Smog Check 101

How Often Do You Need a Smog Check in California?

Smog checks aren't on a fixed annual schedule for every driver — it depends on your vehicle's age, registration cycle, and whether ownership is changing.

The common triggers

• Biennial registration renewal — most vehicles need a smog check every other year as part of the standard DMV renewal cycle.
• Change of ownership — buying or selling a used vehicle in California typically requires a current smog certificate as part of the title transfer.
• Bringing a vehicle into California — Bringing a vehicle into California? We handle out-of-state smog inspections required for registration.
• STAR-directed retest — if DMV flags your vehicle, see our STAR station guide for what that means.

Vehicles that are typically exempt

Newer vehicles (generally within their first several model years) and some other categories are exempt from smog checks at renewal, though a smog certificate may still be required at change of ownership. DMV's registration renewal notice will always tell you exactly what's required for your specific vehicle — that notice is the authoritative source, not a general rule of thumb.

Special vehicle categories

We also test vehicles that fall outside the standard passenger-car cycle: Hybrid & Diesel, RVs, Trucks & Minivans, and Gross Polluter that need directed retesting.

DMV paperwork while you're here

In addition to smog checks, we process DMV registration services on-site, so you can knock out your smog check and your paperwork in one stop. That includes Registration Renewal, Title Transfer, and Duplicate Registration, Title & Lost Plates.