A STAR station is a California-certified repair shop that can test your vehicle and fix smog failures on the same visit

When you fail a smog check in California, you have two choices: take your car to any test station for a retest after repairs, or go to a STAR (Smog Test And Repair) station that can do both the testing and the repairs in one place. STAR stations are privately owned repair shops licensed by the California Bureau of Automotive Repair. They follow the same testing rules as regular test-only stations, but they also hold a repair license, so they can fix the problems that caused your failure.

The main advantage is convenience — you do not have to drive to one shop for diagnosis, then to another for repairs, then back to a third for a retest. The main disadvantage is that STAR stations have a financial incentive to recommend repairs, so you should understand what you are paying for and get a second opinion if the bill seems high or the repairs seem extensive.

Key Takeaways

  • STAR stations are repair shops licensed to both test and repair vehicles for smog compliance, and you can get both services at one location.
  • You can use a STAR station only after you have already failed a smog check; you cannot use one for your initial smog test.
  • STAR stations charge a testing fee (usually $30 to $50) and then charge separately for any repairs they recommend.
  • The Bureau of Automotive Repair maintains a searchable database of licensed STAR stations by county and city on its website.
  • You should always get a written repair estimate before authorizing work, and you can seek a second opinion at another shop if the estimate seems high.

When you can and cannot use a STAR station

You can only use a STAR station for a retest after you have failed a smog check at a regular test-only station. You cannot use a STAR station for your initial smog test — that must happen at a test-only station or a STAR station operating in test-only mode. This rule exists to prevent conflicts of interest: if STAR stations could perform initial tests, they would profit from finding failures that may not be real.

Once you have a failed test in hand, you can take your vehicle to any STAR station in California, not just one in your county. The station will perform the same smog test again and, if your vehicle still fails, will recommend repairs. If your vehicle passes the retest, you are done — you pay only the test fee and can register your vehicle.

How to find a STAR station near you

The California Bureau of Automotive Repair maintains a searchable database of all licensed STAR stations at bar.ca.gov. Go to the "STAR Program" section and use the station locator tool. You can search by county, city, or ZIP code. The database shows each station's address, phone number, hours, and whether it is currently licensed.

You can also call your local smog test station and ask for STAR station referrals in your area. Many test-only stations keep a list of nearby repair shops. If you already have a mechanic you trust, call them and ask whether they hold a STAR license — many independent shops do.

When you call a STAR station to schedule a retest, tell them you have a failed smog test and ask what documents to bring. Most will ask for your vehicle registration, proof of insurance, and the failed test report itself. Some stations book appointments; others take walk-ins. Ask about wait times and whether you should call ahead.

What to expect during a STAR station retest

The retest process is identical to the initial smog test: the technician will connect your vehicle to a dynamometer (a machine that measures emissions) and run the same test sequence. The test takes about 10 to 15 minutes. If your vehicle passes, you receive a passing certificate and can register it when ready. If it fails again, the technician will print a report showing which emissions standards your vehicle did not meet.

At this point, the STAR station will recommend repairs. They are required by law to provide a written estimate before they begin any work. Read the estimate carefully and ask questions about any repair you do not understand. Common smog-related repairs include oxygen sensor replacement, catalytic converter repair or replacement, and fuel system cleaning. Costs vary widely depending on what needs fixing.

You are not required to have repairs done at the STAR station where you tested. You can take the failed test report and the repair estimate to another shop for a second opinion, or you can do the repairs yourself if you have the skills. Once repairs are complete at any shop, you can return to any test station (STAR or test-only) for a retest.

Understanding STAR station fees and repair costs

STAR stations charge a test fee for the retest, typically between $30 and $50. This fee is separate from any repair costs. The test fee is non-refundable even if you do not authorize repairs. Repair costs depend entirely on what your vehicle needs and can range from under $100 for a sensor replacement to over $1,000 for a catalytic converter or transmission work.

Before you authorize any repair, ask the STAR station for an itemized written estimate that lists each repair, the parts cost, the labor cost, and the total. California law requires this. If the estimate seems high, you have the right to take your vehicle elsewhere. Some STAR stations will also perform a free or low-cost diagnostic scan to identify the problem before quoting a repair price.

Keep in mind that STAR stations profit from repairs, so they have an incentive to recommend more work than may be strictly necessary. If a station recommends extensive repairs for a vehicle that is only slightly out of compliance, getting a second opinion from an independent mechanic is reasonable and often worth the cost.

What happens after repairs are completed

Once you have had repairs done — whether at the STAR station or elsewhere — you can take your vehicle to any smog test station for a retest. You do not have to return to the same STAR station. Bring your vehicle registration, proof of insurance, and the failed test report from your initial test. The new test will cost the standard test fee, usually $30 to $50.

If your vehicle passes the retest, you will receive a passing certificate. Take this certificate to the California Department of Motor Vehicles (DMV) along with your vehicle registration to complete your registration. If your vehicle fails again, you will need to identify what repairs are still needed and repeat the process.

California gives you 30 days from the date of your initial failed test to get a passing retest. If you do not pass within 30 days, you will need to start over with a new initial smog test, which will cost another test fee. This is why it makes sense to get repairs done promptly once you know what is wrong.

Choosing between a STAR station and a test-only station for your retest

If you have already identified the problem and had repairs done elsewhere, a test-only station is usually cheaper and faster — you pay only the test fee with no repair markup. If you are unsure what repairs you need and want everything handled in one place, a STAR station offers convenience, though you will pay more for that convenience and should watch for unnecessary upsells.

A middle ground is to take your failed test to an independent mechanic you trust, get a diagnosis and estimate, and then decide whether to have repairs done there or at a STAR station. Many independent shops are STAR-licensed and can handle both diagnosis and repairs without the pressure to sell you work you do not need.

Frequently Asked Questions

Can I use a STAR station for my first smog test?

No. STAR stations can only perform retests after you have failed an initial smog test at a test-only station. Your first smog test must be done at a test-only station or at a STAR station operating in test-only mode. This rule prevents conflicts of interest.

What if I get repairs done at a STAR station and my vehicle still fails the retest?

You can take your vehicle back to the same STAR station and ask them to diagnose why it still failed. They should perform additional diagnostics at no charge if the repairs they recommended did not fix the problem. If you are not confident in their diagnosis, you can seek a second opinion at another shop.

How long does it take to get repairs done at a STAR station?

It depends on the repair. straightforward repairs like an oxygen sensor replacement might take an hour or two. More complex work like catalytic converter replacement can take a full day or longer. Call ahead and ask for an estimate of how long the work will take before you drop off your vehicle.

Do I have to use the STAR station's recommended repairs, or can I shop around?

You can shop around. The STAR station must give you a written estimate, but you are not obligated to accept it. You can take that estimate to another mechanic for a second opinion, or you can do the repairs yourself if you have the skills. You can then return to any test station for a retest.

What if a STAR station charges me a test fee but will not do repairs?

The test fee is separate from repair services. If your vehicle passes the retest, you pay only the test fee and you are done. If it fails and you decide not to have repairs done there, you still owe the test fee. This is why it is worth calling ahead to understand the station's policies.