Over 80,000 lbs, over 8′6″ wide, over 13′6″ tall, over 53′ trailer length? You’re in permit territory. State permits, escort vehicles, route surveys, bridge ratings, and superload engineering — coordinated across all 48 states for industrial, energy, construction, agricultural, and infrastructure shippers.
📞 Get Oversize Rate: (786) 574-5774 ✉ rates@ship-ati.com| Dimension | Federal Maximum | Source |
|---|---|---|
| Gross Vehicle Weight | 80,000 lbs on Interstate | 23 CFR 658.17 |
| Single-axle weight | 20,000 lbs | Federal Bridge Formula |
| Tandem-axle weight | 34,000 lbs | Federal Bridge Formula |
| Width | 8′6″ (102″) | 23 CFR 658.15 |
| Height | 13′6″ common, 14′ in some states | State law (no federal limit) |
| Length (single trailer) | 53′ common; varies by state | State law |
| Length (twin trailers) | 28′6″ per trailer on Interstate | STAA |
Anything outside the dimensions above. The most common OS/OW shipments are:
Issued for one specific move with specific origin, destination, and route. Most common for one-off OS/OW shipments. Per-state cost typically $25 to $400 depending on size, weight, and state. Multi-state moves stack permits from every state on the route.
Valid for repeated moves within defined dimension and weight envelopes for a year. Useful for shippers running regular OS/OW within a state (logging, construction, agricultural fleets). Costs $300 to $2,000 per state typically.
Required for loads exceeding the state’s superload threshold. Engineering analysis of bridges along the proposed route, structural review, and often state police coordination. Lead time 2 to 6 weeks. Cost $500 to $5,000+ per state depending on engineering scope.
Permitted OS/OW loads typically can’t move during all hours. State-specific rules cover:
Multi-state permits · Escorts · Route surveys · Superloads
Escort vehicles travel ahead of and behind the OS/OW load to warn traffic, manage lane changes, and verify clearances. Requirements vary by state but follow a general pattern:
| Load Dimension | Escort Typical Requirement |
|---|---|
| > 12′ wide | 1 escort (front or rear depending on route) |
| > 14′ wide | 2 escorts (front + rear) |
| > 16′ wide | 2 escorts + sometimes state police |
| > 14′ tall | Height pole-car (high-pole escort) |
| > 100′ long | 2 escorts |
| > 150′ long | 2 escorts + state police on some routes |
| Superload | Multiple escorts + state police mandatory |
Escort vehicle drivers are certified by the state (Texas, Louisiana, Florida, and several others have formal certification programs). Pole-car drivers carry a calibrated height pole at the load’s actual height for clearance verification at every bridge, sign, and overhead obstruction along the route.
Above a certain weight or footprint, the carrier or shipper must perform a route survey before the permit is issued. The survey identifies every bridge, overpass, traffic signal, sign, and obstruction along the proposed route, verifies the load can clear each, and confirms each bridge’s rated capacity is sufficient for the gross weight and axle distribution.
For superloads, state DOT bridge engineers review the survey and may approve, modify the route, or require sub-route engineering work (e.g., temporarily reinforcing a bridge). This process consumes most of the permit lead time and is non-negotiable. Skipping it is how you end up with a load stuck under a bridge that doesn’t clear — or worse.
Need NMFC class for the underlying commodity? Use the ATI freight class calculator.
ATI coordinates oversize and overweight freight nationwide including multi-state permits, escort vehicles, route surveys, and superload coordination. Construction, agriculture, energy, infrastructure, and industrial shippers use ATI for OS/OW where standard freight isn’t an option.
Call (786) 574-5774 or email rates@ship-ati.com.
Permits, escorts, routes, superloads. Coordinated across 48 states.
📞 (786) 574-5774 ✉ rates@ship-ati.com