New Hampshire OSOW permits

Permits valid for five travel days. Must have a permit prior to entering the state.

New Hampshire permitting system:

Contact phone number: 1-603-271-2691


One-half hour before sunrise to one-half hour after sunset, Monday through Friday. No weekend or holiday travel for over-dimensional loads. Overweight only are not restricted for travel time.


Travel through the city of Manchester is restricted during the hours of 7:00 a.m. – 9:00 a.m. and 3:00 p.m. – 6:00 p.m. Toll road requirements are the same as other highways. No travel on major holidays, including some holiday weekend restrictions. Check with the Sammons Permit Office.


Width: 8'6"

Height: 13'6"

Length: 53' semi-trailer on Interstate and designated highways (41' Kingpin to the center of rear tandem). 48' on all other roads. Length limitations do not apply to vehicles transporting poles, pipes, logs, timbers, steel beams (not for stretch trailers)

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 GVW isn't over 73,280 pounds, 22,440 pounds legal on a single axle, and 36,000 on a tandem.


Width: 16'

Height: 16'

Length: 90'

Weight: Single – 25,000 Tandem – 50,000 Tridem – 70,000 Loads exceeding these dimensions are treated as super loads.

A bridge review is required when: any single axle exceeds 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, any combination of 8 or more axles exceeds 149,999 pounds.


Width: At 12' – 1 escort; over 18' – 2 State Police escort (need 48 hours notice). The state may require a second escort for some routes.

Height: Route survey may be required for over 13'6 high, escort not usually required for height.

Overhang: Over 15' – 1 escort. On a 2-lane undivided highway, 2 escorts are required if overhang exceeds 15' and the width is over 12'.

Length: At 80' – 1 escort; over 100' – State Police escort (need 48 hours notice) unless they exempt it.


"Oversize Load" sign required on the front of an oversize vehicle and on the rear of the vehicle or load, whichever provides the best rear display. Mount red flags (at least 12" square) on all extremities of the load when load extends over the sides of the trailer more than 4 inches. When rear overhang exceeds 4', 1 flag shall be displayed at the end of the overhang if less than 2' wide, and 2 flags if the overhang is over 2' wide. There are no special lighting requirements.


During the spring thaw, weights may be limited to 20,000 gross axle weight or less. Check with the Sammons Permit Office.

  • Facebook - White Circle
  • Instagram - White Circle