California drivers can avoid a Smog Check only when their vehicle and registration event qualify for an official exemption or fee substitution. The rules differ for registration renewal, a sale or transfer, and a vehicle’s first registration in California; an out-of-state test or a vehicle’s age does not automatically exempt it.
Check the DMV renewal notice and the California Bureau of Automotive Repair (BAR) guidance for your vehicle. If a check is required, use a licensed station and address any failure with repairs or available assistance—not a device or workaround intended to defeat the inspection.
Which registration event applies?
| Situation | What the rules say | What to do |
|---|---|---|
| Biennial renewal | Subject vehicles generally need a Smog Check every other year. Qualifying gasoline, hybrid, and alternative-fuel vehicles eight model years old or newer are exempt from the inspection and pay a smog abatement fee instead. BAR gives a 2020 model-year vehicle as first needing a renewal check in 2028. | Check the renewal notice; it indicates whether a check is due and whether it must be at a STAR station. |
| Sale or ownership transfer | A seller generally must provide valid Smog Check certification. Qualifying vehicles four model years old or newer do not need an inspection for transfer but incur a smog transfer fee. An immediate-family transfer may also be exempt, subject to the applicable relationship and transaction rules. | Confirm the vehicle’s model year and whether the transfer qualifies. If a family member bought the car for the recipient without first titling it in their own name, an inspection is required. |
| First California registration | A Smog Check is required, including for a vehicle purchased or previously registered in another state. | Do not assume an out-of-state inspection or prior registration replaces California’s requirement. |
| Vehicle temporarily outside California | A vehicle located out of state may qualify for a temporary exemption from a biennial requirement through DMV form REG 5103. This is not a permanent exemption. | Follow the DMV application process and obtain and submit the required Smog Check certification after the vehicle returns. |
Vehicle types and age-based exemptions
BAR lists electric vehicles, motorcycles, gasoline, hybrid, and alternative-fuel vehicles from model year 1975 and older, diesel vehicles from model year 1997 and older, and diesel vehicles above 14,000 pounds GVWR among the vehicles exempt under its listed rules. DMV separately identifies natural-gas vehicles over 14,000 pounds. Because the exact category matters, check current BAR and DMV guidance rather than relying on a general claim about a vehicle’s age or fuel.
The eight-model-year renewal fee substitution applies to qualifying gasoline, hybrid, and alternative-fuel vehicles; BAR says there is no equivalent model-year exception for diesel vehicles. The four-model-year transfer fee substitution is a separate rule and should not be confused with the renewal rule.
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How to prepare if a check is due
- Read the DMV renewal notice to confirm whether a Smog Check is required and whether the vehicle is directed to a STAR station.
- Check for an illuminated check-engine light. BAR says a vehicle with that light on will not pass because it indicates an emissions-system problem.
- If the battery was recently disconnected or replaced, drive the vehicle for a week or two so its readiness monitors can reset, as BAR recommends.
- Keep emissions equipment and software compliant. Modified or unapproved software can cause a failure; BAR advises restoring the manufacturer’s original or CARB-approved settings.
- Choose a licensed station suited to your needs. Test-only stations inspect but do not repair; test-and-repair stations inspect and repair; repair-only stations repair but do not inspect. STAR stations meet higher performance standards and inspect vehicles directed to them.
An inspection may include visual and functional checks, an OBD system check for most 2000-and-newer vehicles, and a tailpipe test for pre-2000 vehicles. Station prices vary and are not regulated. BAR says the station must charge an $8.25 Smog Check certificate fee, provide an estimate, and receive authorization before beginning the inspection. A passing certificate is sent electronically to DMV and is valid for 90 days.
If your vehicle fails
Review the vehicle inspection report, make the necessary repairs, and arrange a retest. Do not clear a diagnostic code as a substitute for diagnosing and fixing the problem. BAR’s Consumer Assistance Program may offer eligible consumers repair assistance or vehicle retirement; eligibility includes vehicle ownership, registration, inspection failure, and no tampered emissions-control system.
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For an official locator and current program information, consult California BAR. For renewal notices, family-transfer details, and the temporary out-of-state process, consult the California DMV and its REG 5103 form.
Independent reader supportYour contribution helps us test, update, and keep practical guides available for everyone.FAQ
Do I have to get a Smog Check when I renew my registration?
Not always. Subject vehicles generally need a check every other year, but qualifying gasoline, hybrid, and alternative-fuel vehicles eight model years old or newer pay a smog abatement fee instead. Check your DMV renewal notice for your vehicle’s requirement.
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Does an out-of-state Smog Check exempt my car from California testing?
No, not for a first-time California registration: BAR says a check is required, including for vehicles bought or previously registered out of state. A vehicle temporarily located outside California may qualify for a temporary exemption from a biennial requirement through DMV form REG 5103, with certification due after it returns.
Is there a military exemption from the Smog Check?
No. DMV says active-duty military members and veterans still need an inspection when one is otherwise required.
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A family member gave me a car. Do I need a Smog Check?
An immediate-family transfer may not require a check for qualifying relationships, including a spouse, domestic partner, sibling, child, parent, grandparent, or grandchild. A special case applies if the family member bought the car for you without first titling it in their own name; DMV says an inspection is required. Confirm your circumstances with DMV.
What should I do if my car fails?
Use the inspection report to identify the problem, make the necessary repair, and retest. If you meet the requirements, BAR’s Consumer Assistance Program may offer repair assistance or vehicle retirement.
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