Drivers in the state of Tennessee
who reside in a county with mandatory testing must get their vehicles to pass a vehicle emissions test (a.k.a. a “smog check”) before being able to obtain a Tennessee vehicle registration
or registration renewal. Counties with mandatory smog checks include:
Gas and diesel vehicles weighing less than 10,500 lbs and made in 1975 or newer, must get a Tennessee smog check. This includes salvaged, homemade, rebuilt, and hybrid vehicles.
Brand new vehicles getting their first registration, motorcycles, vehicles weighing more than 10,500 lbs, all-electric vehicles, and vehicles with antique registrations are exempt.
Smog checks must be performed annually and cost $9.
MORE: How to pass emissions testing