Guide Updated 2026-10-30
Do I need a smog check in California
Most gas and hybrid cars from model year 1976 on, and diesels from 1998 on that weigh 14,000 pounds or less, need a smog check in California, while electric cars, motorcycles and cars from 1975 and older do not.
The short answer
Most gasoline and hybrid cars from model year 1976 on need a California smog check. Most diesel cars and trucks from model year 1998 on need one too, as long as they weigh 14,000 pounds or less. Electric vehicles never need one. Motorcycles do not need one. Cars from 1975 and older do not need one.
Whether you need one this year comes down to three questions. What does the car run on? What model year is it? And what is happening to it right now, a registration renewal, a sale, or a first registration in California?
Quick check. Look at your DMV renewal notice. If it says "Smog Certification Required," you need a smog check before you can renew. If it says "Smog Certification Required at a STAR station," you need one at a STAR station. If it says nothing about smog, you can renew without one this time.
The rest of this guide walks through every case. Use the table below to find your vehicle first. Then read the section on the event you are facing.
Which vehicles need a smog check
The California Bureau of Automotive Repair, called BAR, runs the Smog Check program. The rules come from the Health and Safety Code and the Vehicle Code. DMV enforces them when you register a car. The table gives the plain version.
| Your vehicle | Smog check needed | Rule behind it |
|---|---|---|
| Gasoline car or truck, model year 1976 and newer | Yes | Covered by the Smog Check program |
| Gasoline car or truck, model year 1975 and older | No | Exempt by law |
| Hybrid, model year 1976 and newer | Yes | Hybrids joined the program in January 2015 |
| Diesel, model year 1998 and newer, 14,000 pounds GVWR or less | Yes | Diesels were added in 2010 |
| Diesel, model year 1997 and older | No | Exempt by law |
| Diesel over 14,000 pounds GVWR | No Smog Check, but Clean Truck Check applies | CARB runs the heavy truck program |
| Electric vehicle | No | Exempt by law |
| Motorcycle | No | Exempt until BAR adopts motorcycle test rules |
| Trailer | No | DMV lists trailers as not needing a smog inspection |
| Engine with two cylinders or fewer, or a two stroke engine | No | Listed in the BAR reference guide (rotary engines are not exempt) |
| Natural gas or propane vehicle over 14,000 pounds GVWR | No | Exempt until further notice |
| Motorhome or RV that meets the fuel and year rules | Yes | RVs follow the same rules as cars |
| Collector car, 35 model years old or more | Partly | Needs only the fuel cap and fuel leak checks, plus meeting exhaust standards |
| Any car registered in ZIP code 90704 (Avalon on Catalina Island) | No | Health and Safety Code section 44044 |
Two details trip people up. First, "hybrid" counts as covered. Hybrids were added to the program in January 2015, so a hybrid is tested like any other car of its age. Second, a diesel is covered only if it is model year 1998 or newer and weighs 14,000 pounds GVWR or less. GVWR means the maker's gross vehicle weight rating.
The three events that trigger a smog check
A car that is covered by the program does not get tested at random times. A smog check is tied to one of a few events.
1. Your registration renewal, in a biennial area
In areas that require biennial checks, you need a smog check every other year to renew your registration. Biennial means every two years. DMV lists 34 whole counties plus parts of 6 more. The area guide has the full county list and every ZIP code for the partial counties.
You do not have to wait until the last day. A test can be done at any time within 90 days before it is required. If you pass a smog check at a sale or a first registration, that certificate also covers you for the next six months, so you do not need a second biennial check in that window.
2. A change of ownership
When a covered car is sold, the seller must provide a valid smog certification. This applies in every county, not just biennial ones. A private party certificate has to be less than 90 days old. We cover the sale rules, the family transfer exceptions and dealer sales in the buying and selling guide.
3. First registration in California
If you bring a car from another state, or buy one that was last registered elsewhere, you need a California smog check before DMV will register it. Even a brand new car from another state can fall under this rule. See the moving to California guide for the steps.
4. A special order
BAR can also require a check on a car that would normally be exempt. This can happen if remote sensing shows the car likely fails or has been tampered with. It also applies to specially constructed cars such as kit cars, and to cars that were randomly picked for the program.
How often do you need a smog check
In biennial areas, the answer is every two years once your car is old enough. In change of ownership areas, the answer is only when you sell or first register the car in the state.
Newer cars skip the renewal check. A gas, hybrid or alternative fuel car that is eight model years old or newer does not need the biennial check. BAR gives a simple rule. Add 8 to the model year. A 2020 model year car needs its first renewal smog check in 2028. The exemptions by model year guide has a lookup table for every year.
The sale rule is different. A gas vehicle that is four model years old or newer does not need a smog check when it is sold. The buyer pays an $8 smog transfer fee to DMV instead. That means a car in its fifth to eighth year can need a check at sale even though it does not need one at renewal.
Diesel is different. BAR says there are no model year exceptions for diesel vehicles. A diesel car or truck under 14,000 pounds gets neither the eight year renewal pass nor the four year sale pass.
While a car is in its first eight model years, you pay a smog abatement fee with your registration instead. It is $20 a year for years one to six and $25 a year for years seven and eight. Our smog abatement fee guide explains the bill line by line.
What about electric cars, hybrids and diesels
Electric vehicles
Battery electric vehicles are exempt. Nothing comes out of a tailpipe, so there is nothing to test. DMV counted about 1.46 million battery electric vehicles in its end of 2024 fleet file, and none of them needs a smog check.
