Vehicles That Need A Smog Check

✔ Gasoline, hybrid, and alternative-fuel vehicles - model year 1976 and newer

✔ Diesel vehicles - model year 1998 and newer

RVs, motorhomes, collector cars, and government vehicles that meet the above criteria also need a Smog Check.

Vehicles That Do Not Need A Smog Check

✔ Gasoline, hybrid, and alternative-fuel vehicles - eight model years and newer (for vehicle registration renewal only)

✔ Gasoline, hybrid, and alternative-fuel vehicles - four model years and newer (for change of ownership only)

✔ Gasoline, hybrid, and alternative-fuel vehicles - model year 1975 and older

✔ Diesel vehicles - model year 1997 and older

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

✔ Electric vehicles

✔ Motorcycles

When A Smog Check Is required

Vehicle Registration Renewal

A Smog Check is required every other year to renew your vehicle registration. Check your DMV registration renewal notice for one of these messages:

✔ “Smog Certification Required”

✔ “Smog Certification Required at a STAR station”

Change Of Ownership

A Smog Check is required when a vehicle changes ownership.

✔ If you're selling your vehicle, a Smog Check is required before you sell it. Be sure to give the buyer a copy of the vehicle inspection report.

✔ If you're buying a vehicle from a private seller, it must have passed a Smog Check within the last 90 days. Ask the seller for a copy of the vehicle inspection report. You can also check the vehicle's inspection history online.

✔ If you're buying a vehicle from a dealership, it must have passed a Smog Check within the past two years.

✔ If a family member bought you a vehicle, a Smog Check is usually required. Transferring a vehicle between immediate family members does not require a Smog Check.

Registering A Vehicle For The First Time In California

A Smog Check is required to register a vehicle for the first time in California. This includes vehicles purchased or previously registered in another state. 

How To Prepare For A Smog Check

✔ Bring your DMV registration renewal notice, if available. This helps the station verify your vehicle information.

✔ If your vehicle's check engine light is on, get it repaired before your Smog Check. The check engine light indicates a problem with the vehicle's emissions system. A vehicle will not pass a Smog Check with the check engine light on.

✔ If you recently disconnected or replaced your battery, drive your vehicle for a week or two. This will allow the readiness monitors to reset before your Smog Check.

✔ If your vehicle's software is modified, restore it to the manufacturer's original settings. You may also restore it to a version approved by the California Air Resources Board. Modified or non-approved software will cause a vehicle to fail a Smog Check.

✔ Stations may offer a pretest (or pre-inspection). This may help identify potential issues before the official inspection. Stations must provide an estimate before performing this service.

What Happens During The Smog Inspection

A Smog Check may include:

✔ Visual inspection of the emissions control system

✔ Functional inspection of the emissions control system

✔ On-board diagnostic (OBD) system check (for most 2000 and newer model year vehicles)

✔ Tailpipe emissions test (for pre-2000 model year gasoline vehicles)