Emissions Testing in Arizona

Testing Requirements

Current Testing Requirements in Arizona

Arizona operates a mandatory emissions testing program in the Phoenix and Tucson metro areas. The program is run by ADEQ under Arizona Revised Statutes Title 49, Chapter 3, Article 5. Area A covers portions of Maricopa County and parts of Pinal and Yavapai counties surrounding metro Phoenix. Area B covers the Tucson metro area within Pima County. The test type depends on the vehicle's model year, weight, fuel type, and registration area. Vehicles from 1996 and newer under 8,500 pounds receive an OBD-II diagnostic test. Older gasoline vehicles undergo a dynamometer-based IM 147 test or a steady-state idle test. Diesel vehicles receive tailpipe opacity testing or OBD-II testing depending on model year and weight.

Who Needs an Emissions Test or Smog Check

Most gasoline vehicles from model year 1967 and newer registered in Area A or Area B must pass an emissions test. This includes cars, trucks, SUVs, RVs, and motorhomes. Diesel vehicles model year 1997 and newer in the Phoenix area and all diesel vehicles in the Tucson area also require testing. Vehicles used to commute into a testing area for work or school must be tested even if the owner lives outside the boundary. New vehicles are exempt for their first five model years from the date of initial registration. Motorcycles, electric vehicles, collectible vehicles with collectible-car insurance, and vehicles manufactured before 1967 are exempt. Hybrid and flexible fuel vehicles are not exempt and must test on the same schedule as gasoline vehicles.

How Often Tests Are Required

Testing frequency depends on the vehicle type, model year, weight, and registration area. In the Phoenix area, gasoline vehicles from model year 1981 and newer weighing under 8,500 pounds test every two years. Gasoline vehicles from 1967 to 1980, vehicles over 8,500 pounds, and all diesel vehicles test annually. In the Tucson area, gasoline vehicles from model year 1996 and newer weighing under 8,500 pounds test every two years. Gasoline vehicles from 1967 to 1995, vehicles over 8,500 pounds, and diesel vehicles test annually. Testing must be completed no more than 90 days before registration expiration. The registration renewal notice from ADOT will indicate whether a test is required.

Where Emissions Testing Is Required

Emissions testing is required in two designated areas. Area A covers the greater Phoenix metropolitan region, including most of Maricopa County and parts of Pinal County and Yavapai County. Area B covers the Tucson metropolitan area within Pima County. The exact boundaries are defined by township and range, not by county lines. Some zip codes along the boundary are partially inside and partially outside the testing area. Drivers can check their specific address using the ADEQ online address locator at myAZcar.com. Vehicles registered outside both areas are exempt unless the owner commutes into an area for work or school.

What Happens During the Test

The test procedure depends on the vehicle. For 1996 and newer gasoline vehicles under 8,500 pounds, a technician connects an OBD-II scanner to the vehicle's diagnostic port and checks for trouble codes, readiness monitor status, and the malfunction indicator lamp. For 1981 to 1995 gasoline vehicles under 8,500 pounds in the Phoenix area, the vehicle is driven on a dynamometer during an IM 147 test that measures hydrocarbons, carbon monoxide, and nitrogen oxides. Older vehicles and heavier vehicles receive a steady-state idle or loaded idle test. Diesel vehicles receive either an OBD-II test or an opacity test depending on model year and weight. A lit check engine light is an automatic failure. Vehicles should have at least half a tank of fuel before testing. The test typically takes 10 to 20 minutes.

Areas in Arizona That Require Emissions Testing

Arizona requires emissions testing only in the Phoenix and Tucson metro areas. Within the Phoenix testing boundary (Area A), cities include Phoenix, Scottsdale, Mesa, Tempe, Chandler, Gilbert, Glendale, Peoria, Surprise, Goodyear, Avondale, Buckeye, Fountain Hills, Cave Creek, and parts of Apache Junction and Queen Creek. Within the Tucson testing boundary (Area B), the area includes Tucson, Oro Valley, Marana, and South Tucson. Cities and towns outside these boundaries have no testing requirements. Flagstaff, Yuma, Prescott, Lake Havasu City, Sierra Vista, Kingman, Bullhead City, and Sedona do not require emissions testing. Rural areas throughout the state are exempt. ADEQ operates multiple testing stations across both metro areas, and real-time wait times are available on the myAZcar.com website.

How the Emissions Test Works in Arizona

Drivers take their vehicle to any ADEQ-operated emissions testing station in the Phoenix or Tucson area. No appointment is needed. Stations are open Monday through Friday from 8 a.m. to 5 p.m. and Saturdays with reduced hours. Bring your vehicle registration and payment. The fee is $17 for gasoline vehicles in the Phoenix area and $12.25 in the Tucson area. Heavy-duty diesel vehicles pay $25 in Phoenix. The technician performs the appropriate test based on the vehicle's model year, fuel type, and weight. Results are transmitted electronically to ADOT. If the vehicle passes, no paperwork is needed at the MVD office and registration can be renewed online. If the vehicle fails, the owner receives a vehicle inspection report with the failure codes. A free retest is available within 60 days of the initial failure. Owners who cannot afford repairs may qualify for the Voluntary Vehicle Repair Program (VVRP), which pays up to $900 toward emissions-related repairs at an approved facility. The owner pays a $100 copay plus any costs above the program cap. The vehicle must be registered in Maricopa or Pima County to qualify. If the vehicle fails twice in the same test cycle and exceeds the repair cost limit, the owner may apply for a waiver at a state waiver facility. Waivers cannot be issued for vehicles with removed or tampered emissions equipment or vehicles emitting more than twice the applicable standard.