Iowa Oversize & Overweight Permit Rules
What a load can be in Iowa without a permit, where the permit and escort tiers start on 2-lane roads and multi-lane roads, when it can move, and who to call. Every figure is the JaloPermit Atlas entry for Iowa, shown as the app shows it.
Rules as of Jul 31, 2026 · Links checked Jul 13, 2026
Read this before you trust a number. Rules change. The issued permit, posted signs and the state permit office always win over this page. JaloPermit is a reading aid, not a permit-filing service. Guests get 3 free decodes a day with no account and no card, logged-in users get 10 a day, and extra decodes are $3.50 each with no subscription.
What moves in Iowa without a permit
Legal limits are the dimensions and gross weight a vehicle may run at without an oversize or overweight permit. Iowa publishes its length limit as semitrailer, so compare it against that measurement on your permit, not the overall rig.
Where the permit and escort tiers start
| Dimension | Legal without permit | Permit tier starts | First escort on 2-lane roads | First escort on multi-lane roads |
|---|---|---|---|---|
| Width | 8'6" | 8'7" | 12'1" · Front escort or amber light | 12'1" · Rear escort or amber light |
| Height | 13'6" | 13'7" | 14'7" · Front + High pole | 14'7" · Front + High pole |
| Length | 53'0"semitrailer | 75'1" | 120'1" · Rear escort | 120'1" · Rear escort |
| Weight | 80,000 lbs | 80,001 lbs | No escort tier (permit only) | No escort tier (permit only) |
"Permit tier starts" is the lowest size in the Atlas ladder that needs a permit. "First escort" is the lowest size that adds a private or police escort on that road class; the full ladder with each tier's rule and source is below.
Iowa escort ladder, tier by tier
Open a tier to read the rule behind it, quoted with its source. Amber tiers add a police escort or a superload review; grey tiers are permit-only with conditions.
On 2-lane roads
Escorts begin at 12'1" wide
Width
Permit required8'7" – 12'
Over 8'6" up to 12'0": permit, flags and Oversize Load signs required. No lights or escorts.
Front escort or amber light12'1" – 14'6"
Over 12'0" up to 14'6" on 2-lane roads: one front escort, OR, in lieu of the escort, an amber or strobe light on the power unit and on the rear extremity of the vehicle or load. Flags and OVERSIZE LOAD signs are required. The permit-issuing authority may require additional escorts. Source: Iowa Admin. Code 761-511.20(2) (escort chart and asterisk note) and 511.20(4). An amber warning light may replace the front escort. Source: Iowa Admin. Code 761-511.20(2) chart and footnote (ARC 9512C).
Front escort14'7" – 16'6"
Over 14'6" to 16'6": front escort required. No lights-in-lieu option on 2-lane at this width.
Front escort16'7" – 18'
Over 16'6" to 18'0": front escort required.
Front escort18'1"+
Over 18'0" is beyond the published chart. Escorts are set by the permit-issuing authority, which may require additional escorts. Above 20 ft, this row's escorts are the minimum; the permit sets any more.
Height
Permit required13'7" – 14'6"
Over 13'6" to 14'6": permit, flags and Oversize Load signs required. No escort.
Front + High pole14'7"+
Over 14'6" to 20'0": front escort with a mounted height pole. The escort measures all vertical clearances. Above 20 ft, this row's escorts are the minimum; the permit sets any more.
Length
Permit required75'1" – 85'
75'1" to 85'0" overall: flags and Oversize Load signs required. No lights or escorts.
Permit required85'1" – 120'
Over 85' to 120' overall: flags, signs and amber warning lights required. No escort.
Rear escort120'1"+
Over 120' overall: rear escort required. Above 200 ft, this row's escorts are the minimum; the permit sets any more.
Weight
Permit required80,001 lbs+
Over 80,000 lbs: no flags, signs, lights or escorts required for weight alone. Devices may still be triggered by size.
On multi-lane roads
Escorts begin at 12'1" wide
Width
Permit required8'7" – 12'
Over 8'6" up to 12'0": permit, flags and Oversize Load signs required. No lights or escorts.
Rear escort or amber light12'1" – 14'6"
Over 12'0" to 14'6": rear escort, or amber/strobe lights on the power unit and rear extremity in lieu of the escort. An amber warning light may replace the rear escort. Source: Iowa Admin. Code 761-511.20(2) chart and footnote (ARC 9512C).
Rear escort or amber light14'7" – 16'6"
Over 14'6" to 16'6": rear escort, or amber/strobe lights on the power unit and rear extremity in lieu of the escort. An amber warning light may replace the rear escort. Source: Iowa Admin. Code 761-511.20(2) chart and footnote (ARC 9512C).
Rear escort16'7" – 18'
Over 16'6" to 18'0": rear escort required. No lights-in-lieu option at this width.
