Do You Need an Emissions Test to Buy a Used Car in Utah?

Maybe. Whether you need an emissions test to buy a used car in Utah depends on the county where you'll register it and the car's model year. Several Wasatch Front counties require a passing emissions certificate before you can register a vehicle, and newer cars are often exempt or tested less often. The rules change, so confirm the details for your county and your car before you commit.

Which Utah counties require an emissions test?

Emissions testing is tied to the county where the vehicle is registered, not where you bought it. Davis, Salt Lake, Utah, and Weber counties have emissions programs. If you live in one of those counties, expect to need a current certificate when you register a used car. Other counties may have different rules or none at all. Your county health department is the authority on its own program.

Does the age of the car change the answer?

Yes. In general, brand-new vehicles are exempt for the first couple of model years, newer vehicles are tested every other year, and older vehicles are tested every year. Diesel vehicles and very old vehicles follow their own rules. Because the exact cutoffs have been adjusted over time, check the current model-year rules with the Utah DMV or your county health department rather than relying on a number from an old article.

Who is responsible for the test when you buy a used car?

That depends on the seller and the paperwork, so ask early. Before you sign, ask whether the car has a current emissions certificate, when it was issued, and whether the car passed. A certificate is only good for a limited window, so a test done months ago may not carry over to your registration. Put the answer in writing, and read it against the purchase agreement. Our guide on how to read a used car purchase agreement shows where to look.

What if you're buying a car from out of state?

Cars brought in from another state usually need extra steps to register in Utah, such as a VIN inspection, and may also need an emissions inspection depending on your county and the car's age. Ask the DMV what applies before you pay, so you don't end up with a car you can't register right away.

What happens if the car fails?

A failed test usually means repairs and a retest before you can register. That cost can be large, which is one more reason to get a pre-purchase inspection and to ask for a passing certificate as part of the deal. A check engine light is a common reason for a failure, so treat one as a question for the seller, not a detail to ignore.

How do you handle this when buying online?

The same rules apply. When you buy online, the car is registered in your county, so the county's emissions requirements still apply to you. Ask the dealer how emissions paperwork is handled before you sign. You can browse what's available on our used car inventory, and our page on buying a car online in Utah walks through the full process from start to delivery.

Frequently asked questions

Do I need an emissions test to register a used car in Utah? It depends on your county and the car's model year. Davis, Salt Lake, Utah, and Weber counties have emissions programs; check the current rules for your car.

Do new cars need an emissions test? Very new vehicles are generally exempt for their first few model years. Confirm the current cutoff with the DMV.

Can I buy a car that hasn't passed emissions? You can, but you may not be able to register it until it passes. Ask for a current certificate before you buy.

Where do I confirm the rules? Your county health department and the Utah DMV publish the current requirements.