What Aurora requires and when you need to test

Aurora is part of the Denver metro area, which sits in the North Front Range Air Quality Control Region. That region requires emissions testing for most vehicles registered there. If you register a car, truck, or motorcycle in Aurora, you will need to pass an emissions test before you can renew your registration — with a few exceptions for very new vehicles and electric cars.

The Colorado Department of Transportation (CDOT) and the Colorado Department of Public Health and Environment (CDPHE) jointly oversee the program. Aurora itself does not run the testing stations; instead, the state contracts with private testing facilities across the city. You choose which station to visit.

Testing is required every two years for most vehicles. If your vehicle was first registered in Colorado less than four model years ago, you may be exempt from testing in your first year of registration. Electric vehicles and plug-in hybrids are exempt entirely. Vehicles model year 1981 and older are also exempt, though you will still need to register them.

Key Takeaways

  • Aurora requires emissions testing every two years as part of vehicle registration renewal, and you must pass before the state will issue your registration sticker.
  • Testing costs between $20 and $30 per vehicle at state-contracted private facilities scattered throughout Aurora; the state sets the maximum price, but individual stations may charge less.
  • You can find testing stations and schedule appointments through the Colorado Department of Transportation website or by calling the CDPHE air quality hotline.
  • If your vehicle fails, you have 60 days to repair it and retest at no additional charge at the same station, or you can take it elsewhere and pay again.
  • Vehicles model year 1981 and older, electric vehicles, plug-in hybrids, and new vehicles in their first registration year are exempt from testing.

Finding a testing station in Aurora and what to bring

The Colorado Department of Transportation maintains a searchable list of all contracted testing stations on its website. You can filter by city and see the station name, address, phone number, and hours. Most Aurora stations are open during standard business hours, though some offer evening or Saturday appointments. Call ahead to confirm hours before you drive over, as individual stations set their own schedules within state guidelines.

Bring your vehicle registration, proof of insurance, and a valid photo ID. The technician will run your vehicle's identification number (VIN) through the state system to pull up your registration record. If you are renewing registration for the first time at that station, bring your current registration document. If you have had repairs done since your last test, bring the repair receipts — they are not required to pass, but they can help if your vehicle is borderline on emissions levels.

The test itself takes 10 to 15 minutes. The technician will connect a probe to your vehicle's tailpipe and measure emissions of nitrogen oxides, carbon monoxide, and particulate matter. For 1996 and newer vehicles, the technician will also read your onboard diagnostic system (OBD) to check for engine trouble codes. The vehicle must be warmed up but not overheated; if you have just driven it hard, let it cool for a few minutes before the test begins.

Cost and what happens if you fail

Testing costs between $20 and $30 per vehicle. The state sets the maximum price, but individual stations may charge less. Some stations accept cash, credit, or debit; a few accept only one or two methods, so call ahead if you have a payment preference. The fee is separate from your registration renewal fee, which you pay to the Colorado Division of Motor Vehicles.

If your vehicle passes, the station will issue a certificate of compliance. You will need this certificate or the station's confirmation number when you renew your registration online, by mail, or in person at a DMV office. If your vehicle fails, you have 60 days to repair it and return to the same station for a retest at no additional charge. If you choose to test at a different station after repairs, you will pay the full testing fee again.

Common reasons for failure include a faulty oxygen sensor, a loose or missing gas cap, a malfunctioning catalytic converter, or an engine trouble code triggered by a worn spark plug or air filter. Many of these repairs cost between $100 and $500. If repair costs are high, you can research whether your vehicle qualifies for the Colorado Vehicle Emissions Repair information Program, which may help cover costs for low-income vehicle owners.

Scheduling and timing around registration renewal

Your registration renewal notice will arrive 60 days before your registration expires. The notice will state your testing important date, which is typically 60 days before expiration. You do not have to wait until the last minute; you can test as soon as you receive the notice. Testing early gives you time to repair and retest if needed.

