Iowa oversize permit requirements
Iowa runs one of the most permissive routine permit regimes in the country. Eighteen feet of width and eighteen feet of height as ordinary business, with a hundred and twenty feet of length — figures that would be a superload application in half the states around it. For a wide, tall load moving east to west, Iowa is rarely the state that causes the problem.
It is equally generous about hours, and the threshold is the thing to remember. A load within a hundred feet of length, eleven feet of width and fourteen feet six of height may travel round the clock, seven days a week. Anything larger falls back to the daylight window, half an hour either side of sunrise and sunset, weekends included. Eleven feet is a usefully high bar — a great many machinery moves sit under it.
The restrictions are modest by comparison: I-235 through Des Moines closes at peak, morning and evening, on weekdays, and the holiday calendar is worth checking before a long-weekend move. The permit runs five days. One practical detail that trips up first-time movers: the signage thresholds are lower than the permit thresholds, so Oversize Load signs are required past seventy-five feet of length, eight feet six of width or fourteen feet four of height — a load can need signs before it needs a permit.
Legal dimensions
At or under these figures, no oversize permit is required in Iowa.
- Width
- 8′6″
- Height
- 13′6″
- Gross weight
- 80,000 lb
- Single axle
- 20,000 lb
- Tandem
- 34,000 lb
- Tridem
- 42,000 lb, at 8′1″ minimum axle spacing
Routine permit limits
Above legal dimensions and up to these figures, Iowa issues a permit as routine business. Beyond them the load becomes a superload, reviewed case by case.
- Length
- 120′
- Width
- 18′
- Height
- 18′
- Single axle
- 20,000 lb
- Tandem
- 46,000 lb
- Tridem
- 60,000 lb
- Quad
- 80,000 lb
Escort requirements
A load reaching any of these figures needs an escort in Iowa — the figure is the first size that requires one, so a load measuring exactly this much already needs it.
- Width
- 12′1″
- Height
- 14′4″
- Length
- 120′1″
When the load may move
Permit validity. Permits are valid for five days.
Operating time. A load within 100′ long, 11′ wide and 14′6″ high may travel round the clock, seven days a week. Larger loads run daylight only — half an hour before sunrise to half an hour after sunset — weekends included.
Restricted travel. I-235 through Des Moines closes to oversize movement 7–9 AM and 4–6 PM, Monday to Friday. Holiday and holiday-weekend restrictions apply and should be checked before the move.
Worth knowing
- The 18′ routine width and height are among the most generous in the country — loads that would be superloads elsewhere are ordinary business here.
- Legal trailer length is 53′.
- Oversize Load signs are required past 75′ of length, 8′6″ of width or 14′4″ of height — thresholds lower than the permit ones, so a load can need signs before it needs a permit.
- The quad allowance of 80,000 lb equals the entire legal gross weight of a standard combination.
Iowa permits, answered
How wide and tall can a load be on an Iowa routine permit?
18′ in both dimensions, with 120′ of length. Those are among the most generous routine limits anywhere — several neighbouring states would treat the same load as a superload.
Can an oversize load travel round the clock in Iowa?
Yes, within 100′ of length, 11′ of width and 14′6″ of height — seven days a week. Above any of those the daylight window applies.
When is I-235 closed to oversize loads?
7–9 AM and 4–6 PM on weekdays, through Des Moines. It is the state's main urban restriction.
Do I need Oversize Load signs if I do not need a permit in Iowa?
Possibly. Signs are required past 75′ of length, 8′6″ of width or 14′4″ of height, and those thresholds sit below the permit ones — so yes, a load can legally need signs without needing a permit.
How long is an Iowa oversize permit valid?
Five days.
Crossing more than Iowa?
A permit is per state. If the route leaves Iowa, these are the states it most likely enters.
Get a permit quote for Iowa
Enter the load once and the estimator prices every state on the route, flags where an escort is required, and turns the quote into an order.
Price a permit for Iowa →Compiled from published state DOT sources. Regulations change — confirm the current rules before dispatch. Last reviewed 2026-07-30.