Texas emissions testing is required in 10 counties, not statewide

Only 10 Texas counties require emissions testing. They are Bexar, Collin, Dallas, Denton, El Paso, Fort Bend, Galveston, Harris, Jefferson, and Tarrant. If you live outside these counties, you do not need to test your vehicle for emissions, even if you register it in Texas.

The Texas Commission on Environmental Quality (TCEQ) designates which counties must test based on air quality data. Counties that do not meet federal air quality standards must require testing. Most of Texas, including rural areas and smaller cities, has no testing requirement.

If you move to one of these 10 counties or buy a vehicle there, you will need to test before you register or renew registration. The test itself costs between $25 and $50 depending on your vehicle type and the testing station.

Key Takeaways

  • Only Bexar, Collin, Dallas, Denton, El Paso, Fort Bend, Galveston, Harris, Jefferson, and Tarrant counties in Texas require emissions testing.
  • You need a passing emissions test before you can register a vehicle or renew registration in one of these 10 counties.
  • The test checks whether your vehicle's exhaust meets state pollution standards and typically takes 10 to 15 minutes.
  • You can find testing stations through the TCEQ website or by searching "emissions testing near me" in your county.

The 10 counties that require testing, by region

North Texas has four counties: Collin, Dallas, Denton, and Tarrant. These surround the Dallas-Fort Worth area. If you live in or around Dallas, Fort Worth, Arlington, Plano, or Frisco, you need testing.

Houston area has three counties: Harris, Fort Bend, and Galveston. Harris County includes Houston itself. Fort Bend is southwest of Houston. Galveston is on the coast.

South Texas has Bexar County, which includes San Antonio and its suburbs.

West Texas has El Paso County, which includes El Paso and surrounding areas.

Southeast Texas has Jefferson County, which includes Beaumont and Port Arthur.

When you need to test your vehicle

You must pass an emissions test before you register a new vehicle in one of the 10 counties. You also must test before you renew your registration every two years. Some counties require testing every year instead of every two years — check with your county tax assessor-collector's office to confirm the schedule for your county.

If you move to one of these counties from outside Texas or from a county that does not require testing, you have 30 days to get your vehicle tested and registered. You cannot legally drive without a valid registration, so plan to test within the first two weeks of moving.

If your vehicle fails the test, you have 15 days to repair it and retest at no additional cost at the same station. If it fails again, you can take it to a different station for a second opinion, but you will pay the testing fee again.

How to find a testing station in your county

The TCEQ maintains a searchable list of licensed testing stations on its website. You can search by county or by zip code. Most stations are open Monday through Friday during business hours, and some are open on Saturday mornings.

You can also search online for "emissions testing" or "smog check" plus your city name. Independent repair shops, tire shops, and dedicated testing stations all perform emissions tests. Call ahead to confirm hours and whether you need an appointment — many stations accept walk-ins, but some require you to book a time slot.

Bring your vehicle registration and a photo ID. The test takes 10 to 15 minutes. You will receive a printed receipt or a digital pass that you can show to the tax assessor-collector's office when you register or renew.

What happens if you fail the test

A vehicle fails emissions testing when its exhaust contains too much nitrogen oxide, particulate matter, or other pollutants. Common reasons for failure are a faulty oxygen sensor, a malfunctioning catalytic converter, or a check engine light that is on.

You do not have to repair the vehicle at the testing station. You can take it to any mechanic or repair shop. Many independent shops charge $100 to $300 to diagnose and fix the problem, depending on what is wrong. Once you repair it, you can return to any licensed testing station to retest.

If you cannot afford repairs, some counties offer repair information programs. Contact your county's health department or environmental office to ask whether a program exists in your area.

If you live outside the 10 counties

If you live in a Texas county that does not require emissions testing, you do not need to test your vehicle before registration or renewal. You can register and renew online through your county tax assessor-collector's website, by mail, or in person at the office.

However, if you move to one of the 10 counties later, you will need to test before you can register your vehicle there. Plan ahead if you know you are relocating to Dallas, Houston, San Antonio, El Paso, or another city in a testing county.

Frequently Asked Questions

Do I need emissions testing if I just moved to Texas from another state?

Only if you move to one of the 10 testing counties. If you move to a county that does not require testing, you do not need to test. You will need to register your vehicle in Texas within 30 days of moving, but registration does not require a test unless you are in Bexar, Collin, Dallas, Denton, El Paso, Fort Bend, Galveston, Harris, Jefferson, or Tarrant County.

What if my vehicle is older than 25 years?

Most counties exempt vehicles older than 25 years from emissions testing. Check with your county tax assessor-collector's office to confirm the exemption applies to your vehicle, as some counties have different rules for classic or antique vehicles.

Can I test my vehicle before I register it?

Yes. You can test your vehicle at any licensed station in your county before you go to the tax assessor-collector's office. The test result is valid for 30 days, so test within a month of when you plan to register.

What if I buy a used car from a private seller in a testing county?

You must test the vehicle before you register it in your name. The seller does not have to provide a test result. You are responsible for testing before registration, so plan to test within the first two weeks of purchase.

Does a vehicle inspection include emissions testing?

No. Texas vehicle safety inspections and emissions tests are separate. You need both in the 10 testing counties. The safety inspection checks brakes, lights, and steering. The emissions test checks exhaust pollution. You can do them at the same station, but you pay for each separately.