What you need to know about Los Angeles smog tests

Los Angeles requires a smog inspection (also called a smog check) every two years for most vehicles, or annually if your car is older than 1975 or was flagged for high emissions. The test measures what comes out of your tailpipe — nitrogen oxides, particulate matter, and hydrocarbons — against state limits set by the California Air Resources Board. You cannot register or renew your registration without a passing test result, and the inspection must happen within 30 days before you submit your registration renewal to the Department of Motor Vehicles.

The test itself takes about 10 to 15 minutes and costs between $30 and $70 depending on your vehicle type and the testing station. You do not need an appointment at most stations, though some require one. The station will plug a probe into your vehicle's diagnostic port (or tailpipe on older cars), run the engine under controlled conditions, and send the results electronically to the state. You get a printed receipt on the spot.

Key Takeaways

  • Los Angeles County requires a smog inspection every two years for most vehicles, with annual testing for cars older than 1975 or those that previously failed.
  • The inspection must occur within 30 days before you renew your vehicle registration with the DMV.
  • You can find authorized test stations through the California Bureau of Automotive Repair website or by searching "smog check near me" — any station with a Bureau number is legitimate.
  • If your vehicle fails, you have 30 days to repair it and retest at no additional charge at the same station, or you can take it elsewhere and pay again.
  • Vehicles registered outside California but driven in Los Angeles do not need a smog test unless they are being registered in California.

When your vehicle needs a smog inspection

Most passenger cars and light trucks in Los Angeles County need a smog test every two years. The test is due in the same month your registration expires — if your registration expires in June, your smog test must be completed by June 30 of that year. You can take the test up to 30 days early, so you could test in May if you wanted to get it done ahead of time.

Vehicles older than 1975 must be tested every year instead of every two years. If your vehicle failed a smog test in the past, you must test annually going forward until it passes. Diesel vehicles, motorcycles, and vehicles registered as classic cars have different rules — the Bureau of Automotive Repair website lists the specific requirements for each category.

New vehicles (current model year) are exempt from smog testing for the first six years of registration. After that, they follow the standard two-year cycle. If you buy a used car in California, the seller must provide proof of a passing smog test dated within 30 days of the sale, or the sale cannot be completed.

Finding an authorized smog test station

Any station that performs smog tests in California must be licensed by the Bureau of Automotive Repair and display a Bureau number on the storefront. You can search for stations on the Bureau's website at bar.ca.gov — enter your zip code and it will show all licensed stations near you, along with their hours and phone numbers. You can also search "smog check Los Angeles" or "smog test near me" in Google Maps and filter for stations with Bureau numbers.

Prices vary by station and vehicle type. A basic smog test for a 1996 or newer vehicle typically costs $30 to $50. Older vehicles or those requiring a tailpipe test (instead of an onboard diagnostic test) may cost $50 to $70. Some stations charge extra for trucks or vehicles with high mileage. Call ahead if price matters to you, or ask when you arrive.

You do not have to return to the same station for your next test — any licensed station will do. However, if your vehicle fails, you have the option to retest at the same station within 30 days at no charge. If you take it to a different station, you will pay the full test fee again.

What happens if your vehicle fails the smog test

If your vehicle fails, the testing station will give you a printed report showing which emissions exceeded the limit. You then have 30 days to repair the vehicle and retest. If you retest at the same station within 30 days, the retest is free. If you wait longer than 30 days or go to a different station, you pay the full test fee again.

Common reasons for failure include a faulty oxygen sensor, a loose or missing gas cap, a malfunctioning catalytic converter, or engine problems that trigger the check-engine light. A mechanic can read the diagnostic trouble codes from your vehicle's computer to pinpoint the issue. Some repairs are inexpensive (a gas cap might cost $15), while others are costly (a catalytic converter can run $400 to $1,200 depending on the vehicle).

If repair costs are high, you may be able to get help through the California Vehicle Repair information Program, which provides grants of up to $1,500 toward emissions-related repairs for low-income vehicle owners. You can find information about this program through the Bureau of Automotive Repair website or your local air quality management district office.

Registering your vehicle after a passing smog test

Once you have a passing smog test result, you can renew your vehicle registration with the California DMV. The testing station sends the result electronically to the state, so you do not need to print anything or bring paperwork to the DMV. You can renew online at dmv.ca.gov, by mail, or in person at a DMV office.

The smog test result is valid for 30 days before your registration expires and 30 days after. If you test too early (more than 30 days before expiration), the result will not be accepted and you will need to test again. If your registration has already expired, you cannot legally drive the vehicle until you renew it, even if you have a passing smog test.

Registration renewal costs vary by vehicle type and county. Los Angeles County charges a base registration fee plus smog abatement fees. You can estimate your renewal cost on the DMV website before you pay.

Special situations and exemptions

Vehicles with a "gross vehicle weight rating" over 14,000 pounds (most full-size trucks and commercial vehicles) are exempt from smog testing in California. Electric vehicles and hydrogen fuel cell vehicles are also exempt. Motorcycles have their own testing rules and are handled separately from cars and trucks.

If you are a military member stationed in California, you may be able to defer registration renewal while deployed. If you are a disabled veteran, you may may have access to for a reduced registration fee. Contact your local DMV office or visit dmv.ca.gov for details on these programs.

If you own a vehicle registered outside California but drive it in Los Angeles, you do not need a California smog test unless you are registering it in California. However, your home state may have its own emissions testing requirements.

Frequently Asked Questions

Can I drive my car if it fails the smog test?

Yes, you can drive it while you arrange repairs and schedule a retest. However, you cannot renew your registration until you have a passing test result. If your registration expires before you pass the test, you cannot legally drive the vehicle.

What if I just moved to Los Angeles and my car is registered in another state?

You have 20 days after establishing residency in California to register your vehicle in California. Once you do, you will need a passing smog test within 30 days before or after your registration renewal date. If your vehicle is newer than 1975 and has not been in California long, you may be exempt from testing for the first six years.

Do I need a smog test if I am selling my car?

Yes, the seller must provide a passing smog test dated within 30 days of the sale. If the test is older than 30 days, the buyer must get a new test before the sale can be completed. This protects the buyer from inheriting a vehicle with emissions problems.

How long does it take to get smog test results?

Results are available when ready after the test. The testing station prints a receipt on the spot and sends the result electronically to the state within minutes. You can then renew your registration right away if your registration has not expired.

What if my vehicle has a check-engine light on?

Many stations will not test a vehicle with an active check-engine light because it usually indicates an emissions problem that will cause a failure. Have a mechanic read the diagnostic code first. Once the problem is fixed and the light is off, you can retest.