The STAR program is California's way of letting some vehicles skip smog checks entirely

The STAR (Smog Test Abatement and Retrofit) program is run by the California Air Resources Board and allows certain vehicles to be exempt from the biennial smog inspection that most California cars need. If your vehicle qualifies, you do not have to pay for a smog check or visit a testing station — you straightforward renew your registration without the test.

The program targets vehicles that are already very clean: newer cars with low mileage, vehicles that have passed multiple consecutive smog checks, or cars that have been retrofitted with approved emissions equipment. The goal is to reduce unnecessary testing for vehicles that pose almost no risk of failing.

STAR status is not something you request separately. The California Department of Motor Vehicles (DMV) determines your vehicle's may be able to access automatically when you renew your registration. If your car qualifies, the DMV will tell you during the renewal process.

Key Takeaways

  • STAR exemption is assigned by the DMV based on your vehicle's age, mileage, and smog check history — you do not need to do anything to request it.
  • Vehicles with fewer than 6,000 miles per year on average, or those that have passed four consecutive smog checks, are the most common candidates for STAR status.
  • If your vehicle is STAR-exempt, your registration renewal notice will say so, and you can skip the smog check that year.
  • STAR status can change from year to year depending on your vehicle's mileage and test results, so check your renewal notice each time.

Which vehicles typically may have access to for STAR exemption

The DMV uses several criteria to decide whether a vehicle gets STAR status. The most common path is low annual mileage: if your vehicle averages 6,000 miles per year or fewer, you are a strong candidate. This is calculated based on the mileage reported at your last registration renewal and the current odometer reading.

Vehicles that have passed four or more consecutive biennial smog checks without any failures also may have access to. This track record shows the car is consistently clean, so the state sees little reason to test it again. Some vehicles that have been retrofitted with approved emissions control equipment may also be exempt.

Newer vehicles — typically those less than four model years old — are often STAR-exempt as well, since they have stricter factory emissions standards and are less likely to fail. However, age alone does not may provide exemption; the DMV looks at the full picture of mileage and history.

How the DMV determines and notifies you of STAR status

You do not explore for STAR or take any action to receive it. The DMV's computer system reviews your vehicle record when you renew your registration and automatically assigns STAR status if your car meets the criteria. This happens behind the scenes during the renewal process.

When you receive your registration renewal notice in the mail, it will clearly state whether your vehicle is STAR-exempt for that renewal period. If it says your vehicle is exempt, you can proceed with registration renewal without obtaining a smog certificate. If it does not mention STAR exemption, you will need to get a smog check before you can renew.

The renewal notice is the official notification. You do not need to contact the DMV or do anything extra — just read the notice carefully to see whether the smog check requirement is listed.

What happens if your vehicle loses STAR status

STAR exemption is not permanent. Your vehicle's status is re-evaluated every time you renew your registration, usually every two years. If your mileage has increased significantly, or if your vehicle fails a smog check in the meantime, you may lose the exemption and be required to test again at your next renewal.

For example, if you were STAR-exempt because you drove fewer than 6,000 miles per year, but you then drove 8,000 miles in the next two years, the DMV may remove your exemption. Similarly, if you had to get a smog check for some reason and your vehicle failed, that failure can disqualify you from STAR status going forward.

When you lose STAR status, your renewal notice will show that a smog check is required again. There is no appeal process for STAR decisions — the DMV's information is based on the mileage and test data in your file.

STAR exemption versus failing a smog check

STAR exemption and smog check results are separate things. Being STAR-exempt means you do not have to test. But if you do get a smog check for any reason — perhaps you are selling the car, or you want to verify it is clean — and it fails, that failure goes on your record and can affect your future STAR may be able to access.

Conversely, if you are not STAR-exempt and you fail a smog check, you have options: you can repair the vehicle and retest, or you can pursue a Smog Check Abatement (SCA) certificate, which allows registration even after a failure if repairs are too expensive. STAR status does not change these rules; it straightforward means you do not have to test in the first place.

The key point is that STAR is about avoiding the test, not about what happens if you take it. The two systems operate independently.

Checking your STAR status before renewal

You can check your vehicle's STAR status through the California DMV website or by calling the DMV directly. The easiest method is to log into your DMV online account if you have one, or to visit the DMV's vehicle registration page and enter your license plate number.

You can also call the DMV at 1-800-777-0133 and provide your vehicle identification number (VIN) or license plate. A representative can tell you whether your vehicle is currently STAR-exempt and whether you will need a smog check at your next renewal.

Checking early — several months before your registration expires — gives you time to plan. If you are not STAR-exempt and you need a smog check, you can schedule it with a testing station at your convenience rather than waiting until the last minute.

What to do if your vehicle is not STAR-exempt

If your vehicle does not may have access to for STAR exemption, you will need to obtain a smog certificate before you renew your registration. You can visit any Bureau of Automotive Repair (BAR)-certified smog testing station. These stations are located throughout California and are listed on the BAR website.

The smog check itself costs money — the state sets a maximum fee, but the exact price varies by station and by vehicle type. Bring your vehicle registration and proof of ownership. The test usually takes 30 minutes to an hour.

If your vehicle passes, you will receive a smog certificate that you can use to renew your registration online, by mail, or in person at the DMV. If it fails, you will need to repair the vehicle and retest, or pursue other options like the Smog Check Abatement program.

Frequently Asked Questions

Can I renew my registration online if I have STAR exemption?

Yes. If your vehicle is STAR-exempt, you can renew your registration entirely online through the DMV website without visiting an office or obtaining a smog certificate. Your renewal notice will confirm that no smog check is required.

Does STAR exemption mean my car will never fail a smog check?

No. STAR exemption means you do not have to test, but it does not may provide your vehicle would pass if tested. The exemption is based on mileage and history, not on a current test result. If you do get a smog check and fail, you will need to repair the vehicle.

What if I disagree with the DMV's decision that my vehicle is not STAR-exempt?

The DMV's information is based on your vehicle's mileage and smog check record, which are objective data. If you believe there is an error in your file — for example, if the mileage was recorded incorrectly — you can contact the DMV with documentation. Otherwise, there is no formal appeal process for STAR decisions.

If I buy a used car, does it keep the previous owner's STAR status?

No. STAR status is tied to the vehicle's record, not the owner. When you register the car in your name, the DMV will re-evaluate its status based on the mileage and history in the system. You may have a different STAR status than the previous owner did.

Can I get STAR exemption if I just moved to California?

STAR status depends on your vehicle's California registration history and mileage record. If you are new to California, your vehicle may not have enough history to may have access to when ready. After you register your vehicle in California and establish a record, you may become STAR-exempt at a future renewal.