Iowa transportation regulations

The legal weight, dimension and axle limits for commercial vehicles in Iowa, and where the state permit office is.

Your route

Iowa is highlighted. Select the other states on your route to compare their limits.

Legal dimensions

MeasureLegal maximum
Width8' 6"
Height13' 6"
Length, semi-trailer53'
Length, single vehicle41'
Length, overall53'
Front overhang3'
Rear overhang4'

Legal weights

MeasureLegal maximum
Gross vehicle weight80,000 lbs
Gross weight, single vehicle
Single axle20,000 lbs
Tandem axle34,000 lbs
Tridem axle60,000 lbs
Single axle, non-divisible
Tandem axle, non-divisible
Tridem axle, non-divisible

Last checked September 2026. States revise legal limits, and a limit can depend on the road, the axle spacing or the configuration in ways one table cannot capture. Iowa is the authority — use this to plan, and confirm anything you are close to.

Iowa permit offices

Oversize/ Overweight/ Temporary Trip/ Fuel

Oversize / Overweight

Phone
(515) 239-1101
Email
oversizepermits@iowadot.us
Weekdays
8:30 AM – 4:30 PM