TITLE XXI
MOTOR VEHICLES

CHAPTER 266
EQUIPMENT OF VEHICLES

Weight

Section 266:18-d

    266:18-d Additional Certification and Registration. –
I. No vehicle shall be driven on any way with a gross vehicle weight in excess of the weight limits specified in RSA 266:18-a without having obtained a certification therefor from the commissioner of the department of safety. The certification shall be in addition to any other requirements provided by law. Any vehicle so certified may be driven on any way other than the interstate or defense highway system in accordance with the limits established by RSA 266:18-b.
II. The commissioner shall issue said certificate upon receiving proper application. The application shall be accompanied by an additional fee of $105 and the certification shall be in effect for a period of one year. The certification shall expire upon the sale or transfer of the vehicle. The certification shall cover a power unit and not more than one trailer.

[Paragraph III effective until January 31, 2026; see also paragraph III set out below.]


III. Vehicles so certified include the power unit and trailer. The vehicle shall be certified upon submission to the department of documentation satisfactory to the department from the manufacturer attesting that the vehicle is capable of safely carrying the additional weight. Such attestation shall be required upon the first application for certification and a new attestation shall be required at any time when the configuration of the vehicle relative to power unit, axles, springs, or other safety items that could affect the vehicle's ability to qualify for an excess weight certification is altered. Such attestation shall designate the maximum safe gross weight for the vehicles as determined by the components and the summation of the manufacturer's axle design limits for each axle of the vehicle. The power unit and trailer shall be required at all times to have a current inspection sticker or decal from an official inspection station.

[Paragraph III effective January 31, 2026; see also paragraph III set out above.]


III. Vehicles so certified include the power unit and trailer. The vehicle shall be certified upon submission to the department of documentation satisfactory to the department from the manufacturer attesting that the vehicle is capable of safely carrying the additional weight. Such attestation shall be required upon the first application for certification and a new attestation shall be required at any time when the configuration of the vehicle relative to power unit, axles, springs, or other safety items that could affect the vehicle's ability to qualify for an excess weight certification is altered. Such attestation shall designate the maximum safe gross weight for the vehicles as determined by the components and the summation of the manufacturer's axle design limits for each axle of the vehicle.
IV. A vehicle so certified shall be considered to have reciprocity with other states granting New Hampshire similar reciprocity for the full weight limit designated in RSA 266:18-b or the weight limit for which the vehicle is registered, whichever is less.
V. Upon certification a vehicle shall be eligible for an additional registration authorizing the driving of the vehicle in accordance with the weight limits established in RSA 266:18-b. The fee for such additional registration shall be determined in accordance with the vehicle registration fee provided by law and shall be in addition to the certification fee contained in paragraph II.
V-a. Out-of-state carriers operating under apportioned registration and requesting to carry additional weight shall comply with the requirements of this section and shall be registered for the additional weight they are certified to carry in order to be eligible for certification.
V-b. If a vehicle is declared out of service for a safety violation or is issued a citation for an axle distance violation, the certification shall be inoperative until the condition has been rectified.

[Paragraph VI effective until January 31, 2026; see also paragraph VI set out below.]


VI. The commissioner or his designee may revoke or suspend any additional registration granted pursuant to paragraph V of any vehicle or vehicles which are being driven in violation of the limits established by RSA 266:18-b or any other provision of law as evidenced by a record of such violations. The commissioner shall adopt rules pursuant to RSA 541-A pertaining to the procedures for such revocation or suspension and the application, certification, and inspection process for additional truck weights, as well as procedures to become certified as a vehicle inspector for additional weights.

[Paragraph VI effective January 31, 2026; see also paragraph VI set out above.]


VI. The commissioner or his designee may revoke or suspend any additional registration granted pursuant to paragraph V of any vehicle or vehicles which are being driven in violation of the limits established by RSA 266:18-b or any other provision of law as evidenced by a record of such violations. The commissioner shall adopt rules pursuant to RSA 541-A pertaining to the procedures for such revocation or suspension and the application and certification process for additional truck weights, as well as procedures to become certified as a vehicle inspector for additional weights.

Source. 1986, 121:3. 2004, 56:1. 2009, 28:1, 2. 2012, 171:13, eff. Aug. 10, 2012. 2025, 141:245, 246, eff. Jan. 31, 2026.