Rear escort18'1"+
Over 18'0" is beyond the published chart. Escorts are set by the permit-issuing authority, which may require additional escorts. Above 20 ft, this row's escorts are the minimum; the permit sets any more.
Height
Permit required13'7" – 14'6"
Over 13'6" to 14'6": permit, flags and Oversize Load signs required. No escort.
Front + High pole14'7"+
Over 14'6" to 20'0": front escort with a mounted height pole. The escort measures all vertical clearances. Above 20 ft, this row's escorts are the minimum; the permit sets any more.
Length
Permit required75'1" – 85'
75'1" to 85'0" overall: flags and Oversize Load signs required. No lights or escorts.
Permit required85'1" – 120'
Over 85' to 120' overall: flags, signs and amber warning lights required. No escort.
Rear escort120'1"+
Over 120' overall: rear escort required. Above 200 ft, this row's escorts are the minimum; the permit sets any more.
Weight
Permit required80,001 lbs+
Over 80,000 lbs: no flags, signs, lights or escorts required for weight alone. Devices may still be triggered by size.
When a permitted load can move
- Standard hours
One-half hour before sunrise to one-half hour after sunset. Movement only when roads are clear of ice and snow and visibility is at least one-quarter mile. The permit-issuing authority may authorize another period if the move is better accomplished then.
- Night travel
Allowed between one-half hour after sunset and one-half hour before sunrise if width is 12' or less, height 14'6" or less, length 100' or less and axle weights are legal. Roadway must be at least 22' wide with 11' lanes. Safety lighting required at the widest part of the load.
- Weekend travel
Allowed Saturday and Sunday on the same daylight schedule, or continuously if the load meets the night travel limits. No movement during a holiday weekend, which occurs when Memorial Day, Independence Day or Labor Day falls on a Friday, Saturday, Sunday or Monday.
- Holiday restrictions
No movement on Memorial Day, Independence Day or Labor Day, after 12 noon on days preceding those holidays or holiday weekends, during holiday weekends, or during special events with abnormally high traffic. Movement resumes one-half hour before sunrise the day after.
- Urban restrictions
Des Moines I-235 closed to permit loads 7-9 AM and 4-6 PM. Other Des Moines highways may be added to the curfew at an officer's discretion when traffic is heavy. Confirm the current curfew days with the Iowa DOT permit office.
Signage Iowa expects
- Oversize load sign
Yellow "Oversize Load" sign at least 18" high by 7' long, 10" black letters with 1.5" stroke, mounted on the front bumper and the rear of the load. On mobile homes and factory-built structures the rear sign sits at least 7' above the road. Cover or remove when legal size.
- Flags
Red or orange fluorescent flags at least 18" square: one at each front corner of the towing unit, one at each rear corner of the load, and one at any additional protrusion in the width of the load. Rear projections over 4' also require flags.
- Beacons
Flashing or strobe amber light visible at least 500' with 360-degree warning, mounted on the towing unit, visible front and rear. Required for length over 85' to 120', front projection over 25', rear projection over 10'. May be used in lieu of an escort on some width bands.
Iowa permit office
The permit office is the authority on every number on this page. Call it, or open the official site, before you rely on a threshold for a load that is close to a line.
Already have your permit?
Decode it into a route card: authorized route, escorts, curfews, weigh stations, truck stops and low-bridge alerts along the way.
3 free decodes a day · no account · no cardBefore you ask dispatch.
What are the legal limits in Iowa without an oversize or overweight permit?
In Iowa, the legal limits without an oversize or overweight permit are 8'6" wide, 13'6" high, 53'0" long (semitrailer) and 80,000 lbs gross. Legal overhang is 3'0" front and 4'0" rear. Anything over those figures needs a permit from the Iowa permit office before it moves.
When does an oversize load need an escort or pilot car in Iowa?
On 2-lane roads in Iowa, escorts begin at 12'1" wide. On multi-lane roads, escorts begin at 12'1" wide. The first escort tier is "Front escort or amber light" at 12'1" – 14'6" wide. Every tier on this page quotes its rule and source.
Can oversize loads travel at night, on weekends or on holidays in Iowa?
Night travel: Allowed between one-half hour after sunset and one-half hour before sunrise if width is 12' or less, height 14'6" or less, length 100' or less and axle weights are legal. Roadway must be at least 22' wide with 11' lanes. Safety lighting required at the widest part of the load. Weekend travel: Allowed Saturday and Sunday on the same daylight schedule, or continuously if the load meets the night travel limits. No movement during a holiday weekend, which occurs when Memorial Day, Independence Day or Labor Day falls on a Friday, Saturday, Sunday or Monday. Holidays: No movement on Memorial Day, Independence Day or Labor Day, after 12 noon on days preceding those holidays or holiday weekends, during holiday weekends, or during special events with abnormally high traffic. Movement resumes one-half hour before sunrise the day after.