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What States Require Emissions Testing?

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Emissions testing has become much more widespread in the past few years. The majority of states in the US require at least some form of emissions testing, although the frequency and areas vary greatly. Most states that do require testing only require it in certain areas, but there are a handful that require testing in all areas.

What states require testing?

Currently, there are 33 states that require testing in all or some areas. These include the following:

  • Arizona: Certain Areas (Phoenix and Tucson)
  • California: All Areas
  • Colorado: Some Areas (Denver and Boulder)
  • Connecticut: All Areas
  • Delaware: All Areas
  • Georgia: Certain Areas (all 13 Atlanta Metro Counties)
  • Idaho: Certain Areas (City of Boise and Ada County)
  • Illinois: Certain Areas (Chicago and East St. Louis)
  • Indiana: Certain Areas (Gary Metro Area)
  • Maine: Certain Areas (Cumberland County, and the Portland Metro Area)
  • Maryland: Certain Areas (all DC Metro and the City of Baltimore)
  • Massachusetts: All Areas
  • Missouri: Certain Areas (Jefferson County and Franklin County)
  • Nevada: Certain Areas (Cities of Reno and Las Vegas)
  • New Hampshire: All Areas
  • New Jersey: All Areas
  • New Mexico: Certain Areas (Albuquerque Metro Area)
  • New York: All Areas
  • North Carolina: Certain Areas (48 Counties – See the NC DMV site for more info).
  • Ohio: Certain Areas (Cities of Akron and Cleveland)
  • Oregon: Certain Areas (Cities of Medford and Portland)
  • Pennsylvania: Certain Areas (Cities of Pittsburgh and Philadelphia)
  • Tennessee: Certain Areas (Cities of Nashville and Memphis)
  • Texas: Certain Areas (Cities of Austin, Houston, Dallas/Fort Worth and El Paso)
  • Utah: Certain Areas (Cities of Ogden, Provo and Salt Lake)
  • Vermont: All Areas (1996 or Newer Vehicles Only)
  • Virginia: certain Areas (all DC Metro and Arlington)
  • Washington: Certain Areas (Cities of Seattle, Spokane, Tacoma and Vancouver)
  • Washington DC: All Areas
  • Wisconsin: Certain Areas (all of SE Wisconsin and the City of Milwaukee)

The list above is subject to change at any time. Emissions regulations shift frequently. The best source of information regarding your specific testing requirements will be from your state’s DMV or DOT website (some states make this information available from the Department of Consumer Affairs, as well). You can also check the handy guide at, which provides information about all 50 states.

What makes an area likely to require testing?

Those states that mandate emissions testing in only certain areas generally follow a simple rule – if the area is heavily trafficked and urbanized, there’s a chance that you’ll need to have your car tested annually. For instance, Georgia requires testing in Atlanta and the Atlanta metro area (the counties immediately surrounding Atlanta/Fulton County).

The statements expressed above are only for informational purposes and should be independently verified. Please see our terms of service for more details

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