The California smog check guide

A smog check is an emissions inspection that confirms your vehicle’s pollution-control system is present and working. It is also called a smog test, smog inspection or smog certification.

Check your DMV renewal notice first. It says whether a smog check is required. In general you need one every two years at registration renewal, when you sell or buy a vehicle, and when you register a vehicle in California for the first time.

Most gasoline, hybrid and diesel vehicles need one every two years when you renew your registration. Gasoline vehicles that are 8 model years old or newer skip the renewal smog check and pay a smog abatement fee instead.

Gasoline, hybrid and alternative-fuel vehicles from model year 1976 and newer are covered, and diesel vehicles from 1998 and newer that weigh 14,000 lbs GVWR or less. Vehicles 1975 and older, and diesels 1997 and older, are exempt.

For a gasoline vehicle, add eight to the model year. A 2020 model-year vehicle, for example, needs its first renewal smog check in 2028. Your DMV renewal notice always has the final word.

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

A passing smog certificate is sent electronically to the DMV and is valid for 90 days, so avoid testing too early.

Exemptions include gasoline vehicles 1975 and older, diesels 1997 and older, diesels over 14,000 lbs GVWR, fully electric vehicles, motorcycles and trailers. Newer gasoline vehicles are also exempt for a set number of model years (see the details above).

Usually yes. A change of ownership normally needs a passing smog certificate, and the seller is generally responsible for providing it. Gasoline vehicles that are 4 model years old or newer are exempt and pay a smog transfer fee to the DMV instead.

Transferring a vehicle between immediate family members does not require a smog check. The DMV lists exactly who counts, so confirm with them before you transfer.

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

Diesels from 1998 and newer that weigh 14,000 lbs GVWR or less do, and there is no newer-model-year exemption for diesels. See our diesel smog check page.

A vehicle coming from another state normally needs a passing smog check before California will register it for the first time. See our out-of-state smog check page.

It is a fee charged with your registration for newer gasoline vehicles that skip the renewal smog check. Your DMV renewal notice lists the amount.

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

You get a report showing why. After repairs, come back for a retest. A few vehicles with very high emissions can be sent to a Test-Only station or the state referee, and your DMV paperwork will say so.

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.