The following information about Iowa Oversize Permits is for informational purposes only. It’s important to always read your permits and provisions sheets carefully as we cannot guarantee the accuracy of the information provided. If you have any questions or need assistance, you can contact the following number.

Iowa DOT#: 256-234-4265

Iowa Oversize Permits Duration

In Iowa Oversize Permits are valid for a duration of five days. It is mandatory to obtain the permit before entering the state.

Operating Time

Vehicles with permits, up to 100 feet in length, 11 feet in width, and 14 feet 6 inches in height, along with permitted axle limits, are eligible for continuous travel seven days a week (24/7), as long as they traverse roadways with a minimum width of 22 feet and minimum lane width of 11 feet. Additionally, the travel must include safety lighting as specified on Iowa’s provisions sheet. Larger loads have the flexibility to travel from half an hour before sunrise to half an hour after sunset, including Saturdays and Sundays.

Restricted Travel in Iowa

Travel on Des Moines I-235 is restricted from 7:00 am to 9:00 am and from 4:00 pm to 6:00 pm, Monday through Friday. Other highways in Des Moines may be included in the curfew at the officer’s discretion if traffic conditions are dense. Please check for any travel restrictions during holidays or holiday weekends.

Legal Dimensions for Iowa Oversize Permits

Length:

A 53-foot semi-trailer and load are considered legal. However, any overhang that causes the semi-trailer and load length to exceed 53 feet is not permissible without a permit. Steel pipe, beams, and construction materials do not qualify for an exemption.

Width:

8′-6″

Height:

13′-6″

Weight:

80,000 Gross

  • Single – 20,000
  • Tandem – 34,000
  • Tridem – 42,000 (w/ minimum 8′-1″ axle spacing)

Routine Permit Limits in Iowa

Length:

120′

Width:

18′

Height:

18′

Weight:

  • Single – 20,000
  • Tandem – 46,000
  • Tridem – 60,000
  • Quad – 80,000

Steer Tire:

The permit does not specify the weight limit for the steer axle, but enforcement bases it on the rating of a single steer tire (as indicated on the tire’s side), multiplied by two. For Iowa Oversize Permits, your licensing must cover the weight for which you intend to obtain a permit.

Loads exceeding these dimensions or weight are considered as super loads.

Call (832) 454-5883 For Permit Consultation

Iowa Oversize Permits image

Escort Requirements for Iowa  Oversize Load Permits

On all highways:

Length:

  • Over 85′ – one escort or amber revolving light
  • Over 120′ – one escort

Overhang:

If the front projection exceeds 25 feet or the rear overhang is over 10 feet, a single escort is required. Alternatively, an amber revolving light or strobe light on the rear of the load is acceptable for rear overhangs exceeding 10 feet.

Height:

Over 14′-6″ – one escort with high pole.

On 4-lane roadways:

Width:

  • 14′-6″ to 16′-6″ – one rear escort or two amber revolving or strobe lights (one on power unit, one on rear extremity of vehicle or load)
  • Over 16′-6″ on 4-lane roadways – one escort.

On 2-lane highways:

Width:

If the width surpasses one-half of the roadway width, up to and including 14 feet 6 inches, one front escort is required. For widths exceeding 14 feet 6 inches, one escort is necessary. However, if the width is up to and including 14 feet 6 inches, exceeds one-half of the roadway width, and the lane width is 12 feet or more with adequate shoulders, an amber or strobe light on the power unit and on the rear extremity of the vehicle or load may be used instead of an escort.

Miscellaneous

Blades, buckets, counterweights, and similar components do not need to be removed when the load is slightly over dimension. However, if the load is overweight, these components must be transported separately.

Signs, Flags & Lights for Iowa Oversize Load Permits

When a vehicle and load exceed 75 feet in length, 8 feet 6 inches in width, and/or 14 feet 4 inches in height, it is mandatory to display “Oversize Load” signs and flags. Flags are also necessary for rear overhang exceeding 4 feet on all permitted vehicles/loads. These flags should be mounted at each front corner of the towing unit, at each rear corner of the load, and at any wide points or protrusions of the load.

In cases where the length exceeds 85 feet, the front overhang exceeds 25 feet, or the rear overhang exceeds 10 feet (with the light positioned on the load in the rear), or the weight exceeds 80,000 lbs, an amber revolving light at least 7 inches high and 7 inches in diameter is required on the towing unit. An escort can be used instead of the amber light.