A STAR smog check is a California emissions inspection performed at a station that holds STAR certification from the Bureau of Automotive Repair (BAR). You need one when your DMV registration renewal notice says “Smog Certification Required at a STAR station.” If it says that, no other licensed smog shop can do the job, even though the test itself is identical to what you’d get anywhere else.
What a STAR Station Is
STAR certification is voluntary for shops, but the ones that earn it must meet ongoing performance standards. BAR audits them more closely than regular smog stations and tracks their pass/fail rates against statistical benchmarks. If a station falls short, BAR can suspend its certification.1Bureau of Automotive Repair. STAR Program FAQ
The inspection equipment and procedure are the same at a STAR station as at any licensed smog shop. What’s different is the oversight. Because of that extra scrutiny, BAR routes vehicles it considers most likely to be high emitters to STAR stations, which reduces the chance that a dirty car gets a questionable pass.
When You’re Required to Use One
Your DMV renewal notice is the deciding document. If it specifies a STAR station, only a STAR station can inspect your vehicle. If it just says “Smog Certification Required” without the STAR language, any licensed smog shop will do.
Several situations put you in the STAR-required category:
- Your vehicle fits a high-emitter profile. BAR flags vehicles whose smog check history or model characteristics suggest they’re more likely to produce excessive emissions. These “directed” vehicles must go to a STAR station regardless of where you are in the state.1Bureau of Automotive Repair. STAR Program FAQ
- Your vehicle was previously classified as a gross polluter. A badly failed smog check in the past routes all future inspections to STAR stations.
- You’re renewing a biennial registration and your notice specifies STAR.2Bureau of Automotive Repair. Smog Check – When You Need One and Whats Required
- You’re bringing a vehicle into California from out of state for the first time, if BAR flags it for STAR inspection.
If you fail at a STAR station, your retest also has to happen at a STAR station.2Bureau of Automotive Repair. Smog Check – When You Need One and Whats Required
Vehicles That Don’t Need a Smog Check at All
Before you hunt for a station, check whether your vehicle is exempt:
- Fully electric vehicles.
- Motorcycles.
- Gasoline, hybrid, and alternative-fuel vehicles eight model years old or newer. You pay a $25 annual smog abatement fee instead.
- Diesel vehicles model year 1997 and older.
For a change of ownership, vehicles less than four model years old are exempt and the buyer pays a smog transfer fee instead.3California Department of Motor Vehicles. Smog Inspections
How to Find a STAR Station
Not every smog shop carries STAR certification, so verify before you drive over. BAR’s online Auto Shop Locator lets you enter your location and filter by service type; choosing “STAR Inspection” narrows the results to certified stations only.4Bureau of Automotive Repair. Auto Shop Locator A quick call to confirm the station’s certification is still active is worth the 30 seconds, because a station can lose certification between visits.
Stations come in two flavors. Test-only stations do inspections and nothing else. Test-and-repair stations can diagnose and fix problems if you fail. Both are valid for the inspection itself.
What the Inspection Involves
The technician starts with a visual check of your emissions control components, confirming everything is in place and connected, and looking for visible exhaust smoke. For vehicles model year 1996 and newer, the main event is the On-Board Diagnostic (OBD) test. The technician connects to your car’s OBD-II port and checks that your check engine light functions properly, that the system reports no diagnostic trouble codes, and that enough readiness monitors have completed their self-checks.5California Code of Regulations. Cal Code Regs Tit 16 3340.42.2 – Test Methods and Standards for the On-Board Diagnostic Inspection
Older vehicles, generally pre-2000, may also get a tailpipe emissions test, sometimes on a dynamometer. The whole process usually takes about 30 minutes.
What Your Results Mean
If you pass, the station electronically transmits your smog certificate to the DMV. The certificate is valid for 90 days, so complete your registration renewal within that window.2Bureau of Automotive Repair. Smog Check – When You Need One and Whats Required
If you fail, the vehicle inspection report tells you exactly what went wrong. You’ll need to repair the emissions-related problems and return for a retest. Most stations offer a free retest within 90 days if you come back to the same location where you originally failed.
What It Costs
Smog check prices aren’t regulated and vary by station. BAR’s own data from February 2026 put the average inspection at a STAR test-only station at about $62, with STAR test-and-repair stations averaging around $70. Non-STAR stations fell in a similar range.6Bureau of Automotive Repair. Smog Check Executive Summary Report February 2026 Prices above $99 aren’t captured in BAR’s tracking, so stations in high-cost areas may run higher. Test-only stations tend to be a bit cheaper since they don’t carry the overhead of a full repair shop.
Help if Your Vehicle Fails
California’s Consumer Assistance Program (CAP) offers help in a few forms if your car can’t pass.
Repair Assistance
If you qualify, BAR will cover up to $1,450 in emissions-related repairs for vehicles model year 1996 and newer, or up to $1,100 for model years 1976 through 1995. Repairs must be done at a CAP-participating station.7Bureau of Automotive Repair. Apply for Repair Assistance – Consumer Assistance Program
Vehicle Retirement
If the car isn’t worth fixing, you can retire it for a cash payment:
- $2,000 if the vehicle failed its most recent smog check and you meet income eligibility.
- $1,500 if the vehicle had a completed smog check (pass or fail) within the last 180 days and you meet income eligibility.
- $1,350 if the vehicle failed its most recent smog check, with no income requirement.8Bureau of Automotive Repair. Retire Your Vehicle
Repair Cost Waiver
If you’ve spent at least $650 on emissions-related repairs and the car still can’t pass, you may qualify for a repair cost waiver that lets you register it anyway. Repairs covered by a manufacturer’s emissions warranty don’t count toward the threshold, and BAR adjusts the figure periodically based on the Consumer Price Index, so confirm the current limit before relying on it.9Legal Information Institute. Cal Code Regs Tit 16 3340.43 – Repair Cost Limit