Alabama Oversize and Overweight Permitting Guide

Operating oversize or overweight (OS/OW) loads in Alabama requires strict adherence to regulations set by the Alabama Department of Transportation (ALDOT). The state classifies any vehicle exceeding 8 feet 6 inches in width, 13 feet 6 inches in height, or 80,000 pounds in gross vehicle weight as needing a special permit. Alabama is a member of the Southeastern Association of State Highway and Transportation Officials (SASHTO), which allows for some regional permit uniformity, but specific state statutes under Code of Alabama Title 32 govern the majority of local movements. Transporters must obtain these permits before entering the state or moving the load, as roadside enforcement by the Alabama Law Enforcement Agency (ALEA) is rigorous. Carriers can simplify this regulatory burden by using DispatchTool to manage route planning and documentation. The platform provides truck-safe routing that accounts for Alabama’s specific vertical clearances and bridge weight ratings, ensuring drivers stay on permitted corridors. By centralizing permit copies and load specifications, DispatchTool helps dispatchers verify that every OS/OW movement complies with ALDOT requirements before the wheels turn. To streamline your fleet’s compliance and routing workflow, create a DispatchTool account.

Alabama Legal Dimensions and Weight Limits

Before a permit is required, a vehicle must exceed legal dimensions defined by ALDOT. The maximum legal width is 8 feet 6 inches, and the maximum legal height is 13 feet 6 inches. Legal length for a single unit is 40 feet, while a tractor-trailer combination is generally limited to 60 feet on non-designated highways, though 53-foot trailers are standard on the Interstate system. The maximum gross weight without a permit is 80,000 pounds, distributed across a maximum of 20,000 pounds for a single axle and 34,000 pounds for a tandem axle. Exceeding any of these thresholds by even one inch or one pound necessitates an OS/OW permit.

Types of Permits and Associated Fees

Alabama offers several permit types based on the frequency and nature of the haul. A Single Trip Permit is valid for 5 days and typically costs $20 for oversize only, or starts at $20 plus weight-based fees for overweight loads. For frequent shippers, Annual Permits are available at $100 for oversize loads up to 12 feet wide and 75 feet long. Overweight annual permits cost $500 but are restricted to specific commodities like sealed containers or agricultural products. ALDOT also charges a $10 issuance fee for every permit processed through their online system. Fees must be paid via a pre-established escrow account or credit card at the time of application.

Escort Requirements and Pilot Cars

Escort vehicle requirements in Alabama are triggered primarily by width. One rear escort is required for loads exceeding 12 feet wide on four-lane highways. If the width exceeds 14 feet, two escorts (front and rear) are mandatory on two-lane roads. For loads over 15 feet 6 inches wide, a police escort may be ordered at the discretion of ALDOT or the Alabama Law Enforcement Agency. Height-based escorts are required if a load exceeds 15 feet 6 inches, necessitating a front escort with a height pole. All pilot cars must be equipped with two-way radios and amber flashing lights visible from 360 degrees.

Operating Hours and Holiday Restrictions

Standard oversize movements in Alabama are permitted from thirty minutes before sunrise to thirty minutes after sunset, Monday through Saturday. Sunday travel is generally prohibited for loads exceeding 12 feet wide or 100 feet long. Furthermore, ALDOT restricts OS/OW travel during major holidays including New Year’s Day, Memorial Day, Independence Day, Labor Day, Thanksgiving Day, and Christmas Day. In high-traffic areas like Birmingham, Mobile, and Montgomery, ALDOT may impose 'curb hours' which restrict movement between 7:00 AM – 9:00 AM and 4:00 PM – 6:00 PM to avoid peak commuter congestion.

Superload Criteria and Processing

Alabama defines a 'Superload' as any vehicle and load combination that exceeds 16 feet in width, 16 feet in height, 150 feet in length, or 250,000 pounds in gross weight. These applications require a more intensive review process, often taking 5 to 10 business days. Applicants must submit a detailed axle spacing diagram and may be required to pay for a structural bridge analysis if the weight exceeds specific capacities on the proposed route. The fee for a superload varies significantly based on the work required by ALDOT engineers to verify route safety.

Mobile Home and Manufactured Housing Rules

Alabama has specific statutes for the movement of manufactured homes. Units up to 14 feet wide require a standard permit, but units between 14 feet and 16 feet wide are subject to 'Mega-load' rules which include mandatory escorts and specific speed restrictions (usually 55 MPH or lower). The towing vehicle must have a minimum GVWR of 35,000 pounds and at least three axles to pull a 16-foot wide unit. Signs measuring 7 feet by 18 inches with the words 'OVERSIZE LOAD' must be mounted on the front of the towing vehicle and the rear of the mobile home.

Sources

Alabama Department of Transportation (ALDOT) Permit Manual (2024) — https://www.dot.state.al.us/mntc/overweightPermits.html Code of Alabama Title 32 - Motor Vehicles and Traffic (2023) — https://alison.legislature.state.al.us/code-of-alabama ATRI Alabama State Laws and Regulations (2024) — https://truckingresearch.org/

Frequently asked

What is the maximum weight allowed on a tandem axle with a permit?

With a routine overweight permit, Alabama generally allows up to 44,000 pounds on a tandem axle, provided the tires are rated for the load and the gross weight does not exceed the permit's limits.

How long is a single-trip permit valid in Alabama?

A single-trip permit is valid for 5 days. If a delay occurs due to weather or mechanical failure, you must contact the ALDOT Permit Office before the permit expires to request an extension.

Are flags and lights required for daytime oversize moves?

Yes, red or orange fluorescent flags at least 18 inches square must be placed at the four corners of the extremities of any wide load, and at the end of any load overhanging more than 4 feet.

Does Alabama accept the SASHTO regional permit?

Yes, Alabama is a participating member of SASHTO, allowing for a single permit application for multi-state moves within the southeast for loads up to 14 feet wide, 14 feet high, and 100 feet long.

Can I move an oversize load on the interstate at night?

Night movement is generally prohibited for oversize loads in Alabama unless specifically authorized for emergency repairs or by special permit provision for loads that do not exceed 10 feet wide.