Semi Truck Weight Limits by State 2026: GVW, Axles & Bridge Formula
Federal interstate rules set an 80,000 lb gross baseline — but axle groups, bridge formula, and state exceptions decide whether your load is legal or a permit problem.
80k lb
Federal GVW baseline
20k / 34k
Steer / tandem typical
Bridge
Formula still binds
Permits
State-by-state O/W
Key Takeaways
- Federal baseline on the Interstate System is typically 80,000 lb GVW with axle and bridge-formula caps.
- Steer ~12,000–20,000 lb and tandem ~34,000 lb are common reference points — confirm your configuration.
- Bridge formula can make a legal-looking GVW illegal if axles are spaced wrong.
- State exceptions (harvest, divisible vs non-divisible, designated highways) change the math.
- Overweight permits are state-issued and route-specific — multi-state moves need multi-state permits.
- Pair weight planning with height and length — see related equipment guides before you bid.
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 TruckingSemi Truck Weight Limits by State 2026: GVW, Axles & Bridge Formula
Federal Interstate Baseline (Start Here)
On the Interstate System, the familiar package is 80,000 lb GVW, single-axle and tandem-axle caps, and the Federal Bridge Formula. That is the default brokers quote against — and the default scale officers enforce unless you have a valid permit for a higher package.
Empty tractor weight matters because payload = legal GVW minus tractor, trailer, fuel, and gear. See how much a semi weighs before you promise a shipper 45,000 lb on a heavy day cab + reefer.
| Limit type | Typical interstate reference | Why it bites |
|---|---|---|
| GVW | 80,000 lb | Total combination weight |
| Steer / single | Often ~12k–20k depending on setup | Front axle overload |
| Tandem | ~34,000 lb common | Drive or trailer group |
| Bridge formula | Spacing-based max | Short wheelbase illegal even under 80k |
Axle Groups & Bridge Formula
Bridge formula limits how much weight you can put on a group of axles based on spacing. Sliding tandems and fifth-wheel position are your tools — see sliding tandems weight distribution and axle weight limits. A scale ticket that shows "GVW OK" can still fail an axle group.
Do not chase GVW alone
How States Differ (Without Memorizing 50 Codes)
Designated heavy networks
Some states allow higher GVW on posted corridors with permits or annual packages.
Harvest / seasonal
Commodity and season rules can raise limits temporarily — paperwork still required.
Divisible vs non-divisible
Overweight permits often require non-divisible loads; sand and grain may not qualify.
Local bridges & roads
County and municipal limits can be far below interstate — GPS truck routing is not optional.
Always verify the specific state DOT overweight / oversize pages for your route. Pair with legal truck height by state and flatbed weight limits when the freight is dimensional.
When Overweight Permits Are Required
If any state on the route exceeds legal GVW, axle, length, width, or height, you need that state's permit (and often a specific route). Multi-state O/O moves mean multi-state permits — one permit does not travel. Budget permit cost and wait time into the rate con.
Quote with scale risk priced in
Pre-Trip Weight Ops Checklist
Know empty weights
Tractor + trailer + fuel + pallets + securement.
Plan axle positions
Fifth wheel and tandems set before you leave the dock.
Confirm state package
Interstate vs state highway vs local last mile.
Carry permit docs
Cab copies + electronic backups; know escort rules if any.
Frequently Asked Questions
What is the legal semi truck weight limit in the US?
On most Interstate highways the federal baseline is 80,000 lb GVW plus axle and bridge-formula limits, unless a state permit or special network allows more.
Do all states use 80,000 lb?
Many mirror the federal interstate package, but states can authorize higher weights on designated roads with permits or special rules.
What is the bridge formula?
A federal formula that caps weight on axle groups based on spacing — it can make an 80,000 lb load illegal if axles are too close.
Can I run overweight without a permit if I stay off the Interstate?
No. State and local roads have their own limits; many are stricter. Permits are still required when you exceed them.
How do sliding tandems help?
They shift trailer axle weight forward or aft to keep groups under limits — they do not create extra legal GVW.
Related: semi weight, flatbed weight limits, GVWR CDL requirements, legal height, oversize/overweight permits
How Our Team Helps
At O Trucking LLC, we treat compliance, equipment fit, and dispatch paperwork as load-winning fundamentals — not afterthoughts.
Weight-aware dispatch
We decline freight that cannot make scale on your equipment.
Permit freight screening
Only book O/W when permits and rates pencil.
Partner checks
Authority and safety screens before you burn miles.
Ready for loads that fit your setup?
Need Freight That Makes Scale?
Flat weekly dispatch that respects weight and equipment limits. Start at /get-started/.