The following information about New Hampshire Oversize Permits is for informational purposes only. It’s important to always read your permits and provisions sheets carefully as we cannot guarantee the accuracy of the information provided. If you have any questions or need assistance, you can contact the following number.

New Hampshire DOT #: 603-271-2691

New Hampshire Oversize Permits Duration

Oversize permits in New Hampshire are effective for a duration of five travel days, and it is imperative to obtain the permit before entering the state.

Operating Time

Monday through Friday, over dimensional loads are permitted to travel from half an hour before sunrise to half an hour after sunset. Weekend and holiday travel is not allowed for over dimensional loads. However, there are no travel time restrictions for overweight loads.

Restricted Travel

Journeys through the city of Manchester are limited between 7:00 a.m. and 9:00 a.m., as well as from 3:00 p.m. to 6:00 p.m. The toll road regulations align with those of other highways. Additionally, travel is prohibited on major holidays, with certain restrictions applicable during holiday weekends.

Call (832) 454-5883 For Permit Consultation

Legal Dimensions

Length:

  • 53′ semi-trailer on Interstate and designated highways (41′ Kingpin to center of rear tandem)
  • 48′ on all other roads

There are no length restrictions for vehicles transporting poles, pipes, logs, timbers, or steel beams (excluding stretch trailers).

Width:

8′-6″

Height:

13′-6″

Weight:

80,000 Gross

  • Single – 20,000 designated highways* (22,400 other roads)
  • Tandem – 34,000 designated highways* (36,000 other roads)
  • Tridem – Same as tandem
  • When the Gross Vehicle Weight (GVW) is not exceeding 73,280 pounds, the legal weight limit is 22,440 pounds on a single axle and 36,000 pounds on a tandem.

Routine Permit Limits

Length:

110′

Width:

16′

Height:

16′

Weight:

  • Single – 25,000
  • Tandem – 50,000
  • Tridem – 70,000
  • Quad – 85,000

Loads exceeding these dimensions are treated as super loads.

Bridge Review for New Hampshire Oversize Permits

A bridge review is mandated under the following conditions: when any single axle surpasses 27,500 pounds, any axle of a tandem exceeds 25,000 pounds, any axle of a tridem exceeds 22,500 pounds, any axle of a quad exceeds 20,000 pounds, any 5-axle combination exceeds 100,000 pounds, any 6-axle combination exceeds 120,000 pounds, any 7-axle combination exceeds 130,000 pounds, and any combination of 8 or more axles exceeds 149,999 pounds.

New Hampshire Oversize Permits image

Escort Conditions for New Hampshire Oversize Permits

Length:

  • At 80′ – one escort
  • Over 100′ – State Police escort (need 48 hour notice) unless they exempt it

Overhang:

  • Over 15′ – one escort
  • On a two-lane undivided highway, two escorts are required if overhang exceeds 15′ and width is over 12′

Width:

  • At 12′ – one escort
  • Over 15′-1″ – one state police escort
  • Over 18′ – two State Police escort (need 48 hour notice). State may require a second escort for some routes

Height:

A route survey may be necessary for heights exceeding 13 feet and 6 inches, although an escort is typically not required for height.

Signs, Flags & Lights

An “Oversize Load” sign is necessary on the front of the oversize vehicle and on the rear, whichever provides the best rear display. Red flags, at least 12 inches square, must be mounted on all extremities of the load when it extends over the sides of the trailer by more than 4 inches. If the rear overhang surpasses 4 feet, one flag should be displayed at the end of the overhang if it’s less than 2 feet wide and two flags if the overhang is over 2 feet wide. No specific lighting requirements apply.

Seasonal Load Restrictions

In the spring thaw period, weight limits may be restricted to 20,000 gross axle weight or less.