A STAR certified smog check is performed by a testing station that has met California's standards for equipment, training, and record-keeping

Not every smog check station is the same. California's STAR (Smog Check Test And Repair) program certifies stations that use properly calibrated equipment, employ trained technicians, and follow strict protocols for testing and reporting results. When you take your vehicle to a STAR-certified station, you know the test meets state standards — and the results are accepted by the California Department of Motor Vehicles (DMV) without question.

The difference matters because non-certified stations exist, and their test results can be challenged or rejected by the DMV. A STAR-certified station gives you one less thing to worry about: the test itself is legitimate, and you won't have to retest somewhere else because the first result wasn't accepted.

Key Takeaways

  • STAR-certified stations use equipment that California has verified and calibrated, and their technicians have completed required training.
  • You can find STAR-certified stations through the California Bureau of Automotive Repair website or by searching your city and "STAR smog check".
  • A test at a STAR station costs the same as a non-certified station, but the result is accepted by the DMV without further verification.
  • STAR stations must report your test results directly to the state, so you do not have to submit paperwork yourself.

How STAR certification works

The California Bureau of Automotive Repair (BAR) oversees the STAR program. To become certified, a smog check station must meet equipment standards, pass inspections, and keep detailed records of every test performed. Technicians must complete training and pass an exam. The station's equipment is checked regularly to may support it stays calibrated.

Once certified, a station displays a STAR decal and is listed in the BAR's online directory. The certification is not permanent — stations must renew it and continue meeting standards. If a station fails an inspection or violates rules, it can lose its certification.

Finding a STAR-certified station near you

The California Bureau of Automotive Repair maintains a searchable list of all certified stations on its website. You can search by city, zip code, or station name. The list shows the station's address, phone number, and hours. Many stations also advertise their STAR certification on Google Maps and their own websites.

You can also call your local city or county environmental office — they often have a list of nearby certified stations. Some areas have more certified stations than others, so if you live in a rural area, you may need to travel farther than someone in a city.

What happens during a STAR smog check

The test itself is the same whether you go to a STAR station or a non-certified one. The technician connects your vehicle to a dynamometer (a machine that measures emissions) or uses a probe to read your vehicle's onboard diagnostic system, depending on your vehicle's year and type. The test takes 10 to 30 minutes.

At a STAR station, the technician enters the results into a state database when ready. You receive a printed receipt, and the DMV receives the results electronically. If your vehicle passes, you can renew your registration right away. If it fails, you have 30 days to repair it and retest.

Cost and timing

A STAR smog check costs between $30 and $70, depending on your vehicle type and the station's location. The price is set by the station, not by the state, so you can call ahead to compare. The test itself takes 10 to 30 minutes, and you usually have your results before you leave.

Many stations are busy during peak times — the last few weeks before registration expires, or the last day of the month. If you schedule an appointment or go early in the day, you may wait less time. Some stations offer online scheduling.

STAR stations versus non-certified stations

Non-certified stations can perform smog checks, but their results are subject to verification by the DMV. This means the DMV may ask for additional proof or require you to retest at a certified station. A STAR result is accepted when ready, with no extra steps.

Non-certified stations may charge less, but the savings disappear if you have to retest. For most people, going to a STAR station the first time saves time and money overall. The only reason to use a non-certified station is if no STAR station is reasonably close to you.

What to bring to your smog check

Bring your vehicle registration or proof of ownership, your driver's license, and your vehicle keys. The technician will need to access your vehicle's information and may need to start the engine. If your vehicle is registered out of state, bring documentation showing you now live in California.

Make sure your vehicle's check engine light is off before you go. If the light is on, your vehicle will fail the test automatically, and you will have to repair the problem and retest. A technician can sometimes read the code for you, but they are not required to help diagnose the issue.

Frequently Asked Questions

Can I use a non-certified station and still pass the DMV?

Yes, but the DMV may verify your results or ask you to retest. A STAR result is accepted without question. If you use a non-certified station and the DMV rejects your result, you will have to pay for another test at a certified station.

What if my vehicle fails the smog check?

You have 30 days to repair the problem and retest. You can retest at the same station or a different one. Keep your repair receipts — some programs offer rebates or information if you need to repair an older vehicle to pass emissions standards.

Do I need an appointment at a STAR station?

Most stations accept walk-ins, but calling ahead or booking online can save you time, especially during busy periods. Check the station's website or call to see if they take appointments.

How long does a STAR certification last?

Stations must renew their certification regularly and pass inspections to keep it. You do not need to worry about this — the BAR handles oversight. If a station loses its certification, it will no longer appear in the official directory.

Can I get my smog check results online?

STAR stations report results to the state database, and you can view your results through the DMV website using your vehicle registration number. You also receive a printed receipt at the station.