Arizona requires emissions testing for most vehicles in the Phoenix and Tucson areas, but not statewide
Arizona does not mandate emissions testing for all vehicles across the state. Instead, the requirement applies only to vehicles registered in Maricopa County (which includes Phoenix) and Pima County (which includes Tucson). These two counties have air quality standards set by the Environmental Protection Agency that require periodic testing. If you register your vehicle outside these counties — in rural Arizona or smaller cities — you do not need to test.
The test itself checks whether your vehicle's emissions fall within state limits for nitrogen oxides, particulate matter, and other pollutants. You must pass before you can renew your vehicle registration. The test costs between $20 and $30 depending on the testing station, and results are valid for two years.
Vehicles model year 1975 and older, electric vehicles, and motorcycles are exempt from testing. Diesel vehicles have separate testing requirements and must be tested at stations equipped to handle them.
Key Takeaways
- Emissions testing is required only in Maricopa County (Phoenix area) and Pima County (Tucson area); most of the rest of Arizona has no testing requirement.
- You must pass the test before you can renew your vehicle registration; the test costs $20 to $30 and is valid for two years.
- You can find testing stations through the Arizona Department of Environmental Quality website or by searching for "emissions testing" in your county.
- If your vehicle fails, you have options: repair it and retest, request a waiver if repairs cost more than a certain amount, or in some cases request an extension to complete repairs.
Where to find an emissions testing station in your county
The Arizona Department of Environmental Quality (ADEQ) maintains a searchable list of authorized testing stations on its website. You can search by county and city to find stations near you. Most stations are independent repair shops, some are chain automotive service centers, and a few are dedicated emissions-testing-only facilities.
When you call or visit a station, confirm they test the type of vehicle you own — some stations test gasoline vehicles only, while others handle diesel or both. You will need your vehicle registration and a valid photo ID. Bring your keys so the technician can start the vehicle and run the test, which typically takes 10 to 15 minutes.
Testing stations report results directly to ADEQ. You do not need to submit anything yourself; the results appear in the system within one business day. You can then renew your registration online, by mail, or in person at your county's motor vehicle division.
What happens if your vehicle fails the test
A failed test does not automatically prevent registration renewal. Arizona offers a repair cost waiver that allows you to register your vehicle even if it fails, provided the cost to repair it exceeds a threshold amount. For the 2024 testing year, that threshold is $366 for most vehicles. If repairs would cost more than that, you can request a waiver and register without passing the test.
If repairs cost less than the threshold, you must complete them and retest. You have until your registration expires to pass. Some testing stations offer repair services on-site, though you are not required to use them — you can take your vehicle to any mechanic.
If you fail and do not may have access to for a waiver, you can request a repair extension in some cases. Contact ADEQ or your county motor vehicle division to ask whether an extension is available in your situation. Extensions are not may provide and depend on the reason for the failure and the time remaining before your registration expires.
Types of vehicles exempt from Arizona emissions testing
Vehicles model year 1975 and older are fully exempt — Arizona considers them historical or classic vehicles. All-electric vehicles are exempt because they produce zero tailpipe emissions. Motorcycles, mopeds, and off-road vehicles are also exempt.
Diesel vehicles are not exempt, but they follow a separate testing protocol. Diesel testing stations use different equipment and procedures than gasoline testing. If you own a diesel vehicle, confirm the station you choose is equipped for diesel before you go.
Vehicles registered outside Maricopa and Pima counties do not need to test at all, regardless of model year or fuel type. If you move your registration to a non-testing county, you no longer need to test. If you move into a testing county, you must test before you can renew.
How to renew your registration after passing the test
Once your vehicle passes the emissions test, the result is automatically recorded in the Arizona Motor Vehicle Division system. You can renew your registration online through the Arizona Department of Transportation (ADOT) website, by mail, or in person at your county's motor vehicle office. You do not need to bring the test result — the system confirms it automatically.
Online renewal is the fastest option and takes a few minutes. You will need your current registration card and a valid payment method. Mail renewal takes one to two weeks. In-person renewal is when ready but requires a trip to the office during business hours.
Your registration renewal notice will arrive in the mail about 45 days before your current registration expires. If you have not passed the emissions test by the time your registration expires, you cannot legally drive the vehicle until you either pass the test or receive a repair cost waiver.
What to do if you move or buy a used vehicle in Arizona
If you move into Maricopa or Pima County from outside Arizona or from a non-testing county within Arizona, you must pass an emissions test before you can register your vehicle in the new county. The test is required as part of the registration process, not before it — you can register with a temporary permit and then test within a set timeframe, usually 30 days.
If you buy a used vehicle in a testing county, the previous owner's test result transfers to you if it is still valid (within two years). You do not need to retest when ready. However, when that test result expires, you will need to test before you can renew your registration.
If you buy a used vehicle from outside a testing county and move it into one, you must test before registration. Some dealerships handle this as part of the sale; others expect you to arrange it yourself. Ask the seller or dealership whether the vehicle has a current passing test result before you complete the purchase.
Frequently Asked Questions
Do I need emissions testing if I just bought a new car?
New vehicles are exempt from testing for the first four model years. After that, they must be tested like any other vehicle in a testing county. Check your registration paperwork or contact ADEQ to confirm your vehicle's exemption status.
What if I fail the test and cannot afford the repairs?
If repairs cost more than $366, you can request a repair cost waiver and register your vehicle without passing. If repairs cost less but you cannot afford them, you cannot legally register the vehicle in a testing county. You may be able to request an extension; contact your county motor vehicle division to ask.
Can I test my vehicle in a different county than where I live?
Yes. You can test at any authorized station in any county. The test result is recorded in the state system and is valid for registration renewal regardless of where you tested. Some people test in whichever county has the shortest wait times.
How often do I need to test after I pass?
A passing test result is valid for two years. You must retest before your registration expires. If you renew your registration before the two-year mark, you do not need to test again until the result expires.
What if the testing station says my vehicle cannot be tested?
Some vehicles have mechanical issues that prevent testing — for example, a check engine light that will not clear, or a fuel cap that does not seal properly. The station will tell you what needs to be fixed before testing can proceed. Once you fix it, you can return to test.