Maryland Hauling Permits: OS/OW Regulations and Fees

Operating oversize or overweight (OS/OW) loads in Maryland requires strict adherence to the Maryland Department of Transportation State Highway Administration (MDOT SHA) guidelines. The state classifies any vehicle exceeding 8 feet 6 inches in width, 13 feet 6 inches in height, or 80,000 pounds gross vehicle weight as a hauling violation without a specific permit. Maryland is a critical corridor for the I-95 mid-Atlantic region, and the state utilizes the Maryland One (MarylandOne) system for automated permit processing, which analyzes routes against bridge clearances and construction constraints. DispatchTool assists carriers in managing these complex movements by providing truck-safe routing that respects height and weight restrictions recorded in state databases. By centralizing permit documents and route instructions within the platform, drivers can ensure they remain on state-approved corridors such as I-695 or US-50. This integration reduces the risk of bridge strikes or permit violations that result in heavy fines. To streamline your heavy haul compliance and route planning, you can create a DispatchTool account.

Maryland Legal Dimensions and Weight Limits

Before applying for a permit, carriers must understand Maryland's legal non-permitted limits. Under Maryland Code, Transportation § 24-102 and § 24-104, the maximum overall length for a single unit is 40 feet, while a tractor-semitrailer combination is limited by its 53-foot trailer length rather than a total length on designated highways. The legal width limit is 102 inches (8 feet 6 inches), and the maximum height is 13 feet 6 inches. For weight, the maximum gross vehicle weight (GVW) is 80,000 pounds across five axles, with single-axle limits of 20,000 pounds and tandem-axle limits of 34,000 pounds. Any vehicle exceeding these metrics must obtain an OS/OW permit through the Motor Carrier Division.

Permit Types and Associated Fees

Maryland offers several permit categories based on the frequency and nature of the haul. Single-trip permits are valid for 5 days and generally cost $30 for overweight loads up to 45 tons, with an additional $5 for each ton over 45. Oversize-only permits typically cost $30 per trip. For frequent haulers, Maryland provides 30-day permits starting at $60 and annual permits for specific equipment types. A $4.00 service fee applies to most transactions in the MarylandOne system. Extraordinary loads, defined as those exceeding 150,000 pounds or significant dimensions, require an engineering review fee starting at $100 per hour for structural analysis.

Escort Vehicle Requirements (Pilot Cars)

Maryland MDOT SHA mandates escort vehicles based on the dimensions of the load. One escort is required for widths between 13 feet and 14 feet on undivided highways, while two escorts (front and rear) are required for widths exceeding 14 feet. If a load exceeds 16 feet in width or 14 feet 6 inches in height, Maryland State Police (MSP) escorts may be mandated at the carrier's expense, costing approximately $75 to $100 per hour per officer with a 4-hour minimum. Lengths exceeding 85 feet generally require a rear escort on two-lane roads to assist with navigation and blind spots.

Time of Movement and Holiday Restrictions

Movement for permitted loads is generally restricted to 30 minutes before sunrise until 30 minutes after sunset, Monday through Saturday. Maryland strictly prohibits the movement of OS/OW loads on Sundays. Furthermore, travel is restricted on major holidays including New Year's Day, Memorial Day, Independence Day, Labor Day, Thanksgiving, and Christmas. In the Baltimore and Washington D.C. metropolitan areas, curfew hours typically restrict movement between 7:00 AM to 9:00 AM and 4:00 PM to 6:00 PM to prevent interference with peak commuter traffic. Carriers should check the MDOT SHA System Preservation website for daily lane closure updates.

Bridge and Tunnel Restrictions

Maryland is known for specific infrastructure constraints, particularly the Baltimore Harbor (I-95) and Fort McHenry (I-895) Tunnels. No hazardous materials are permitted, and strict height/width limits apply; the Fort McHenry Tunnel has a height limit of 14 feet 6 inches, but permitted loads are often diverted to the Francis Scott Key Bridge (note: check current status due to infrastructure changes) or the I-695 western bypass. The Chesapeake Bay Bridge (US-50/301) has specific wind restrictions; movement is prohibited when sustained winds exceed 40 mph. Loads exceeding 12 feet in width are restricted to specific time windows on the bridge to avoid lane blockages.

Superload Criteria and Engineering Reviews

A 'Superload' in Maryland is defined as any vehicle and load combination that exceeds 150,000 pounds GVW, 16 feet in width, or 16 feet in height. These applications must be submitted at least 10 to 30 business days in advance to allow for a comprehensive structural review by the MDOT SHA Bridge Development Division. The carrier must provide a detailed axle spacing diagram. If the route involves local municipal roads, the carrier is responsible for obtaining separate permissions from local jurisdictions, as the state permit only covers Maryland-maintained highways.

Sources

Maryland Department of Transportation State Highway Administration (2024) — https://www.roads.maryland.gov/mdotsha/pages/index.aspx?PageId=334 Maryland Code, Transportation Title 24 (2024) — https://mgaleg.maryland.gov/mgawebsite/Laws/Statutes American Transportation Research Institute (ATRI) Maryland State Profile (2023) — https://truckingresearch.org/

Frequently asked

What is the maximum weight allowed with a permit in Maryland?

With a standard overweight permit, Maryland allows up to 150,000 pounds GVW without a superload designation, provided the axle weights are distributed according to state formulas. Loads over 150,000 pounds require a special structural review and higher fees.

How much does a single-trip permit cost in MD?

A basic single-trip oversize permit costs $30.00. If the load is overweight, the fee is also $30.00 for the first 45 tons (90,000 lbs), plus $5.00 for each additional ton over that weight.

Are there nighttime travel allowances for OS/OW loads?

Night travel is generally not permitted for oversize loads in Maryland unless specifically authorized by the MDOT SHA for special circumstances, such as extremely large loads that would paralyze daytime traffic, or for moves on the Intercounty Connector (MD 200).

When are Maryland State Police escorts required?

State Police escorts are typically required when a load exceeds 16 feet in width, 16 feet in height, or 100 feet in length, or whenever the MDOT SHA determines the move poses a significant safety risk to the public.

How do I apply for a Maryland hauling permit?

Applications must be submitted through the MarylandOne portal, which is the state's 24/7 online permitting system. Most routine permits are issued automatically if the route is cleared by the system's database.