What a superload actually is
A superload is not a bigger oversize permit. It is a different process. Below a state’s superload line, a permit is an administrative act — you apply, the system checks your numbers against a table, and a permit comes back. Above that line, the state stops treating your load as paperwork and starts treating it as an engineering problem: which bridges will carry it, which overpasses it fits under, which turns it can physically make.
That is why the word matters even though no two states define it the same way. Crossing the line changes the lead time, the documentation, and often the escorts — not just the fee.
You can be a routine oversize load in one state and a superload in the next one on the same trip. A 16-foot-wide load is under the line in the 20 states that trigger at 16 feet, and over it in the seven that trigger lower. Plan to the strictest state on the route, not the one you load in.
Where each state draws the line
Four dimensions can push a load into superload review, and states do not agree on any of them. Width is the most commonly published trigger; weight is the most commonly published overall.
| Superload at | States | Notes |
|---|---|---|
| 14′0″ | 2 | The strictest line in the country — barely over a legal-width-and-a-half load. |
| 14′6″ | 1 | |
| 15′0″ | 5 | |
| 16′0″ | 20 | The most common figure, and the one worth memorising. |
| 16′6″ | 2 | |
| 17′0″ | 4 | |
| 18′0″ | 2 | The most permissive published line. |
| Not published | 12 | No table figure. Decided when you apply, on the route you give them. |
Of the four dimensions, weight is published by the most states — 39 of 48 — and it is where the spread is widest. Some states start superload review at 120,000 lb gross; others not until 500,000 lb. Height triggers are published by 31 states and cluster at 16 feet. Length is published by 29.
- Width trigger
- 36 of 48
- Weight trigger
- 39 of 48
- Height trigger
- 31 of 48
- Length trigger
- 29 of 48
Superload triggers, all 48 states
Exceed any one of these and the load goes to review in that state. Where a cell says Not published, the state has no figure in its published tables — it is decided on application. That is not the same as no limit.
| State | Width | Height | Length | Gross weight | Review |
|---|---|---|---|---|---|
| Alabama | 16' | 16' | 150' | 300,000 lb | 3 days |
| Arkansas | 16'6" | 15'6" | 100' | 180,000 lb | Not published |
| Arizona | 16' | 16' | 120' | 250,000 lb | 14 days |
| California | 15' | 17' | 135' | Not published | 30 days |
| Colorado | Not published | Not published | Not published | 500,000 lb | 5 days |
| Connecticut | 16' | 16' | 150' | 200,001 lb | 5 days |
| Delaware | 15' | 15' | 120' | 120,000 lb | 14 days |
| Florida | 16' | 18' | 150' | 200,000 lb | 10 days |
| Georgia | 16' | 16' | Not published | 180,001 lb | Not published |
| Iowa | Not published | Not published | Not published | Not published | Not published |
| Idaho | 16' | 16' | 120' | Not published | Not published |
| Illinois | 14'6" | 15' | 145' | 120,000 lb | Not published |
| Indiana | 16' | 15' | 110' | 120,000 lb | Not published |
| Kansas | 16'6" | 18' | 126' | 150,000 lb | Not published |
| Kentucky | 16' | Not published | 120' | 160,000 lb | Not published |
| Louisiana | Not published | Not published | Not published | 232,000 lb | 28 days |
| Massachusetts | Not published | Not published | Not published | 130,000 lb | 10 days |
| Maryland | 16' | 16' | 100' | 150,000 lb | 2 days |
| Maine | 16' | 15' | 125' | 160,000 lb | Not published |
| Michigan | 16' | 15' | 150' | Not published | 10 days |
| Minnesota | 16' | 16' | 150' | 250,000 lb | Not published |
| Missouri | 16' | 16' | 150' | 160,000 lb | 14 days |
| Mississippi | 17' | 15'7" | 121' | 189,999 lb | Not published |
| Montana | 18' | 17' | 150' | Not published | 2 days |
| North Carolina | 17' | Not published | Not published | 132,000 lb | 14 days |
| North Dakota | Not published | Not published | Not published | 200,000 lb | Not published |
| Nebraska | 16' | 15'11" | 150' | 160,000 lb | 10 days |
| New Hampshire | 15' | 13'6" | 110' | 150,000 lb | 30 days |
| New Jersey | Not published | Not published | Not published | Not published | Not published |
| New Mexico | Not published | Not published | Not published | 170,000 lb | Not published |
| Nevada | 17' | 18' | 200' | 500,000 lb | 10 days |
| New York | 16' | 16' | 160' | 200,000 lb | 10 days |
| Ohio | 14' | 14'6" | Not published | 120,000 lb | Not published |
| Oklahoma | Not published | Not published | Not published | 209,000 lb | Not published |
| Oregon | 14' | 17' | 150' | 900,000 lb | 10 days |
| Pennsylvania | 16' | Not published | 160' | 201,000 lb | Not published |
| Rhode Island | Not published | Not published | Not published | 200,000 lb | Not published |
| South Carolina | Not published | Not published | Not published | 130,000 lb | Not published |
| South Dakota | Not published | Not published | Not published | Not published | Not published |
| Tennessee | 16' | 15'6" | Not published | Not published | Not published |
| Texas | Not published | Not published | Not published | 254,301 lb | 42 days |
| Utah | 17' | 17'6" | Not published | Not published | 14 days |
| Virginia | 15' | 15' | 150' | 115,000 lb | 10 days |
| Vermont | 15' | 14' | 100' | 150,000 lb | 10 days |
| Washington | 16' | 16' | 125' | 200,000 lb | 30 days |
| Wisconsin | 16' | Not published | Not published | 150,001 lb | Not published |
| West Virginia | 16' | Not published | Not published | 120,001 lb | 2 days |
| Wyoming | 18' | 17' | 120' | 160,001 lb | 3 days |
How long review takes
Twenty-six states publish a review window. The other 22 do not, which is itself useful information: those are the states where you should apply earlier than feels necessary, because the answer depends on what the bridge engineers find.
