Emissions Test Checker
First, pick the state where your car is registered (and the county, if the state asks). Next, enter the model year and fuel type to find out if a test is required, how often, and what it costs.
Will my car pass the test?
Answer four quick questions about the battery, gas cap, and dashboard light, and you will see what to fix first.
What made my car fail the test?
Choose the message on your test report, or type in its code, and you'll see the likely cause and the price of a typical repair.
Does fixing it make sense?
Type in the cost of the repair and the car's value. In many states, you can still register the car if it keeps failing once you've spent a set amount on repairs. This permission is called a waiver. You'll see the amount and the first step to take.
Emissions test rules by state
An emissions test checks how much pollution comes out of your car. Three things decide if your car needs one: where it's registered, the model year, and which fuel it uses. Testing takes place in 27 states and Washington, D.C. in 2026; some states test in every county, while others cover only certain cities. Fully electric cars never need testing.
Do I need an emissions test?
If a gas car is registered somewhere that tests, it needs one. Most testing states also require one for a hybrid (a gas engine combined with an electric motor). Diesel cars are also tested in a few states. You don't need a test if the car is electric, still too new to be tested, or registered somewhere with no testing. The checker at the top gives you a plain yes or no.
The model year is printed on your registration card; it isn't the year you bought the car. For example:
- A 2012 gas car in Cobb County, Georgia, is tested every year, before the registration renewal deadline.
- Colorado tests only cars 2019 and older this year, so a 2022 gas car in Denver County, Colorado has no test due in 2026.
Emissions test rules by car age and fuel
Most states don't test a new car during its first few years, and the length of that wait varies by state. In Maryland, for example, a new car skips the test for its first 6 years, as long as it still has its first owner.
The type of fuel matters as well. Maryland doesn't test cars that run only on electricity or only on diesel. Some other states also skip testing for hybrids, classic cars, motor homes, and farm vehicles, according to the EPA, the federal clean-air agency. The rules for your car are listed on your state's page.
States that require emissions testing
Every state that tests has its own page; use the state list shown here to reach it. In many of those states, only certain counties or city areas are tested. Cars aren't tested in the other 23 states in 2026. Some of them ended a program years ago (Florida in 2000, Washington in 2020, Tennessee in 2022), and New Hampshire has paused its program. When your state isn't listed, check the states without testing.
One change is coming: from November 1, 2026, cars registered in Bexar County, Texas (the San Antonio area) must have the test. One may follow: Indiana has asked the EPA to let Lake and Porter counties stop testing. The EPA hasn't answered, so both counties still test.
What gets checked in an emissions test?
One of three checks applies to most cars:
- A parts check. Inspectors look for each part that cuts pollution and make sure none is missing or changed.
- A plug-in test for cars made in 1996 or later. These cars carry a computer, OBD (on-board diagnostics), which lights the check engine light when something is wrong. The inspector plugs a reader into it to see what it found.
- A tailpipe test, the usual check for older cars. A thin tube goes into the tailpipe (the pipe at the back of the car) to measure the exhaust, meaning the gases coming out.
Many states also check the gas cap, because a loose or cracked cap can let fumes escape. In Arizona, a car with the check engine light on fails on the spot.
Testing schedule
Most states test every 2 years. Georgia, New York and Texas are among those that test every year. Your state's page shows the schedule and fees.
Renewing your registration and emissions tests
Many states hold back your registration renewal until the car passes, and an expired registration means the car can't legally be driven. So it pays to test a little early. In Arizona, for example, a test counts if it's done up to 90 days before your registration expires. New Jersey lets you get tested up to 2 months ahead.
Answers to common emissions test questions
What is the emissions test for?
The test finds cars that pollute too much, so they get fixed. The federal Clean Air Act Amendments of 1990 made testing required in areas with badly polluted air. Failing is uncommon: in 2018, only about 1 in 20 cars failed the first time, and most passed once repaired.
Readiness monitors: what are they?
Your car's computer runs these self-checks on its own pollution parts as you're driving. During a plug-in test, the station checks whether they are complete. A trouble code is the short code the computer saves when it turns on the check engine light. Clearing one, or disconnecting the battery, starts these checks over, so a freshly repaired car can still fail. Usually about 200 miles of normal driving finishes them again. Our page on readiness monitors not ready explains more.
What is a catalytic converter for?
This exhaust part changes the most harmful gases into cleaner ones on their way to the tailpipe. A worn one sets off the check engine light, usually with code P0420, and the car then fails a plug-in test. Before you replace it, have a shop rule out cheaper causes: a leak in the exhaust pipe, or a bad oxygen sensor (a small part in the exhaust that measures how cleanly the engine burns). Read about the P0420 code.
What happens if my car fails?
The report you receive lists what failed. Get it repaired and retested before your state's deadline; in many states the first retest costs nothing. If you've spent your state's set amount on repairs and the car still fails, ask about a waiver. The tool for failed tests shows what the codes mean and what repairs usually cost.
What makes you pass an emissions test?
A plug-in test requires the check engine light to be off and every self-check complete. Tighten the gas cap until you hear a click. After a new battery, or after a shop has cleared the trouble codes, put about 200 miles on the car first so it can finish checking itself.