Emissions Testing in New Hampshire

Testing Requirements

Current Testing Requirements in New Hampshire

New Hampshire's vehicle inspection program is suspended as of February 2026. Before the suspension, the state required an annual combined safety and emissions inspection for most registered vehicles statewide. The program was called the New Hampshire OBD and Safety Testing (NHOST) program and was operated by Gordon-Darby under contract with the state. The safety inspection covered brakes, tires, lights, steering, suspension, windshield, wipers, mirrors, horn, seat belts, and exhaust system. The emissions portion was an OBD-II scan for vehicles with onboard diagnostic systems. The state legislature included a repeal of the inspection mandate in the 2025 budget law (HB 2), effective January 31, 2026. A federal court injunction temporarily blocked the repeal, but the state has no vendor to operate the program, resulting in a suspension. New Hampshire is also petitioning the EPA to remove the state from the Ozone Transport Region, which would eliminate the federal requirement for vehicle emissions testing.

Who Needs a Vehicle Inspection

While the program was active, all registered motor vehicles in New Hampshire were required to pass an annual combined safety and emissions inspection. The OBD-II emissions scan applied to passenger vehicles less than 20 years old. Commercial vehicles remain subject to federal annual inspection requirements regardless of the state program's status. During the current suspension, passenger vehicles are not required to obtain inspections because no vendor is operating the program. Drivers remain legally responsible for maintaining safe vehicles under RSA Chapter 266.

How Often Tests Are Required

When the program was active, inspections were required annually, due during the owner's birth month. During the current suspension, no inspection schedule is being enforced for passenger vehicles. If the program is reinstated, annual inspections would resume. Commercial vehicles continue to follow federal inspection schedules.

Where Emissions Testing Is Required

When the program was active, emissions testing was required statewide. New Hampshire was one of the few states that required both safety and emissions inspections annually for all vehicles statewide. During the current suspension, no areas require testing because the program has no operating vendor.

What Happens During the Test

When the program was active, the inspection began with a safety check covering brakes, tires, lights, steering, suspension, windshield, wipers, mirrors, horn, seat belts, and exhaust system. The emissions portion for vehicles with OBD-II systems included a diagnostic scan checking for stored trouble codes, readiness monitor status, and the check engine light. A lit check engine light caused failure. New Hampshire did not perform a tailpipe emissions test. The inspection typically took 15 to 30 minutes at a licensed inspection station. The combined inspection cost approximately $50 at most stations.

Areas in New Hampshire That Require Emissions Testing

When the program was active, emissions testing was required statewide. Cities such as Manchester, Nashua, Concord, Derry, Dover, Rochester, Salem, Merrimack, Hudson, Londonderry, Keene, Bedford, Portsmouth, Laconia, Lebanon, Claremont, Somersworth, Hanover, Exeter, and Hampton were all included. During the current suspension, no areas require testing.

How the Vehicle Inspection Works in New Hampshire

During the suspension, the inspection program is not operational. Inspection stations cannot issue state inspection stickers. When the program was active, drivers took their vehicle to any licensed inspection station, which included auto repair shops, dealerships, and service stations throughout the state. No appointment was typically required. The inspection fee was approximately $50 at most stations, covering both safety and emissions components. If the vehicle passed, it received an inspection sticker valid for one year. If it failed, the owner had to complete repairs and return for reinspection. The status of the program is subject to change based on court proceedings, legislative action, and the EPA's decision on New Hampshire's petition for removal from the Ozone Transport Region. Drivers should check dmv.nh.gov for current guidance.