Smog Check

What is a smog check?

Smog checks or tests, or emission checks or tests, is a test of your vehicle's engine emissions. The United States Environmental Protection Agency (EPA) regulates air emissions from stationary and mobile sources (e.g., motor vehicles). EPA is able to do this through the Clean Air Act. The Clean Air Act allows EPA to establish air quality standards that help protect the health of the public by regulating dangerous air pollutants.

Can I pass a smog check if my Check Engine Light is on?

There are several reasons your vehicle's Check Engine Light may turn on or flash. It could mean something simple like your gas cap is loose or that it's time for an oil change. It may also turn on for something more serious, such as a bad catalytic converter. That's not a good sign. The catalytic converter helps reduce air pollution and harmful emissions coming from your vehicle. It converts dangerous carbon monoxide into harmless carbon dioxide.

If your Check Engine Light is on, you're probably not going to pass a smog check. You can check your own light at home if you have an OBD-II reader, which will tell you why your Check Engine Light is on. If you do not have a reader, you can take your vehicle into your favorite auto repair shop to diagnose the problem.

Does my state require smog checks?

Smog check requirements vary depending on how old your vehicle is and what area of the country you live in. Smog checks are often required every two years, or whenever you have to register a new vehicle, or renew your vehicle's registration. Let's take a look at the smog check requirements in each state.

Smog Check Requirements in Alabama

Although not required in this state, it's a good idea to ensure that your car passes its emissions tests.

Smog Check Requirements in Alaska

Although not required in this state, it's a good idea to ensure that your car passes its emissions tests.

Smog Check Requirements in Arizona

Arizona vehicles are required to pass a smog test every two years in the Phoenix and Tucson metro areas only.

Smog Check Requirements in Arkansas

Although not required in this state, it's a good idea to ensure that your car passes its emissions tests.

Smog Check Requirements in California

Most vehicles in California must pass a smog inspection in order register a new car, or renew your vehicle's registration. Exceptions to this law include:

• Your vehicle is gasoline-powered and is a 1975 model or older, including trailers and motorcycles.
• Your vehicle is diesel-powered and is a 1997 model or older, or it has a Gross Vehicle Weight over 14,000 pounds.
• The vehicle is electric.
• Your vehicle is under 8 model-years old and is gasoline-powered.
• Your vehicle weighs more than 14,000 pounds and is powered by natural gas.

You are not allowed to disconnect, alter or modify a smog control device on your vehicle. If you take your vehicle in for a smog check and it fails, you are not allowed to drive the vehicle until the smog control device has been repaired and the vehicle passes another smog check. (VC 27156)

For vehicles under 4 model-years old, you can pay a smog abatement fee that waves your smog inspection for the first 8 years of your vehicle's registration.

Smog Check Requirements in Colorado

Certain vehicles are required to pass a smog check every two years in the following counties:

• Boulder
• Broomfield
• Denver
• Douglas
• Jefferson

Parts of Adams, Arapahoe, Larimer, and Weld counties also require a smog check every two years. Vehicles 7 model-years and newer are not required to have a smog check.

Smog Check Requirements in Connecticut

Connecticut vehicles are required to pass an emissions test every two years. You'll get an official notice in the mail at least 45 days before your emissions test is required.

Smog Check Requirements in Delaware

Vehicles in Delaware must pass an emissions test if the vehicle weighs 8,500 pounds or less. Vehicles manufactured before 1968, motorcycles, and diesel-fueled vehicles manufactured before 1997 are not required to get an emissions test.

Emissions testing in Delaware is required every two years, depending on your vehicle's model year and how long it's been registered in Delaware. Vehicles within their first 7 model years do not have to get tested.

Smog Check Requirements in Florida

Although not required in this state, it's a good idea to ensure that your car passes its emissions tests.

Smog Check Requirements in Georgia

Emissions testing is not required in Georgia for vehicles for vehicles within the last 3 model years, vehicles that are 25 model years or older, motorcycles, RVs, motor homes, and diesel-powered vehicles.

Emissions tests in Georgia are only required annually for gasoline-powered cars and trucks 8,500 pounds and under in the 13 metro Atlanta counties:

• Cherokee
• Clayton
• Cobb
• Coweta
• DeKalb
• Douglas
• Fayette
• Forsyth
• Fulton
• Gwinnett
• Henry
• Paulding
• Rockdalte

Smog Check Requirements in Hawaii

Although not required in this state, it's a good idea to ensure that your car passes its emissions tests.

