In Texas, you must submit your vehicle to a safety inspection and emissions testing within 30 days of moving to the state. Established residents will need to renew your inspection upon registration renewal.
Safety inspections are mandatory for all vehicles, while emissions tests are required in certain counties only. Brand new vehicles are also exempt from smog checks.
Your car must pass a safety inspection before you can register it; there are no exceptions.
Texas requires all gasoline-powered vehicles 2 to 24 model years old to undergo annual emissions testing (new vehicles don't require emissions testing until they are at least 2 model years old.)