Smog Check 101

Smog Check Requirements by Vehicle Type

California doesn't test every vehicle the same way. Here's how requirements differ depending on what you drive.

Standard passenger vehicles

Regular & STAR-directed vehicle testing for standard registration renewal or ownership transfer. This is the most common test — most vehicles fall here unless DMV has flagged something specific about your registration.

Hybrid & diesel vehicles

Specialized testing for hybrid and diesel vehicles, which follow their own inspection requirements. If you drive a hybrid or diesel, it's worth confirming with us ahead of time that the equipment and process match your vehicle — it's routine for us, but it's a different test than a standard gas engine.

Out-of-state vehicles

Bringing a vehicle into California? We handle out-of-state smog inspections required for registration. This applies whether you're relocating to California permanently or registering a vehicle you brought with you.

Gross polluters

STAR station testing for vehicles flagged as gross polluters or previously failed smog checks. This tier requires STAR-station testing specifically — see our gross polluter retest guide for what happens after a fail.

RVs, trucks & minivans

Larger vehicles welcome. We test RVs, trucks, and minivans in addition to passenger cars. Larger vehicles are welcome — the testing process is the same in principle, just sized for the vehicle.

Not sure which category applies to you?

Your DMV renewal notice specifies what's required, but if anything is unclear, call ahead and we'll help you figure it out before you make the trip.