Washington Highway Use Permits: Rules and Process

Dec. 3, 2025, 5:18 p.m.
Washington’s Highway Use Permits are required for commercial carriers moving vehicles or loads that exceed the standard legal size, weight, or configuration allowed on state highways. These permits ensure safe transport, protect public infrastructure, and keep carriers compliant with WSDOT regulations.
Washington Highway Use Permits

What Is a Washington Highway Use Permit?

A Washington Highway Use Permit—often issued through the WSDOT Commercial Vehicle Services (CVS) office—authorizes trucks that exceed legal limits to operate on designated state routes. Carriers must obtain the proper permit before entering or traveling through Washington.

These permits apply to movements such as:

  • Oversize or overweight loads

  • Specialized equipment

  • Construction machinery

  • Industrial components

  • Superloads requiring route analysis

When a Highway Use Permit Is Required

You must obtain a permit if your vehicle or load exceeds any of the following Washington legal limits:

Legal Size Limits

  • Width: 8 ft 6 in

  • Height: 14 ft

  • Length:

    • Single vehicle: 40 ft

    • Combination: Up to 75 ft (varies by configuration)

  • Overhang: Front 3 ft / Rear 15 ft

Legal Weight Limits

  • Single axle: 20,000 lbs

  • Tandem axle: 34,000 lbs

  • Gross weight: Varies by axle count and spacing (WSDOT formula applies)

If the load cannot be reduced to legal size or weight, a highway use permit is required.

Types of Washington Highway Use Permits

Washington offers several permit categories depending on the movement:

1. Single-Trip Permit

Authorizes one specific trip for an oversize or overweight load.

2. Annual Permit

Allows repeated movements within specified size limits. Common options:

  • 14-ft height annual permit

  • 12-ft wide annual permit

  • 105,500-lb overweight annual permit (with restrictions)

3. Special Transportation Permit

Used for unusual or complex configurations.

4. Superload Permit

Required when loads exceed:

  • 16 ft wide

  • 16 ft high

  • 125 ft long

  • 200,000+ lbs GVW

These require engineering review and custom routing.

How to Apply for a Washington Highway Use Permit

Carriers can apply through https://www.washingtontruckingonline.com/, by phone - (206) 339-6683

For overdimension loads applications are being submitted over he phone only (206) 339-6683

Steps:

  1. Gather load details

    • Dimensions

    • Weight by axle group

    • Vehicle configuration

    • Origin & destination

  2. Check route restrictions

    • Bridge limits

    • Construction zones

    • Weather restrictions

    • Curfews (especially in metro areas)

  3. Submit application  

  4. Pay applicable permit fees
    Fees vary depending on trip type, weight, and dimensions.

  5. Receive permit to your email address & follow all conditions
    Conditions may include:

    • Escort requirements

    • Travel time limits

    • Specific approved routes

    • Safety equipment (flags, signs, lights)

Key Rules Carriers Must Follow

To remain compliant:

Travel Time Restrictions

  • Most oversize loads cannot travel during darkness, unless the permit specifically allows it.

  • Weekend and holiday restrictions may apply.

Escort Requirements

Pilot cars may be required based on:

  • Width (10+ ft)

  • Height (14+ ft, depending on route)

  • Length (125+ ft)

Safety Equipment

Loads may require:

  • Oversize Load signs

  • Red or amber lights

  • Safety flags

  • Conspicuity markings

Weather Restrictions

Travel may be suspended during:

  • High winds

  • Ice

  • Heavy snow

  • Severe visibility conditions

Permit Violations and Penalties

WSDOT can issue fines for:

  • Traveling without a permit

  • Exceeding permit limits

  • Violating route instructions

  • Operating during restricted hours

  • Missing required escorts

Fines can be substantial—especially for overweight violations, which increase per pound over the limit.

Tips for Carriers

  • Always check WSDOT Commercial Vehicle Restrictions before departure.

  • Bookmark the Washington Bridge & Roadway Guideline Maps.

  • Use a certified routing service for complex loads.

  • Keep permits accessible for roadside inspection.