Oversize load permits: when you need one and how to get it
No federal agency issues oversize or overweight permits. Each state on your route does, with its own limits, signs, escort rules, and travel windows, so one load can need several permits.
The federal baseline in numbers
You need an oversize load permit when your vehicle and load exceed the legal size or weight limits of any state you drive through, such as 102 inches wide or 80,000 pounds on the Interstate. States issue the permits, not FMCSA, so a multistate move needs one from each state.
Federal law sets the baseline for truck size and weight, and stops there. The permit, the route, the hours you can move, and the escorts and signs you need all come from the states, and they rarely match.
This guide covers what applies everywhere and uses Texas and Florida to show how far state rules differ. For single states in depth, see our guides to Florida oversize permits and New Mexico truck permits.
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Key takeaways
States issue oversize permits, not FMCSA
Federal rules set Interstate and National Network limits. Each state decides who gets a permit and on what terms.
The load usually has to be nondivisible
Splitting it would ruin its use or value, or take more than 8 work hours to dismantle.
Height is a state number
There is no federal height limit. Texas allows 14 feet without a permit; Florida allows 13 feet 6 inches.
Flags are federal, signs are state rules
FMCSA requires 18-inch flags on projecting loads. Each state sets the OVERSIZE LOAD sign and where it goes.
Superloads take weeks
Texas wants superheavy applications three to four weeks ahead unless an approved route is already on file.
In this articleContents
When do you need an oversize load permit?
You need an oversize load permit when the vehicle and its load exceed the legal size or weight limits on the road you are using. Federal law fixes the numbers below. States set the rest, including height and weight limits off the Interstate.
| Limit | Federal rule | Where it applies |
|---|---|---|
| Gross weight | 80,000 lbs, or less if the bridge formula requires | Interstate System |
| Single axle | 20,000 lbs | Interstate System |
| Tandem axle | 34,000 lbs | Interstate System |
| Width | 102 inches (108 in Hawaii) | National Network |
| Semitrailer length | States may not set a limit under 48 feet | National Network |
| Height | No federal limit; each state sets its own | All roads |
These weights include all enforcement tolerances, and the Federal Bridge Formula can lower the allowed gross weight when axles sit close together. Axle spacing matters as much as total weight.
State limits vary. Texas allows 14 feet of height and a 59-foot semitrailer in a two-vehicle combination without a permit. Florida caps height at 13 feet 6 inches. Check the legal limits of every state on the route, not just the one where you load.
Who issues oversize load permits, FMCSA or the states?
The states do. FHWA states plainly that the federal government does not issue permits for oversize or overweight vehicles, and it keeps a list of state permit offices so carriers can apply to each one.
Searches for FMCSA oversize load regulations often point at the wrong agency. The size and weight limits are FHWA rules, in 23 CFR Part 658. FMCSA's part is how a projecting load is marked with flags and lamps, covered in the signs section below.
A state permit usually covers state roads only. Florida's rule, for example, says travel on local roads must be authorized by the local authorities, so a delivery on a county road or city street can need one more permit.
Which oversize permit type fits your load?
Most oversize permits are for nondivisible loads. Under 23 CFR 658.5, a load is nondivisible when splitting it would compromise its intended use, destroy its value, or take more than 8 work hours to dismantle. The applicant carries the burden of proof on those hours.
States then sell a handful of permit types. Texas's list shows the common ones:
| Permit type | What it covers | Texas example |
|---|---|---|
| Single trip | One move from a set origin to a set destination, in the hours on the permit | General single-trip: nondivisible loads up to 254,300 lbs; $60, plus a highway maintenance fee over 80,000 lbs |
| Periodic or annual | Repeat moves within set dimensions for a fixed term | 30, 60, or 90-day width or length permits; one-year company or vehicle envelope permits |
| Superload | Loads past routine ceilings, with route and bridge review | Superheavy: over 254,300 lbs, or 200,001 to 254,300 lbs on less than 95 feet of axle spacing |
| Divisible load | Extra weight for specific commodities where state law allows it | Over axle/over gross weight tolerance: 10% over axle, 5% over gross, off the Interstate, $15,000 bond |
Divisible loads are the exception, not the rule. FHWA says states issue divisible-load permits based on grandfather rights or congressional authorization for specific commodities or routes, so don't assume a load you could split will get one.
How long does a superload permit take?
Longer than any other type. TxDMV wants superheavy applications three to four weeks before the permit is needed, unless an approved route is on file, to allow for route approval and bridge or pavement analysis. Texas also needs a route inspection certification on file for loads over 20 feet wide, 18 feet 11 inches high, or 125 feet long.
Florida asks for a vehicle schematic at least 10 business days before the move when any axle exceeds 30,000 pounds or the gross weight reaches 300,000 pounds.
How to get an oversize load permit
Getting an oversize load permit means applying to each state on the route, with the same measurements in every application.
Step 1: Measure the loaded vehicle
Record width, height, length, overhangs, axle weights, and axle spacings with the load on. Texas measures height from the roadbed to the highest point of the load or vehicle, and length from the foremost point to the rearmost point of either.
Step 2: Confirm the load qualifies
Test it against the nondivisible definition and each state's legal limits. A load that is legal in one state and oversize in the next still needs a permit for the next one.
Step 3: Map the route and every jurisdiction on it
List each state, plus any county or city roads. State systems such as Texas's TxPROS build GIS-based routes with real-time restrictions and let customers self-issue many permits.
