Motor Carriers

Oversize/overweight permits

Determine if a permit is required

  • A permit is issued to a carrier to allow operation of a vehicle or load that exceeds the statutory limits.
  • Permitted loads must be nondivisible.
  • Permits are issued by the Iowa DOT for state and interstate highways only. Separate permits must be obtained from local city or county jurisdictions for travel on those roadways.

Definition of an indivisible load

Any load or vehicle exceeding applicable length, height, width or weight limits that if separated into smaller loads or vehicles, would:

  1. Compromise the intended use of the vehicle (i.e., make it unable to perform the function for which it was intended).
  2. Destroy the value of the load or vehicle (i.e., make it unusable for its intended purpose).
  3. Require more than eight work hours to dismantle using appropriate equipment.

Legal dimensions

A permit is typically required if vehicle dimensions exceed:

  Width       8 feet 6 inches
  Height    13 feet 6 inches
  Length     45-foot single vehicle
      53-foot trailer, loaded or empty
      57-foot lowboy trailers used exclusively for the transportation of construction equipment

More information and exceptions to the dimensions listed above is available at the following links.


A permit is typically required if vehicle gross weight exceeds 80,000 pounds. Maximum individual axle weight allowed under permit is 20,000 pounds per axle.

For more information and exceptions to the above weight limits:

Additional resources and information is available at the following links.

If you have questions:

Phone: 515-237-3264
Fax: 515-237-3257


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