North Dakota Oversize and Overweight Permitting Guide

Operating oversize and overweight (OS/OW) loads in North Dakota requires strict adherence to the North Dakota Department of Transportation (NDDOT) Motor Carrier Division regulations. The state utilizes the North Dakota Travel Information Map and the NDDOT Permit System to manage load movements across its 8,500 miles of state highway. Carriers must secure permits whenever a vehicle exceeds standard legal limits, which include a total width of 8 feet 6 inches, a height of 14 feet, and a gross vehicle weight of 80,000 pounds on the Interstate system or up to 105,500 pounds on designated state routes. Navigating these requirements ensures compliance with North Dakota Century Code Chapter 39-12, preventing costly fines and infrastructure damage. DispatchTool assists carriers in managing these complex regulatory environments by integrating state-specific permit data into truck-safe routing. The platform allows dispatchers to input exact vehicle dimensions and weights to identify routes that avoid restricted bridges or low-clearance structures common in the western Bakken oil fields. By maintaining permit documents and axle weight calculations within the centralized system, fleets can reduce administrative delays and ensure drivers follow permitted paths. Create a DispatchTool account to streamline your North Dakota OS/OW documentation and route planning.

Legal Dimensions and Weight Limits

North Dakota defines legal dimensions under NDCC 39-12-04. Standard legal width is 8 feet 6 inches, while legal height is capped at 14 feet. The maximum length for a single unit is 50 feet, and a tractor-semitrailer combination is generally limited to 75 feet on non-designated highways, though there is no overall length limit on the National Network for standard combinations provided the trailer does not exceed 53 feet. For weight, the state follows the Federal Bridge Formula B. The maximum gross vehicle weight (GVW) without a permit is 80,000 pounds on Interstates 94 and 29. On state highways, the GVW can reach 105,500 pounds depending on axle configurations and spacing, provided no single axle exceeds 20,000 pounds and no tandem axle exceeds 34,000 pounds.

Permit Types and Associated Fees

The NDDOT offers several permit types to accommodate different hauling needs. A Single Trip Permit is valid for one movement within a 72-hour window and typically costs $20 for overweight loads up to 150,000 pounds, plus a ton-mile fee if exceeding that weight. Annual permits are available for specific dimensions: an Oversize Annual Permit costs $100 and covers widths up to 14 feet 6 inches. For heavier loads, the state issues Overweight Seasonal Permits, which are critical during the spring thaw when load restrictions are strictly enforced. Special mobile equipment and work-over rigs used in the oil industry often require specific non-reducible load permits which are priced based on the total GVW and the number of axles utilized.

Escort Vehicle Requirements

Pilot car or escort requirements are triggered based on the specific dimensions of the load. In North Dakota, a single rear escort is generally required for loads exceeding 14 feet 6 inches in width but not exceeding 16 feet on two-lane highways. If a load exceeds 16 feet in width, both a front and a rear escort are mandatory. For height, any load exceeding 18 feet requires a front escort equipped with a high-clearance pole. Length-based escorts are required when a combination exceeds 120 feet. All escort vehicles must be equipped with a two-way radio and a flashing amber light visible for at least 500 feet to warn oncoming traffic of the oversized hazard.

Seasonal Weight Restrictions

The North Dakota DOT implements 'Spring Load Restrictions' to protect the state's highway infrastructure during the spring thaw cycle, usually occurring between February and May. During this period, weight limits on secondary state highways can be reduced to 7 tons or even 6 tons per axle. These restrictions are categorized into levels such as Legal Weight, 7-Ton, 6-Ton, and 5-Ton segments. Carriers must monitor the NDDOT Load Restrictions Map daily, as limits change based on localized soil temperature and moisture data. Violating these seasonal limits results in significant fines calculated per pound of excess weight, which can scale into thousands of dollars for a single violation.

Permit Application Process

All permits must be obtained through the NDDOT online permit system prior to entering the state or moving the load. The system requires a registered account, USDOT number, and active insurance on file. Application data must include the power unit's VIN, license plate number, and the specific axle spacings measured to the nearest inch. For loads exceeding 150,000 pounds or 18 feet in width, the NDDOT requires a minimum of two business days for engineering review and bridge analysis. Self-issue permits are available for standard oversize loads (up to 15 feet wide and 15 feet high) for carriers with established credit accounts, facilitating faster dispatching for routine OS/OW operations.

Travel Time and Holiday Restrictions

Movement for oversized loads is generally restricted to daylight hours, defined as one-half hour before sunrise to one-half hour after sunset. However, loads that are only overweight but within legal dimensions may travel 24/7. North Dakota prohibits the movement of oversized loads on major holidays, including New Year’s Day, Memorial Day, Independence Day, Labor Day, Thanksgiving Day, and Christmas Day. If a holiday falls on a Sunday, the following Monday is typically restricted. Additionally, the NDDOT may restrict travel during inclement weather when visibility is less than 500 feet or when winds exceed 25 miles per hour for high-profile loads.

Bridge and Structure Clearances

North Dakota has several low-clearance bridges, particularly on the older secondary highway systems and rail underpasses. While Interstate 94 and Interstate 29 generally accommodate 16-foot heights, some structures are lower. The NDDOT requires carriers to perform their own route surveys for loads exceeding 17 feet 6 inches. The carrier is legally responsible for any damage caused to state property, even if traveling on a permitted route. Utilizing advanced routing software to cross-reference the NDDOT Bridge Data ensures that the 100+ restricted structures across the state do not cause a collision or a forced detour that wastes fuel and time.

Sources

North Dakota Department of Transportation Motor Carrier Division (2024) — https://www.dot.nd.gov/divisions/motorcarrier/ North Dakota Legislative Assembly - Century Code Chapter 39-12 (2023) — https://www.ndlegis.gov/cencode/t39c12.pdf FMCSA State Weight Limits (2024) — https://ops.fhwa.dot.gov/freight/policy/rpt_congress/truck_sw_limits/app_a.htm

Frequently asked

What is the maximum width allowed without an escort in North Dakota?

On most state highways, you can travel without an escort up to a width of 14 feet 6 inches. Once you exceed 14 feet 6 inches, a rear escort is required on two-lane roads.

How much does a North Dakota single-trip overweight permit cost?

A standard single-trip permit for an overweight load is $20. If the load exceeds 150,000 pounds, additional ton-mile fees are applied based on the total weight and distance traveled.

Are oversized loads allowed to move at night in North Dakota?

Generally, no. Oversized loads are restricted to daylight hours. However, loads that are overweight but maintain legal dimensions (8'6" wide, 14' high) are allowed 24-hour travel.

Does North Dakota require a flagger for wide loads?

Flaggers are not standard for all wide loads but may be required by the NDDOT for specific movements involving extreme widths or when crossing narrow bridges where two-way traffic is impossible.

How do I check current spring load restrictions in North Dakota?

You must check the NDDOT Travel Information Map or the dedicated Load Restrictions section on the NDDOT website, which is updated daily during the spring thaw period.