The California Smog Check Program requires vehicles that were manufactured in 1976 or later to participate in the biennial (every two years) smog check program in participating counties. The program’s stated aim is to reduce air pollution from vehicles by ensuring that cars with excessive emissions are repaired in accordance with federal and state guidelines. With some exceptions, gas-powered vehicles that are six years old or newer are not required to participate; instead, these vehicles pay a smog abatement fee for the first 6 years in place of being required to pass a smog check. The six-year exception does not apply to nonresident (previously registered out-of-state) vehicles being registered in California for the first time, diesel vehicles 1998 model or newer and weighing 14,000 lbs or less, or specially constructed vehicles 1976 and newer.[3] The program is a joint effort between the California Air Resources Board, the California Bureau of Automotive Repair, and the California Department of Motor Vehicles.

A Smog Check is not required for electric, diesel powered manufactured before 1998 or weighing over 14,000 lbs, trailers, motorcycles, or gasoline powered vehicles 1975 or older.[4] In April 2015, hybrid vehicles became subject to smog check requirements.

Although vehicles 1975 and older are not required to get a smog check, owners of these vehicles must still ensure that their emissions systems are intact.

Anyone wishing to sell a vehicle that is over four years old must first have a smog check performed. It is the seller’s responsibility to get the smog certificate prior to the sale. If the vehicle is registered in California and was acquired from a spouse, domestic partner, sibling, child, parent, grandparent, or grandchild it is exempt.

Go on Top