Step 4: Apply with your USDOT number
Texas checks your USDOT number against FMCSA's MCMIS system for out-of-service orders before it issues a permit. Texas also requires a $10,000 permit surety bond from carriers that don't need a USDOT number, and a shipper's certificate of weight for loads over 200,000 pounds gross.
Step 5: Carry the permit and follow its conditions
The permit covers only the route, dates, and hours on it. A Texas single-trip permit is good for one movement, during the times it specifies, from one origin to one destination. If you would rather not work each state's portal yourself, our oversize permits team can file for you.
What are the oversize load sign requirements?
Oversize load sign requirements come from each state and from your permit, not from one national rule. Federal rules cover flags and lamps on projecting loads; the OVERSIZE LOAD sign, its size, and where it goes are state rules.
What federal rules require
- Flags: a load extending more than 4 inches beyond the sides or 4 feet beyond the rear needs red or orange fluorescent flags, at least 18 inches square, at its extremities (49 CFR 393.87).
- Flag count: one flag at the extreme rear if the projection is 2 feet wide or less, two if it is wider.
- Lamps at night: side projections over 4 inches need an amber lamp at the front edge and a red lamp at the rear edge; rear projections over 4 feet need red side marker lamps plus two red lamps and two red reflectors on the rear (49 CFR 393.11).
How state sign and escort rules differ
The same load can need different equipment one state line later. Texas and Florida show the spread:
| Rule | Texas | Florida |
|---|---|---|
| Legal height without a permit | 14 ft | 13 ft 6 in |
| OVERSIZE LOAD sign | On escort vehicles: yellow, 5 to 7 ft long, 12 to 18 in high, 8 to 10 in letters | On loads over 10 ft wide, 80 ft long, or 14 ft 6 in high: at least 7 ft by 18 in, 12 in letters |
| Flags on the load | 12 in red flags at the load's extremities | At least 18 by 18 in, on all four corners and every projection |
| First escort for width | Over 14 ft | Over 12 ft |
| Escort with a height pole | Over 17 ft | Over 14 ft 6 in |
Where rules overlap, meet the stricter one. An interstate carrier under FMCSA's rules needs 18-inch flags even in Texas, and an 18-inch flag also satisfies the Texas rule.
How do you plan an oversize move across several states?
Plan a multistate oversize move around its strictest state, because the load has to be legal or permitted in every one. Build one timeline that shows each state's permit, movement hours, and blackout days.
- Holidays: Texas bars loads over 14 feet wide, 16 feet high, or 110 feet long on six holidays; Thanksgiving (November 26), Christmas Day, and New Year's Day 2027 are still ahead. Florida's rule bars weekend and holiday moves unless the permit says otherwise.
- Escorts: Texas accepts escort flagger training that another state accepts. Florida accepts escorts qualified by another state only if that state's standards are equal or stricter and the escort qualified within the past four years.
- Other credentials: an oversize permit covers size and weight only. A truck without an IFTA license still needs a temporary fuel permit, and interstate carriers need a current UCR registration.
For the full list of registrations and permits an interstate truck carries, see truck permits explained.
How Simplex helps with oversize load permits
Oversize permits are bought one state at a time. We help you get each one right and line them up before the load moves.
Oversize permits in every state
Our oversize permits team handles oversize, overheight, overwidth, overlength, and heavy haul permits across all 50 states, determines each state's requirements, and helps plan the route around distance, permit turnaround, and safety.
Every other permit on the trip
Our trucking permits service identifies the permits you need for each state, including temporary fuel and trip permits, and handles the paperwork start to finish.
UCR filed and renewed
Interstate carriers still need UCR alongside their oversize permits. Our UCR service helps you file or renew it.
Frequently asked questions
Does FMCSA issue oversize load permits?+
How big does a load have to be to need an oversize permit?+
What size is an oversize load sign?+
What is a superload permit?+
What is the over axle and over gross weight tolerance permit bond?+
Is there one oversize permit that covers every state?+
Where this information comes from
The requirements below come from federal regulation, FHWA, the Texas Department of Motor Vehicles, and the Florida Administrative Code, checked on September 24, 2026.
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1
FHWA — Oversize/Overweight Load Permits
The federal government issues no OS/OW permits; nondivisible and divisible load rules; state permit contacts.
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2
eCFR — 23 CFR 658.17
Interstate weight limits, the bridge formula, tolerances, and state permits for nondivisible loads.
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3
eCFR — 23 CFR 658.15
The 102-inch width limit on the National Network and state permits for wider vehicles.
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4
eCFR — 49 CFR 393.87
Warning flags on loads projecting beyond the sides or rear.
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5
FHWA — Federal Size Regulations for Commercial Motor Vehicles
No federal height limit; states set their own.
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6
TxDMV — Texas Size/Weight Limits
Texas legal and permitted dimensions, measurement rules, and holiday size limits.
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7
TxDMV — Escort and Equipment Requirements
Texas escort thresholds, flags, lights, escort signs, and flagger training.
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8
Florida Administrative Code — Chapter 14-26
Florida signs, flags, escorts, holiday and weekend rules, local roads, and schematics.
Written by
Simplex Group
Permits & Fuel Tax Team, Simplex Group
Reviewed for technical accuracy by a Simplex permitting manager before publication. Simplex has registered and filed permits and fuel taxes for interstate carriers across all 50 states for more than 20 years.
Published · Updated
Related articles and services
Permit every state on the route before the wheels turn
An oversize move is only as legal as its weakest state. One missing permit, a holiday you didn't check, or an escort that doesn't meet the next state's rules can stop the load mid-route.
If you want help sorting the permits, route, and conditions for your next oversize load, talk to our team.