Smog Check Requirements in Idaho

Emissions testing is required in Idaho in areas of the state where motor vehicles emissions are one of the top two sources of pollution. This includes Ada and Clayton county.

Smog Check Requirements in Illinois

Certain vehicles in various areas of the state must pass an Illinois Environmental Protection Agency (IEPA) emissions test in order to renew the vehicle’s registration. The IEPA will notify owners of the scheduled test month and year for their vehicle. Emissions testing is required in the following counties: Cook, DuPage, Lake, and parts of Kane, Kendall, McHenry, Will, Madison, Monroe, and St. Clair.

Smog Check Requirements in Indiana

While Indiana doesn’t require a full vehicle inspection in order to renew your registration, you may be required to pass an emissions test. Vehicles registered in Lake and Porter counties are required to undergo emissions tests and tampering inspections every two years if the vehicle was manufactured after 1976 and has a gross vehicle weight rating of 9,000 pounds or less. If your vehicle falls into those categories, you’ll need to visit a Clean Air Check testing station and pass an inspection in order to register or renew your registration.

Smog Check Requirements in Iowa

Although not required in this state, it's a good idea to ensure that your car passes its emissions tests.

Smog Check Requirements in Kansas

Although not required in this state, it's a good idea to ensure that your car passes its emissions tests.

Smog Check Requirements in Kentucky

Although not required in this state, it's a good idea to ensure that your car passes its emissions tests.

Smog Check Requirements in Louisiana

Vehicles in Louisiana that are model years 1980 or newer, gasoline-powered passenger cars, and gasoline-powered light and heavy-duty trucks weighing 10,000 pounds or less are required to pass an emissions test if they're registered in the following Baton Rouge ozone non-attainment areas:

• Ascension
• East Baton Rouge
• Iberville
• Livingston
• West Baton Rouge

Vehicles within two model-years are exempt from testing requirements, though they will still need to receive a visual anti-tampering check, as well as a gas cap integrity test.

Smog Check Requirements in Maine

Only vehicles in Cumberland county are required to pass an emissions test.

Smog Check Requirements in Maryland

New vehicles (i.e., vehicles registered for the first time) in Maryland are required to pass an emissions inspection at least 36 months from the date of registration. About half of the counties in Maryland require an emissions inspection every two years. If your vehicle is required to pass an emissions inspection, you'll receive a notice by email about 11 weeks before the due date. If you do not have an email address on file, you'll get a notice in the mail 6-8 weeks before the due date.

Smog Check Requirements in Massachusetts

Vehicles in Massachusetts must pass an annual inspection, which often includes an emissions inspection. Vehicles under 15 years old will need to pass an OBD-II scan, and vehicles over 15 years old will need to pass a visual check to make sure the vehicle isn't producing any visible smoke.

Smog Check Requirements in Michigan

Although not required in this state, it's a good idea to ensure that your car passes its emissions tests.

Smog Check Requirements in Minnesota

Although not required in this state, it's a good idea to ensure that your car passes its emissions tests.

Smog Check Requirements in Mississippi

Although not required in this state, it's a good idea to ensure that your car passes its emissions tests.

Smog Check Requirements in Missouri

Missouri requires vehicles to pass an emissions test if the vehicle is gas-powered and model year 1996 or older, diesel-powered and model year 1997 or newer, and vehicles 8,500 pounds or less. Emissions testing is only required in the following areas:

• St. Louis City
• St. Louis County
• St. Charles County
• Franklin County
• Jefferson County

Smog Check Requirements in Montana

Although not required in this state, it's a good idea to ensure that your car passes its emissions tests.

Smog Check Requirements in Nebraska

Although not required in this state, it's a good idea to ensure that your car passes its emissions tests.

Smog Check Requirements in Nevada

Certain vehicles are required to pass an emission inspection for the annual registration renewal. Your renewal notice will let you know if an emission inspection is required for your vehicle. Only vehicles registered in the urban areas of Clark and Washoe county are required to receive an emission inspection.

Smog Check Requirements in New Hampshire

In New Hampshire, vehicles under 20 years old will need to pass an annual on-board diagnostics test as part of the inspection process for vehicle registration renewal.

Smog Check Requirements in New Jersey

Vehicles in New Jersey must pass an emissions test every two years, and new vehicles need a five-year inspection. Motorcycles, farm vehicles, collector and historic vehicles, trailers, mopeds, and cars model year 1995 and older are not required to complete an emissions inspection.