Hybrids
Hybrids are covered. A hybrid that is model year 1976 or newer follows the same age rules as a gas car. That means a new hybrid skips the renewal check for eight model years and pays the abatement fee instead. An older hybrid tests every two years in a biennial area. DMV counted about 1.76 million gasoline hybrids on California roads at the end of 2024.
Diesels
Diesel cars and trucks from model year 1998 up, at 14,000 pounds GVWR or less, need a smog check. Diesel testing began on January 1, 2010. Diesels get no new vehicle exemption at all. If your diesel truck weighs more than 14,000 pounds, you fall under the CARB Clean Truck Check program instead. That program tests heavy trucks twice a year and has its own fee.
Motorcycles and trailers
State law exempts motorcycles from smog checks until BAR sets test procedures for them. Trailers do not need a smog check either.
RVs and motorhomes
A motorhome that runs on gasoline and is model year 1976 or newer needs a smog check. A diesel motorhome follows the diesel rules. Government vehicles that meet the fuel and year rules need checks too.
Is there a military exemption
No. Active duty service members and veterans still need smog checks on California registered vehicles. The DMV smog page says so plainly.
One related rule is worth knowing. Federal law requires a smog inspection for a vehicle that is not registered in California but is driven in the state by active duty personnel. Each base enforces it, usually by asking for a passing report before it issues a base sticker. Ask your base vehicle registration office what it wants.
Collector cars, kit cars and other special cases
- Collector cars. A collector motor vehicle that is at least 35 model years old and insured as a collector car gets a lighter test. It must meet its exhaust standards and pass the fuel cap and liquid fuel leak checks.
- Specially constructed vehicles. Kit cars need a BAR Referee label. Without one, the car goes to a Smog Check Referee. After a full Referee pass, the label lets regular stations test it from then on.
- Fleet vehicles. Government fleets file an annual report and use a BAR file number. Government and private fleet vehicles cannot use the repair cost waiver or the state repair assistance program.
- Catalina Island. ZIP code 90704, Avalon, is exempt from smog requirements. It is the only exempt ZIP code in Los Angeles County.
- Cars exempt by age. A car that is exempt because it is new still gets tested if it is registering from another state, if it is specially constructed, if remote sensing flags it, or if it is randomly selected.
How many California cars need a smog check
DMV publishes a count of registered vehicles by ZIP code, model year and fuel. The latest file holds 31.14 million vehicles at the end of 2024. We sorted them into rough smog check groups.
Registered vehicles by smog check group, millions
About 32 percent of the fleet, or 9.97 million vehicles, sits in the newest eight model years and skips the renewal check. About 59 percent are older gas and hybrid cars, the group that tests every two years where the area requires it. Diesels are about 4 percent and electric or hydrogen vehicles about 5 percent.
That group split matters because BAR logged 11,275,981 initial smog checks in 2025. About 8.5 percent of them failed on the first try. The test volume has grown every year since 2019.
Initial smog checks per year, millions
How to find out for sure
- Read your renewal notice. It says whether a smog certification is required and whether it must come from a STAR station.
- Check your model year and fuel. Both are on your registration card.
- Add 8 to the model year. If the answer is later than this year, you skip the renewal check. If the car is diesel, ignore this step.
- Look up your smog history. BAR lets you check any car at bar.ca.gov/inspection. Results show from midnight the day after the test.
- Call if your address is wrong. The test area comes from the address DMV has on file. If a station says it cannot test your car, update your address with DMV or call the DCA Consumer Information Center at (800) 952-5210.
Once you know you need a test, the next question is price. See our smog check cost guide for BAR price data. To find a shop, use the station finder. If you were told your car must go to a STAR station, read the STAR station guide.
Be careful with anyone who offers a pass without testing your car. Read about illegal smog check stations before you hand over a dollar.
Questions people ask
Does my car need a smog check this year?
It does if your renewal notice says "Smog Certification Required," or if you are selling the car or registering it in California for the first time. Cars that are eight model years old or newer skip the renewal check. Add 8 to the model year to see when yours starts.
Do electric cars need a smog check in California?
No. Electric vehicles are exempt. Hybrids are not exempt and follow the same age rules as gas cars.
Do diesel trucks need a smog check?
Yes, if the model year is 1998 or newer and the truck weighs 14,000 pounds GVWR or less. Diesels get no new vehicle exemption. Heavier diesel trucks fall under the CARB Clean Truck Check program.
Do motorcycles need a smog check in California?
No. State law exempts motorcycles until BAR adopts test procedures for them. Trailers are also exempt.
Is there a military exemption for smog checks?
No. Active duty members and veterans still need smog checks on California registered vehicles. Active duty personnel who drive a car registered in another state may need a passing inspection report for a base sticker.
How often do I need a smog check?
Every two years to renew registration in a biennial area, once the car is older than eight model years. Anywhere in the state you also need one when you sell a covered car that is more than four model years old.
Do I need a smog check to sell my car?
Usually yes. The seller must give the buyer a valid smog certification, and a private party certificate must be less than 90 days old. Gas cars four model years old or newer are exempt, and the buyer pays an $8 transfer fee instead.
Can an exempt car still be sent for a smog check?
Yes. BAR can require a check on an exempt age car if remote sensing flags it, if it is registering from out of state, if it is specially constructed or if it is randomly selected.