Does New Hampshire Have Emissions Testing?
New Hampshire is eliminating its mandatory vehicle emissions testing program for most passenger vehicles effective January 31, 2026.
Policy effective February 1, 2026:
- No emissions testing will be required for passenger vehicles
- No counties will require emissions testing
- No cities or municipalities will have local emissions requirements
- All vehicle types will be exempt from emissions testing requirements
- No testing will be required for initial registration or annual renewal
Previous Emissions Testing Programs
Emissions Testing Program (1999-2026): New Hampshire implemented mandatory vehicle emissions testing on January 1, 1999, following a U.S. Environmental Protection Agency determination that portions of southern New Hampshire contributed to ozone pollution in the region. The program required on-board diagnostics (OBD II) testing for vehicles less than 20 years old as part of the state's annual inspection requirement.
As part of the 2026-2027 state budget (House Bill 2), signed into law by Governor Kelly Ayotte on June 30, 2025, New Hampshire repealed mandatory annual safety inspections and emissions/on-board diagnostics testing for most passenger vehicles effective January 31, 2026.
The decision to discontinue the program was based on several factors:
- Legislative determination that the program was no longer necessary to meet air quality objectives
- Elimination of the administrative burden and cost to vehicle owners associated with annual inspections
- New Hampshire's withdrawal from the Ozone Transport Commission, a regional agreement aimed at limiting ozone pollution
- Changes in vehicle technology and federal emission standards have reduced the need for state-level testing programs