Smog Check Requirements in New Mexico

Every two years, vehicles model year 1983 and newer that are registered in or commuting to Bernalillo County are required to pass an emissions test.

Smog Check Requirements in New York

Each year, vehicles model year 1996 and newer must pass an OBD-II emissions inspection. Older vehicles must pass a visual emissions check. Vehicles that are 16 model years or older do not require an emissions inspection, nor do vehicles 2 model years or newer.

Smog Check Requirements in North Carolina

An annual emission test is required for the following counties: Alamance, Buncombe, Cabarrus, Cumberland, Davidson, Durham, Forsyth, Franklin, Gaston, Guilford, Iredell, Johnston, Lee, Lincoln, Mecklenburg, New Hanover, Onslow, Randolph, Rockingham, Rowan, Union, and Wake. Vehicles within the last 3 model years that have fewer than 70,000 miles are exempt from emissions testing.

Smog Check Requirements in North Dakota

Although not required in this state, it's a good idea to ensure that your car passes its emissions tests.

Smog Check Requirements in Ohio

Ohio’s vehicle emissions testing program is called E-Check, and it identifies vehicles that emit excessive levels of pollutants into the air. Currently, seven counties in Ohio are required to go through emissions testing in order to renew their vehicle's registration:

• Cuyahoga
• Geauga
• Lake
• Lorain
• Medina
• Portage
• Summit

Smog Check Requirements in Oklahoma

Although not required in this state, it's a good idea to ensure that your car passes its emissions tests.

Smog Check Requirements in Oregon

Emissions testing is required for vehicles new to Oregon. Any vehicle model year 1975 and new that is gas powered registered within the Portland metro area will likely need to pass an emissions test.

Smog Check Requirements in Pennsylvania

Most gas-powered vehicles under 9,000 are required to pass an emissions check in the following counties in Pennsylvania: Cambria, Centre, Chester, Cumberland, Dauphin, Delaware, Erie, Lackawanna, Lancaster, Lebanon, Lehigh, Luzerne, Lycoming, Mercer, Montgomery, Northampton, Philadelphia, Washington, Westmoreland and York.

Smog Check Requirements in Rhode Island

With the exception of motorcycles, all vehicles under 8,500 pounds must pass an emissions test every two years.

Smog Check Requirements in South Carolina

Although not required in this state, it's a good idea to ensure that your car passes its emissions tests.

Smog Check Requirements in South Dakota

Although not required in this state, it's a good idea to ensure that your car passes its emissions tests.

Smog Check Requirements in Tennessee

Tennessee requested to eliminate the vehicle emissions tested on February 27, 2020. If EPA approves the plan, the program will end after approval. For now, vehicles in Hamilton, Rutherford, Sumner, Williamson, and Wilson counties are required to pass an annual emissions test.

Smog Check Requirements in Texas

Texas vehicles capable of being powered by gasoline that are from 2 to 24 years old must undergo an annual emissions test if they are registered in any of the following counties:

• Dallas
• Tarrant
• Denton
• Collin
• Ellis
• Johnson
• Kauffman
• Parker
• Rockwell
• Harris
• For Bend
• Brazoria
• Galveston
• Montgomery
• El Paso
• Travis
• Williamson

Smog Check Requirements in Utah

With a few exceptions, vehicles in Salt Lake County with model years under 6 years old must pass an emissions test every two years.

Smog Check Requirements in Vermont

In most cases, vehicles must pass an emissions test at the time of annual inspection.

Smog Check Requirements in Virginia

Vehicles in urban and suburban areas in Northern Virginia must pass an emissions test every two years in order to renew the vehicle's registration.

Smog Check Requirements in Washington

Although not required in this state, it's a good idea to ensure that your car passes its emissions tests.

Smog Check Requirements in West Virginia

Although not required in this state, it's a good idea to ensure that your car passes its emissions tests.

Smog Check Requirements in Wisconsin

Emissions testing is required every two years in Kenosha, Milwaukee, Ozaukee, Racine, Sheboygan, Washington, and Waukesha counties for all vehicles manufactured 1996 or newer.

Smog Check Requirements in Wyoming

Although not required in this state, it's a good idea to ensure that your car passes its emissions tests.

Visit your state's Department of Motor Vehicle's website for more smog check information.

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