Move a load that is too wide, too tall, too long, or too heavy and you cannot just hit the highway — you need a permit, and usually a different one in every state you pass through. Permitting is where a lot of oversized moves go sideways: wrong route, missing escort, travel-time violation. Here is what you need to know before the wheels turn.
The legal limits — and where permits start
On most U.S. highways, a load is "legal" (no permit) when it stays inside these limits:
Standard legal limits
Width: 8 feet 6 inches · Height: 13 feet 6 inches (14 feet in some western states) · Length: ~48–53 feet for the trailer · Weight: 80,000 lbs gross, with axle and bridge-formula limits underneath it.
Exceed any single one of those and the load is oversize and/or overweight — and it needs a permit for every jurisdiction it travels through.
Types of permits
- Single-trip permits. Issued for one specific load on one specific route, valid for a few days. The most common type for a one-off oversized move.
- Annual / blanket permits. For carriers that regularly run loads within set dimensions; cheaper per trip but limited to defined limits and routes.
- Superload permits. For extreme dimensions or weight. These can require engineering review, bridge analysis, and a longer lead time — days to weeks, not hours.
Escorts, pilot cars, and police
The wider and taller the load, the more eyes it needs on the road. Thresholds vary by state, but as a rule:
- Pilot/escort vehicles are commonly required once a load passes roughly 12 feet wide, with a second escort added for greater widths or long lengths.
- Height poles ride the front escort to check overpass and utility-line clearances on tall loads.
- Police escorts can be required for the widest loads or for travel through major metro areas.
Travel restrictions you can't ignore
A permit is not a blank check to drive whenever you want. States restrict oversized travel during:
- Night hours — many oversize loads can only move during daylight.
- Rush hour in and around metro areas.
- Weekends and holidays — a number of states curtail or ban oversized travel on holiday weekends.
- Bad weather — high winds will shut down a tall or wide load.
Loads also need proper "OVERSIZE LOAD" banners, red/orange flags, and lights, and overweight loads may be routed around weight-restricted bridges entirely.
Who handles all this?
We do. Permitting, route surveys, clearance checks, and escort coordination are part of every heavy haul move we run — across all 48 of our locations and all 50 states. You tell us the load and the lane; we make sure it is legal on every mile. Curious what the permits add to the price? See how heavy haul cost is calculated.
Send us your load and route and we'll handle the paperwork.