Oversize & Overweight Permits

Anyone hauling a load or driving a vehicle in excess of the legal weight or size limitations is required to have a permit before moving on Island County roads.

A Washington state permit is required for oversize and overweight loads on state roads and highways.

In general, the maximum legal dimensions are:

  • Width: 8 ½ feet
  • Height: 14 feet
  • Length: 
    • Single Truck: 40 feet
    • Truck and Trailer: 75 feet
    • Trailer: 53 feet.
  • Weight:
    • Single axle: 20,000 lbs
    • Tandem axle: 34,000 lbs
    • Tire size: 500 lbs maximum per inch width

See RCW  46.44.041 for the Washington State Vehicle Table

There are also exceptions and additional requirements for oversize loads depending on the load, size of the load, total truck/trailer length and the route. See RCW 46.44 and WAC 468-38 for detailed information on load sizes.

For Island County permits, call Public Works at 360-679 7331