Legal Truck Height by State 2026: 13 ft 6 in Rules & Exceptions
Most US corridors live around a 13'6" legal height - but exceptions and bridge realities still kill loads. Confirm state rules and your actual loaded height before you roll.
13'6"
Common legal height
State
Exceptions exist
Measure
Loaded height
Permit
When you exceed
Key Takeaways
- 13'6" is the common baseline - not a universal law for every road.
- Some states allow higher on certain networks; others are stricter.
- Measure loaded height - do not trust estimates.
- Bridge clearances can be lower than legal maximums.
- Over-height requires permits and routing.
- Step-decks help but do not erase legal caps.
Ahmad Qazi
Founder & CEO, O Trucking LLC
Fact-Checked by O Trucking Dispatch Team
5+ years helping carriers with rates, authority, and compliance
Sources:
Written by Ahmad Qazi, founder of O Trucking LLC, drawing on 9+ years dispatching for owner-operators. Learn more about us.
O TruckingLegal Truck Height by State 2026: 13 ft 6 in Rules & Exceptions
The Common 13'6" Baseline
Many drivers plan around 13'6" overall loaded height on Interstates. That habit is useful - but it is not a substitute for checking the states and bridges on your specific path.
Why By-State Still Matters
Network differences
State highways vs Interstate vs local
Posted clearances
Bridges lower than legal max
Seasonal / construction
Temporary restrictions
Special corridors
Some allow higher with conditions
Pair height rules with equipment choice: step-deck clearance vs flatbed dimensions.
How to Measure Loaded Height
Measure from ground to highest point after loading and tarping. Include exhaust stacks, AC units, and tarps. Write it on the bill of lading notes for your own protection.
Legal max is not a clear path
When You Need Over-Height Permits
If loaded height exceeds a state's legal limit for your road class, you need the proper oversize permit and an approved route. Dispatch should flag this before acceptance - especially on machinery freight.
Keep a state cheat sheet
Frequently Asked Questions
What is the legal truck height in most US states?
Many states use about 13 feet 6 inches as a common legal height on major highways, but you must confirm each state and road class on your route.
Can I run taller than 13'6" without a permit?
Only if the states and road networks on your route legally allow it. Otherwise you need over-height permitting and routing.
Do bridges always clear legal height?
No. Posted clearances can be lower than the legal maximum. Route for the lowest bridge on the path.
How do I measure truck height?
Measure from the ground to the tallest point of the loaded combination, including tarps and equipment on top.
Does a step-deck avoid height permits?
It can help you stay under legal height by lowering the deck, but it does not allow illegal over-height without permits.
Related: step-deck clearance, flatbed dimensions, semi weight, 53 ft dry van, weight limits by state.
How Our Team Helps
At O Trucking LLC, we treat compliance, equipment fit, and dispatch paperwork as load-winning fundamentals — not afterthoughts.
Height-aware dispatch
We ask loaded height before committing tall freight.
Equipment matching
Flats vs step-decks based on real clearance.
Permit awareness
We flag over-height risk early.
Ready for loads that fit your setup?
Running Tall or Tight Clearance Freight?
Tell us your loaded height - free consult at /get-started/.