renewal. Nearby alternatives include stations in Broomfield, Thornton, and Boulder. Your registration does not require testing at a specific location — any state-certified station will do.
What happens after you pass the test
Once you pass, the test result is transmitted electronically to the Colorado Department of Revenue. You will receive a printed pass notice on the spot. Keep this notice with your vehicle registration documents until your registration is renewed, though you do not need to submit it separately — the state's system already has the record.
Your registration can now be renewed. You can renew online through the Colorado Department of Revenue website, by mail, or in person at your county clerk's office. The emissions test result is valid for two years from the test date, so if your registration renewal is delayed, you do not need to test again as long as you renew within that window.
If you sell the vehicle before the registration expires, the new owner will need a current emissions test if the vehicle is subject to testing in their county. The test does not transfer with the vehicle — each owner must test when their registration comes due.
Frequently Asked Questions
Can I test my vehicle if the check engine light is on?
No. The check engine light indicates a fault in the emissions system, and the technician will not proceed with the test until it is resolved. You must have the vehicle scanned by a mechanic to identify the fault, have it repaired, and confirm the light is off before returning to test. This is a safety requirement, not a choice.
What if I move out of Westminster or Adams County after I test?
Your emissions test result is valid statewide for two years. If you move to a different Colorado county, you can use the same test result for your registration renewal there, as long as the test is still within the two-year window. You do not need to retest when you move.
Do I need an appointment if I am retesting after a failure?
Retests are free and do not require an appointment, though calling ahead to check wait times is still a good idea. You can walk in during regular hours with your original fail notice. If the station is very busy, you may wait longer than at your first test, so arriving early in the day is recommended.
What if my vehicle is too old or too new to test?
Vehicles older than a certain model year (typically 1975 and earlier) are exempt from testing. Very new vehicles (usually the current model year) may also be exempt. Your registration notice will state whether your vehicle is subject to testing. If you are unsure, call the Westminster station or check the Colorado Department of Revenue website with your VIN.
Can I test a vehicle that is not registered in Colorado?
No. The emissions test is tied to Colorado vehicle registration. If your vehicle is registered in another state, you cannot test it at Westminster. If you are moving to Colorado and registering a vehicle here, you will need to test it as part of the registration process, but only after you have established Colorado residency and begun the registration process.