North Dakota OS/OD Overview
Permit Required
Yes – any oversize or overweight load requires a permit from the North Dakota Department of Transportation (NDDOT).
Legal Limits (Without Permit)
- Width: 8'6"
- Height: 14'
- Length: 75' (combo); 53' trailer allowed
- Weight: 105,500 lbs GVW (on approved roads with proper axle spacing)
Permitted Load Maximums (Typical Upper Limits)
- Width: Up to 18' with proper escorts
- Height: Over 15'6" requires route survey and utility coordination
- Length: Over 120' with special review
- Weight: 250,000+ lbs with engineering analysis
Superloads require additional time, routing, and may involve bridge clearance approvals and law enforcement escorts.
Travel Hours
- Standard: Sunrise to Sunset
- Weekend: Loads under 16' wide and 110' long may travel on weekends
- Holidays: No movement on major holidays or after noon the day before
- Night travel: Permitted for loads under 12' wide with lighting and specific approval
Escort Requirements (General Guidelines)
| Dimension | Escort Requirement |
|---|---|
| Width > 14' | 1 Escort (rear on 4-lane, front on 2-lane) |
| Width > 16' | 2 Escorts (front and rear) |
| Height > 15'6" | High pole escort required + route clearance |
| Length > 120' | 1 or more Escorts depending on route and configuration |
Additional Notes
- “Oversize Load” signs, flags, and amber beacon lights are required on loads and escorts
- Seasonal road restrictions (frost laws) apply during spring thaw – check before moving
- Permits are issued through the NDDOT Online Permitting System (ePermits)
Detailed Information
PERMITS: three days. Must have permit prior to entering the state.
OPERATING TIME: One-half hour before sunrise to one-half hour after sunset, including Saturday and Sunday except loads over 16 feet wide and 110 feet long cannot travel Saturday after noon or Sunday all day. Overweight only can have continuous travel with proper lighting.
RESTRICTED TRAVEL: Travel may be restricted on major holidays or holiday weekends depending on dimensions. (Double check with permit office for holiday restrictions).
LEGAL DIMENSIONS: Width: 8'6" Height: 14'' Length: 53' semi-trailer and load, 75 overall including load and any rear overhang Poles, pipes, beams, utility poles, etc. are not exempt from permits for length or rear overhang. Weight: 80,000 Gross Single – 20,000 Tandem – 34,000 Tridem – 48,000. Register tractor at the maximum of 105,500 pounds to be permitted for that much or more, or pay extra on the O/W permit. Divisible Loads Exceeding 80,000: You can exceed 80,000 gross without a permit on state highways as long as you are legal on all axle/group weights and you are licensed for at least the amount of your gross weight. However, if you need any Interstate route, you will need to get an "Interstate Permit."
ROUTINE PERMIT LIMITS: Width: 18' Height: 17' Length: 200' Weight: Steer – 12,100 for 11" tires (550 pounds per inch of tire width) Single – 24,000 Tandem – 45,000 Tridem – 60,000 Quad – 68,000 Note: ND does not like to issue overweight permits when axle group weights are not evened out as much as possible. Loads exceeding 18’ wide 18 high and 250,000 lbs are considered superloads.
ESCORTS: Width: On 2-lane highways: Over 14'6" up to 16' – 1 escort, Instead of pilot car, for width over 14'6 but not over 16', may be equipped with lighted rotating or flashing amber light(s) that are visible from the front and rear at 500 feet; over 16' – 2 escorts. On 4-lane highways: Over 16' – 1 escort. All highways: Width: Over 18' - Official escort (unless exempted by Highway Patrol). Length: Over 120' – 1 escort Height: Over 18' – 1 escort and written clearances from utility companies.
SEASONAL LOAD (WEIGHT) RESTRICTIONS: Spring thaw load weight restrictions on non-Interstate highways go into effect some time in February and last into May and even much later on a few highways. Weight restrictions range from legal weight only to 8-tons, 7-tons and 6-tons per axle. Ton-mile exceptions are sometimes available, but they are very expensive.
SIGNS, FLAGS & LIGHTS: "Oversize Load" sign is required on rear of the vehicle when overall length exceeds 75'. All overdimensional loads must have flags on the traffic side of the load front and rear. Overwidth and overheight loads only require flags, not signs.