California
For California, counties where testing is required is Alameda Butte Colusa Contra Costa Fresno Glenn Kern Kings Los Angeles Madera Marin Merced Monterey Napa Nevada Orange Sacramento San Benito San Francisco San Joaquin San Luis Obispo San Mateo Santa Barbara Santa Clara Santa Cruz Shasta Solano Stanislaus Sutter Tehama Tulare Ventura Yolo Yuba, verified against its source on 2026-08-19.
- State
- California our reading
- Counties where testing is required
- Alameda Butte Colusa Contra Costa Fresno Glenn Kern Kings Los Angeles Madera Marin Merced Monterey Napa Nevada Orange Sacramento San Benito San Francisco San Joaquin San Luis Obispo San Mateo Santa Barbara Santa Clara Santa Cruz Shasta Solano Stanislaus Sutter Tehama Tulare Ventura Yolo Yuba verified
- Vehicles covered / exempt
- Gasoline, hybrid, and alternative-fuel vehicles - model year 1976 and newer per bar.ca.gov
- Program / authority
- Smog Check Program per bar.ca.gov
- How often
- every other year to renew your vehicle registration per bar.ca.gov
Values marked our reading are our classification of what the source says — the source does not print them in those words. The quote below is the evidence for each one; judge it yourself.
What the source says
If you live in one of these counties, you need a smog inspection when you renew your vehicle registration. Alameda Butte Colusa Contra Costa Fresno Glenn Kern Kings Los Angeles Madera Marin Merced Monterey Napa Nevada Orange Sacramento San Benito San Francisco San Joaquin San Luis Obispo San Mateo Santa Barbara Santa Clara Santa Cruz Shasta Solano Stanislaus Sutter Tehama Tulare Ventura Yolo Yuba
— dmv.ca.gov, retrieved 2026-08-19
What bar.ca.gov says
Vehicles that need a Smog Check Gasoline, hybrid, and alternative-fuel vehicles - model year 1976 and newer Diesel vehicles - model year 1998 and newer
— bar.ca.gov, retrieved 2026-08-19
What bar.ca.gov says
A Smog Check is required every other year to renew your vehicle registration.
— bar.ca.gov, retrieved 2026-08-19
Sources
- dmv.ca.govhttps://www.dmv.ca.gov/portal/vehicle-registration/smog-inspections/
- bar.ca.govhttps://www.bar.ca.gov/consumer/smog-check-program
- bar.ca.govhttps://www.bar.ca.gov/consumer/smog-check-program