The California smog check guide

A smog check is an emissions inspection that checks whether your vehicle’s emissions-control system is working properly. It is also called a smog test, smog inspection or smog certification.

A smog check includes a visual inspection of emissions-control equipment, functional checks such as the check engine light, and an emissions test. Most 2000-and-newer vehicles are checked with the onboard computer (OBD-II). Older vehicles, generally 1999 and earlier, get a tailpipe test.

Most gasoline vehicles need a smog check every two years at registration renewal. You also need one when you sell a vehicle, when ownership changes or when you register a vehicle from out of state.

Smog checks are required for biennial registration renewal in many areas, change of ownership, and first-time California registration of a vehicle from another state.

A passing smog certificate is generally valid for 90 days for DMV registration purposes.

Exemptions generally include gasoline vehicles 1975 and older, fully electric vehicles, motorcycles, trailers, diesel vehicles 1997 and older, and heavy diesel vehicles over 14,000 lbs GVWR. Newer vehicles are also exempt for their first several model years and pay a smog abatement fee instead. Check your DMV renewal notice.

Hybrids are not automatically exempt. They follow the same rules as other gasoline vehicles, including the newer-vehicle exemption. Fully electric vehicles are exempt.

It is a fee the state charges at registration for newer vehicles that are exempt from a smog check. Your DMV renewal notice will list it.

No. A lit check engine light is an automatic failure. See our failed smog help page.

Make sure your check engine light is off, drive at least 15 minutes to warm up the engine, keep your emissions equipment stock, and avoid clearing codes or disconnecting the battery just before a test.

It varies by station and vehicle. See our prices and coupons page for Blaze Smog pricing, coming soon.

Not at Blaze Smog. Walk-ins are welcome Monday to Saturday, 8 AM to 5 PM.