Frequently Ask Questions

An Emissions test determines the level of air pollutants emitted from your vehicle's exhaust. The first emissions testing was done in California in 1966. Since 1966, many states, including California, began requiring testing for all registered vehicles. If your vehicle fails, repairs are required.

California uses the following criteria to determine if your vehicle is STAR station designated: 1 Your vehicle was determined to be a gross polluter in previous years 2 The vehicle's make and model is determined to fit the High Emitter Profile 3 Determined randomly from a list of all driven vehicles

The Smog Check Program, established in 1984, aims to enhance air quality by inspecting and maintaining vehicles. It detects those with excessive emissions and ensures they are either fixed or removed from the road. As a result, the program has significantly lowered the amount of pollution caused by vehicles in California.

The Smog Check program is administered by the Bureau of Automotive Repair (BAR) and independently-owned Smog Check stations are licensed by them throughout California.

As part of the vehicle registration process, a Smog Check is mandatory every two years. The Department of Motor Vehicles (DMV) registration renewal notice will specify if a Smog Check is necessary. Additionally, a Smog Check is mandatory when a vehicle is being transferred or registered for the first time in California.

Gasoline-powered, hybrid, and alternative-fuel vehicles that are model-year 1976 or newer require a Smog Check, except for the following:

• Vehicles that are 8 model years or newer are exempt from biennial Smog Check.

• Vehicles that are 4 model years or newer are exempt from change-of-ownership Smog Check.

To determine the first year a vehicle requires a biennial or change-of-ownership Smog Check, add 8 or 4 to the model year of the vehicle respectively.

For instance, a 2020 model-year vehicle will first be subject to a biennial Smog Check-in 2028 (2020 + 8 = 2028) and will require a change-of-ownership Smog Check if sold in or after 2024 (2020 + 4 = 2024).

• As for diesel-powered vehicles, those that are model-year 1998 or newer with a gross vehicle weight rating of 14,000 pounds or less require a Smog Check. There are no model-year exceptions for diesel-powered vehicles.

• Gasoline-powered vehicles, hybrid vehicles, and alternative-fuel vehicles that are model-year 1975 and older.

• Gasoline-powered vehicles, hybrid vehicles, and alternative-fuel vehicles that are eight model years and newer do not require a biennial Smog Check.

• Gasoline-powered vehicles, hybrid vehicles, and alternative-fuel vehicles that are four model years and newer do not require a change-of-ownership Smog Check.

• Diesel-powered vehicles that are model-year 1997 and older.

• Diesel-powered vehicles with a gross vehicle weight rating of more than 14,000 pounds.

• Electric-powered vehicles.

• Motorcycles.

As per California law, the seller must have a Smog Check done on the vehicle and present the certificate of compliance to the buyer.

RVs and motor homes also require a Smog Check. These requirements are based on the type of vehicle model year.