Department of Transportation
NHDOT
New Hampshire • United States of America
The New Hampshire Department of Transportation (NHDOT) manages approximately 4,200 miles of state highways in a compact but strategically located state within the Northeast freight network. Key corridors include I-93, I-89, I-95 (a short segment), and US-3. While geographically small, New Hampshire serves as a vital link in the northern New England freight network connecting Massachusetts to Maine and Quebec. NHDOT administers commercial vehicle regulations, manages weigh stations, and operates the NH511 travel information system. The department also manages the F.E. Everett Turnpike, an important freight route for commercial vehicles navigating the state's southern corridor.
| Official Website | https://www.nh.gov/dot/ |
|---|---|
| Data API | https://www.dot.nh.gov/ |
| Founded | 1905 |
| Headquarters | Manchester |
Available Data
New Hampshire Trucking Regulations
Size & weight limits, OS/OW permits, and seasonal restrictions for commercial vehicles
Weight Limits
| Category | Limit |
|---|---|
| Max Gross Vehicle Weight | 80000 lbs |
| Single Axle | 22400 lbs |
| Tandem Axle | 36000 lbs |
Dimensional Limits
| Category | Limit |
|---|---|
| Max Height | 13.5 ft |
| Max Width | 8.5 ft |
| Max Length (Single Unit) | 40 ft |
| Max Length (Combination) | 65 ft |
OS/OW Permits
Seasonal Restrictions Mar, Apr, May
New Hampshire has significant spring weight restrictions on state and town roads, typically March through May. The White Mountains region has longer restriction periods due to elevation and terrain. Town roads often remain posted after state highways are lifted.
Weigh Station Bypass
24¢/gal
Member
Special Exemptions
Notable Rules
New Hampshire allows higher axle weights on paved state roads (22,400 lbs single, 36,000 lbs tandem). I-93 and I-89 are the primary freight corridors. The White Mountains (including Franconia Notch on I-93) present challenging terrain. Many covered bridges and rural roads have strict weight restrictions. Spring weight restrictions on town roads can last into late May in northern NH.