The specific year your car needs an emissions test depends almost entirely on the state you live in, not a single federal model year. There is no universal rule. However, a common requirement in many states that have testing programs is for gasoline-powered vehicles that are model year 1996 or newer. This is because 1996 was the year federally mandated On-Board Diagnostics II (OBD-II) systems became standard, making testing more streamlined.
States set their own rules under the framework of the federal Clean Air Act. For example, California's SMOG check program requires biennial testing for most vehicles older than eight model years. Other states, like many in the Northeast, have similar programs but may exempt newer vehicles for the first few years. Some states have no emissions testing requirements at all.
The most critical factor is your vehicle's age. Newer cars (often those under 4-5 years old) are frequently exempt. Very old cars (e.g., pre-1976) are often exempt as "classic" vehicles. The best course of action is to check your state's Department of Motor Vehicles (DMV) or environmental agency website for the exact criteria.
| State Examples | Testing Program Name | Typical Model Year Requirement | Exemption for New Vehicles | Testing Frequency |
|---|
| California | SMOG Check | 1976 and newer (with exceptions) | First 8 model years | Biennial (every 2 years) upon registration transfer |
| New York | Emission Inspection | Most vehicles 2 model years and older | First 2 model years | Annual |
| Texas (Certain Counties) | Vehicle Emissions Inspection | 2 through 24 model years old | First 2 model years | Annual with safety inspection |
| Colorado (Certain Areas) | Air Care Colorado | 7 model years and older | First 7 model years | Biennial |
| Pennsylvania | Emissions and Safety Inspection | Most gasoline vehicles 1975 and newer | None for model year, based on weight | Annual |
