What Longmont requires for emissions testing

Longmont requires emissions testing for most vehicles registered in the city, with some exceptions based on model year and vehicle type. The test measures tailpipe emissions to may support your vehicle meets Colorado air quality standards. You must pass an emissions test before you can renew your vehicle registration with the Colorado Department of Revenue.

Vehicles typically need testing every two years, though some newer vehicles may may have access to for longer intervals depending on their age and emissions history. Diesel vehicles, motorcycles, and vehicles registered outside Colorado have different requirements. Your registration renewal notice will indicate whether your vehicle needs testing in that cycle.

The test itself takes about 10 to 15 minutes and costs between $20 and $30, depending on the testing facility. You'll need your vehicle's VIN, current registration, and proof of insurance to complete the test.

Key Takeaways

  • Longmont emissions testing is required every two years for most vehicles before you can renew your registration.
  • The test measures tailpipe emissions and costs $20 to $30 at any Colorado-certified testing facility.
  • Your registration renewal notice will tell you whether your vehicle needs testing that year.
  • You must bring your VIN, current registration, and proof of insurance to the testing facility.
  • Vehicles that fail emissions can often be retested at no additional cost after repairs are made.

Where to get tested in Longmont

Longmont has several Colorado-certified emissions testing stations. You can find a complete list of approved facilities through the Colorado Department of Revenue's website or by calling the Longmont Air Quality Division. Testing stations are typically located at service stations, tire shops, and dedicated emissions testing centers throughout the city.

You do not have to test at a facility in Longmont itself — you can use any Colorado-certified station anywhere in the state. However, testing locally is usually more convenient. Call ahead to confirm hours and whether the facility has availability, as some stations get busy during peak renewal periods (typically late in the month or late in the year).

What happens if your vehicle fails the test

A failed emissions test does not prevent you from driving your vehicle when ready, but you cannot renew your registration until you pass. You have 60 days from the test date to retest at no charge if you make repairs. Keep your failed test report — you'll need it to show the testing facility that you're retesting after repairs.

Common reasons for failure include a faulty oxygen sensor, a loose gas cap, or a malfunctioning catalytic converter. A mechanic can diagnose the specific problem using your test results. Some repairs are inexpensive (a gas cap costs $10 to $20), while others like catalytic converter replacement can run several hundred dollars.

If repairs are too costly, Colorado offers a Repair information Program for vehicles that fail emissions testing. The program provides up to $500 toward repairs for low-income vehicle owners. You can learn more through the Colorado Department of Public Health and Environment.

Emissions testing for older and specialty vehicles

Vehicles older than 1975 are exempt from emissions testing in Colorado. Vehicles from 1975 to 1981 may also be exempt depending on their registration status. Diesel vehicles registered before 2000 have different testing requirements than gasoline vehicles.

Motorcycles, mopeds, and off-road vehicles are not subject to emissions testing. If you own a vehicle that you believe should be exempt, check your registration renewal notice or contact the Longmont Air Quality Division to confirm your vehicle's testing status before you pay for a test you don't need.

Renewing your registration after passing the test

Once you pass the emissions test, the testing facility sends the results electronically to the Colorado Department of Revenue. You can then renew your registration online through the DMV website, by mail, or in person at a county clerk's office. You do not need to bring the test certificate — the state receives it automatically.

Registration renewal can be completed up to 90 days before your registration expires. If you wait until after expiration, you may face late fees. The renewal fee varies by vehicle type and county, but typically ranges from $100 to $200 for a standard passenger vehicle.

Understanding Longmont's air quality standards

Longmont is part of the Denver-Boulder-Greeley air quality region, which has stricter emissions standards than some other parts of Colorado. The city sits in a valley where air can stagnate, making local emissions control important for meeting federal air quality standards. Vehicles that pass Longmont's test will pass anywhere in Colorado.

The emissions test measures nitrogen oxides (NOx) and particulate matter, which contribute to smog and respiratory problems. By maintaining your vehicle and keeping it in good repair, you reduce emissions and help the region meet air quality goals.

Frequently Asked Questions

Can I renew my registration without getting an emissions test?

No, if your vehicle is required to test, you cannot complete registration renewal without a passing test result. The Colorado Department of Revenue will not process your renewal until the test is submitted. Check your renewal notice to see if your vehicle is exempt.

What if I just moved to Longmont and my vehicle was registered elsewhere?

You must re-register your vehicle in Colorado within 90 days of establishing residency. At that time, you'll need an emissions test if your vehicle is subject to testing. You can use any Colorado-certified facility, not just one in Longmont.

How long does the emissions test take?

The actual test takes 10 to 15 minutes. However, you may wait 30 minutes to an hour depending on how busy the facility is. Arriving early in the day or on weekdays typically means shorter waits than late afternoon or weekends.

Do I need to make an appointment for emissions testing?

Most Longmont testing facilities accept walk-ins, but some accept appointments. Call ahead to ask whether the station you plan to visit requires an appointment or operates on a first-come, first-served basis.

What if my vehicle has a check engine light on?

A check engine light usually means your vehicle will fail the emissions test. Have the problem diagnosed by a mechanic before testing. Once the issue is repaired and the light is off, you can retest at no charge within 60 days of your original test.