You can schedule an appointment at most Aurora stations through the Colorado Department of Transportation website or by calling the station directly. Walk-ins are usually accepted, but wait times vary. During peak months (August through October, when many people renew before winter), stations can have waits of 30 minutes to an hour. Scheduling an appointment typically guarantees you a slot within a few days.

If you test and pass, you can renew your registration when ready online at the Colorado Division of Motor Vehicles website, by mail, or at a local DMV office. Online renewal is fastest and requires only your certificate number or the station's confirmation. Registration renewal itself costs between $100 and $200 depending on your vehicle type and whether you add optional services like a personalized plate.

What to do if your vehicle fails and repair options

If your vehicle fails, the test report will list which emissions standards it did not meet and which systems may be responsible. The report is not a diagnosis; it tells you what failed, not always why. A mechanic will need to run a full diagnostic to pinpoint the cause. Many independent mechanics and dealerships in Aurora offer pre-test diagnostics for $50 to $150, which can save you money by identifying the problem before you start repairs.

You have 60 days from the test date to repair and retest. If you repair at the same station where you failed, the retest is free. If you repair elsewhere and want to retest at a different station, you will pay the full testing fee again. Some people choose to shop around for repair quotes before deciding where to test the second time.

If repair costs are high and your household income is at or below 200 percent of the federal poverty line, you may be able to get help through the Colorado Vehicle Emissions Repair information Program. This program can cover up to $500 in repair costs. You will need to contact the program directly through the Colorado Department of Public Health and Environment to learn about current funding and how the process works.

Exemptions and special cases in Aurora

Vehicles model year 1981 and older do not require emissions testing, even in the Denver metro area. Electric vehicles, plug-in hybrids, and hydrogen fuel cell vehicles are exempt. Vehicles first registered in Colorado within the current model year and the three previous model years may be exempt in their first registration year; check your renewal notice to see whether your vehicle qualifies.

Vehicles registered as antiques or classics (usually 25 years or older and driven fewer than 5,000 miles per year) are also exempt. If your vehicle is registered as an antique, your registration document will say so. Motorcycles and mopeds registered in Aurora are subject to testing, though some older motorcycles may be exempt depending on model year.

If you believe your vehicle should be exempt but your renewal notice says you need to test, contact the Colorado Division of Motor Vehicles or the CDPHE air quality section. Bring your registration document and any proof of the vehicle's age or classification. Disputes over exemptions are usually resolved within a few business days.

Frequently Asked Questions

Can I renew my registration without an emissions test?

No, not if your vehicle is subject to testing. The Colorado Division of Motor Vehicles will not issue a registration renewal sticker without a passing emissions certificate or proof of exemption. If you try to renew online without the certificate, the system will reject your request and ask you to test first.

What if I move out of Aurora but still have a Colorado registration?

If you move to a county outside the North Front Range Air Quality Control Region, you will no longer need emissions testing. When you renew your registration at your new address, the DMV will update your testing requirement. If you move to another area within the region (like Boulder or Fort Collins), you will still need testing.

How long does it take to get results after I test?

You receive your results when ready at the testing station. If you pass, the technician will give you a certificate or confirmation number on the spot. If you fail, you will get a detailed report showing which standards you did not meet. You can then renew your registration right away if you passed, or schedule repairs if you failed.

What if I cannot afford the repair costs?

The Colorado Vehicle Emissions Repair information Program may help if your household income is at or below 200 percent of the federal poverty line. The program can cover up to $500 in repair costs. Contact the Colorado Department of Public Health and Environment to learn whether funding is currently available and how to request help.

Do I need to test if I just bought a used car in Aurora?

Only if the registration is in your name and the renewal date has arrived. If you buy a car and transfer the title to yourself, you will inherit the previous owner's registration expiration date. When that date approaches, you will receive a renewal notice that will tell you whether testing is required based on the vehicle's model year and exemption status.