In the US, most states require some form of vehicle inspection. Many of them require periodic evaluation, while some, like Maryland, only require it at registration of the vehicle and transfer of ownership. Most states employ government -operated inspection centers, but others, like New York and North Carolina, use private garages that require DMV approval.

Although there are many differences in auto inspection laws and regulation, they all have the same purpose; ensuring that the vehicles are safe for people and for the environment. For safety purposes, inspectors check vehicle components like the brakes and taillights. And for the environment, inspectors ensure that the chemical content of emissions is within acceptable ranges.

Fees for inspection vary wildly from state to state and even within state. For instance, in North Carolina, there is a $6.25 state fee for emissions inspection and a labor fee that can be $0.00 or as high as $23.75. It's similar for safety inspection, and states with window tint laws usually charge an extra fee to check the tint level during the inspection. In NC, total cost can be anywhere from $33.45 to $67.20.

When a vehicle fails inspection for any reason, the vehicle is no longer legal and it remains that way until the vehicle owner remedies the situation and has the vehicle inspected again. However, most states with periodic auto inspection allow citizens a grace period for failure. In many cases, the state provides a temporary sticker and gives the owner 30 days to repair the vehicle, re-inspect it and register it. The cost of inspection usually includes one re-inspection.

Another common form of auto inspection occurs prior to the purchase of a used car, especially when dealing with a private seller. This kind of auto inspection serves several purposes. It ensures the buyer that the vehicle would pass the state inspection and that the vehicle is in the expected condition. These auto inspections tend to be extensive and include the cooling system and other aspects of the car not normally required by state-mandated inspection. Because of this, these are also popular as preventative maintenance, and many shops do it as part of a tune-up and similar services.