The basics...

 

New Residents

If you are bringing a vehicle into the Denver-Boulder and North Front Range emissions program area from another state or another part of Colorado, including a basic emissions program area, you are required to obtain an emissions inspection and register your vehicle in your new county within 90 days of establishing residency. In addition, you may need a Vehicle Identification Number (VIN) verification.

THERE IS ONE EXCEPTION: When a newer vehicle is brought into the program area and is less than seven (7) years old (from Manufacturer Statement of Origin) the vehicle does not require an emissions inspection at the time of registration. The vehicle will require an emissions inspection when it reaches its eighth (8) model year.