| Review window | States | What it means for planning |
|---|---|---|
| 5 days or less | 7 | Same working week, if nothing on the route needs a survey. |
| 10 days | 9 | The most common figure. Two working weeks is the safe assumption. |
| 14 days | 5 | Plan the load before you book the freight. |
| 28 days or more | 5 | Up to 42 days in the slowest state. These need to be in motion a month out. |
| Not published | 22 | No committed window. Treat as two weeks minimum and ask early. |
The published window is the review, not the trip. It starts when the state has a complete application — dimensions, axle spacings, weights per axle, and the exact route. An incomplete application does not start the clock, which is the single most common reason a superload runs late.
What the review involves
The specifics vary, but a superload review is usually some combination of four things:
- Bridge and structure analysis. The state models your axle weights and spacings against every structure on the route. This is why axle spacing matters as much as gross weight — the same 200,000 lb spread over more axles may pass where a tighter configuration fails.
- Route survey. A physical drive of the route confirming vertical and horizontal clearance. Several states trigger this on dimension alone, not on superload status.
- Escort and police requirements. Superloads commonly pick up requirements beyond the ordinary escort table — additional vehicles, police at specific points, or utility crews for overhead lines.
- Movement restrictions. Tighter windows than a routine oversize permit: off-peak only, weekdays only, or specified hours through metropolitan areas.
Planning a superload move
Three things save the most time, in order:
- Fix the route before you apply. Review is route-specific. Changing the route after submission generally restarts it.
- Have the axle detail ready. Axle count, individual axle weights and spacings, and the tractor configuration. Gross weight alone is not enough for a structure analysis.
- Apply to the slowest state first. On a multi-state route the critical path is whichever state has the longest review, not the first one you enter.
Common questions
What is a superload?
A superload is a load so far over legal size or weight that the state will not issue it as a routine oversize permit. Instead it goes to engineering review. There is no federal definition — each state sets its own trigger, and the numbers are not close to each other. Sixteen feet wide is the most common width trigger, used by 20 states, but the range across the country runs from 14 feet to 18 feet.
At what width does a load become a superload?
Twenty states set the line at 16 feet wide. Five use 15 feet, four use 17 feet, two use 18 feet, two use 14 feet, and single states use 14′6″ and 16′6″. Twelve states publish no width trigger at all, which does not mean there is no threshold — it means it is decided case by case when you apply.
How long does a superload permit take?
Of the 26 states that publish a review window, the shortest is two days and the longest is 42. Ten days is the most common figure. Twenty-two states publish no lead time, so the honest answer for those is that it depends on the route and the bridges on it.
Is a superload permit more expensive?
The permit fee itself is often the same as any oversize permit in that state. The cost comes from what the review requires: route surveys, bridge analysis, escorts, police, and sometimes utility crews to lift lines. Permigo charges the same $20 per state permit either way.
Do I need a route survey for a superload?
Frequently, yes — and in several states it is triggered by dimension rather than by superload status. Texas requires a route survey over 20 feet wide on divided highways, for example. The survey confirms that every overpass, bridge and turn on the route will physically take the load.
Can I run a superload at night?
Usually the opposite. Most states restrict oversize movement to daylight hours, and superloads are commonly held to even tighter windows — off-peak only, weekdays only, or with police escort at specific hours. Check the movement window on your state page.