California requires a smog check every two years for most vehicles, though the exact timing depends on when your vehicle was first registered and whether it has failed before.
Your smog check is due on the same month and year your vehicle registration expires. If your registration expires in June 2025, your smog check must happen before that date. You cannot renew your registration without a passing smog check, and you cannot get a smog check more than 30 days before your registration expires.
The two-year cycle resets each time you pass. If you fail, you can retest when ready at no additional cost at the same station, and you have until your registration expires to pass. Once you pass, your next check is due two years later.
Key Takeaways
- Your smog check is due in the same month your vehicle registration expires, which is typically every two years.
- You can schedule a smog check no earlier than 30 days before your registration expires.
- If you fail, you can retest at the same station when ready without paying again.
- Vehicles older than 1976 and some newer electric or hybrid vehicles are exempt from smog checks.
- You must have a passing smog check before you can renew your registration with the California Department of Motor Vehicles.
When your first smog check is due
If you register a vehicle in California for the first time, your first smog check is due when your initial registration expires. Most new registrations are valid for two years, so your first check is due two years from the registration date.
If you buy a used vehicle that is already registered in California, you inherit the previous owner's registration expiration date. You do not get a new two-year cycle. Your smog check is due on that same expiration month, whether that is three months away or 18 months away.
Vehicles that do not need a smog check
Vehicles manufactured before 1976 are permanently exempt. Vehicles registered as classic cars, street rods, or kit cars may also be exempt if they meet specific criteria, though they must still pass a smog check once when first registered in that category.
Most electric vehicles and some hybrid vehicles are exempt. Gasoline-only vehicles registered after a certain model year in some counties may have different requirements. Your registration paperwork will note if your vehicle is exempt. If you are unsure, call your local smog check station or the California Air Resources Board at 1-800-END-SMOG (1-800-363-7664) to confirm.
What happens if you miss your smog check important date
If your registration expires without a passing smog check, your vehicle registration becomes invalid. You cannot legally drive the vehicle on public roads. You also cannot renew your registration online or by mail — you must do so in person at a Department of Motor Vehicles office and bring proof of a passing smog check.
If you are caught driving with an expired registration, you face a fine. The fine amount varies but typically starts at $250 or more. Getting a smog check and renewing your registration as soon as possible stops the clock on penalties.
How to find a smog check station and schedule
California maintains a searchable database of certified smog check stations at smogcheck.ca.gov. You can search by zip code or city. Most stations are independent repair shops, some are part of larger chains, and a few are dealerships. Many stations accept walk-ins, but calling ahead to confirm hours and wait times is common practice.
The test itself takes 10 to 30 minutes. You will need your vehicle keys and your registration paperwork. The station will run your vehicle's emissions through a machine and provide a printed receipt. If you pass, the station sends the result electronically to the Department of Motor Vehicles, and you can renew your registration when ready. If you fail, ask the station what repairs are needed before you retest.
Cost and what to expect at the station
The smog check fee is set by the state and is the same at every station: $30.25 for a regular test or $36.25 for a two-speed idle test (used for some older vehicles). This fee covers only the test itself. If your vehicle fails and needs repairs, those repairs are separate and vary widely depending on what is wrong.
Some stations offer repair services on-site. Others do not. If a station recommends expensive repairs, you can take your vehicle to a different repair shop for a second opinion. You do not have to use the same station for repairs that you used for the initial test. Once repairs are complete, you can retest at any certified station.
Smog check requirements if you move or change registration
If you move to a different California county, your smog check requirements do not change. You still follow your original registration expiration date. Some counties have stricter emissions standards than others, but your vehicle's smog check history follows it.
If you move out of California and then move back, or if you let your registration lapse and re-register the same vehicle, you may need a smog check before registration is allowed, depending on how long the gap was. Contact your local Department of Motor Vehicles office to confirm what is required in your situation.
Frequently Asked Questions
Can I get a smog check more than 30 days early?
No. California law does not allow smog checks to be performed more than 30 days before your registration expires. If you schedule one earlier, the station will turn you away. Plan to schedule your check in the month your registration expires or the month before.
What if I fail my smog check?
You can retest at the same station at no charge. The station will tell you what emissions system repairs are needed. You have until your registration expires to pass. If repairs are expensive, you may want a second opinion from another mechanic before proceeding.
Do I need a smog check if I only drive my car occasionally?
Yes. Frequency of use does not matter. If your vehicle is registered in California and is not exempt, a smog check is required every two years on your registration expiration date, regardless of how often you drive it.
Can I renew my registration without a smog check?
No. The Department of Motor Vehicles will not process a registration renewal without proof of a passing smog check. You must have the smog check completed before you attempt to renew, whether you renew online, by mail, or in person.
What if my vehicle is registered in another state but I live in California?
You must register your vehicle in California within 20 days of establishing residency. Once registered in California, you follow California smog check rules. Contact your local Department of Motor Vehicles office for the registration transfer process.