Trucking Regulations in Washington
Complete guide to weight limits, speed limits, permits, chain laws, and special rules for commercial truck drivers operating in Washington.
Max Gross Weight
105,500 lbs on state routes with permit
Truck Speed Limit
60 mph on some urban interstates
Diesel Tax
$0.494 per gallon diesel + federal (among highest in US)
Weight & Size Limits in Washington
| Measurement | Limit |
|---|---|
| Max Gross Vehicle Weight | 105,500 lbs on state routes with permit |
| Max Axle Weight | 20,000 lbs single axle, 34,000 lbs tandem |
| Max Trailer Length | 75 ft for doubles on designated routes |
| Max Width | 102 inches |
| Max Height | 14 ft |
Speed Limits for Trucks in Washington
Rural Interstate
70 mph
Urban Interstate
60 mph
Truck-Specific
60 mph on some urban interstates
Fuel Tax & Tolls in Washington
Diesel Fuel Tax
$0.494 per gallon diesel + federal (among highest in US)
Toll Roads & Bridges
SR-520 Bridge (Seattle), I-405 Express Lanes, SR-167 HOT Lanes, Tacoma Narrows Bridge. Good to Go! transponder. Truck tolls $4-12 depending on facility.
Chain Laws & Weather Requirements
Chain carry required November 1 to April 1. WSDOT issues chain-up requirements on Snoqualmie Pass (I-90), Stevens Pass (US-2), and other mountain passes.
Oversize & Overweight Permits
WSDOT Motor Carrier Services. Cascade Range crossings have strict dimensional restrictions. Permits available online.
Port of Entry & Weigh Stations
Weigh stations on I-5, I-90, I-82. Washington State Patrol commercial vehicle enforcement. International border crossing at Blaine (I-5).
Special Rules for Washington
Hazmat Route Restrictions
Hazmat restricted through downtown Seattle and on SR-520 floating bridge. Designated routes around port areas. Cascade Range pass closures may trap hazmat loads on either side.
Rest Area & Parking Rules
Rest areas allow 8-hour parking. Good rest area coverage on I-90 and I-5. Anti-idling law: no idling over 5 minutes in most areas.
DOT Inspection Frequency
Moderate to high. Washington State Patrol commercial vehicle division focuses on I-5, I-90, and mountain pass corridors.
Looking for Trucking Jobs in Washington?
Browse CDL driver positions and connect with carriers operating in Washington.
Frequently Asked Questions About Washington Trucking Regulations
What is the maximum truck weight in Washington?
Washington allows up to 105,500 lbs on designated state routes with proper permits and multi-axle configurations. Interstate highways follow the federal 80,000 lbs limit. This supports the state's logging, agriculture, and construction industries.
Are chains required in Washington?
Washington requires trucks to carry chains from November 1 through April 1. WSDOT issues chain-up requirements on Snoqualmie Pass (I-90), Stevens Pass (US-2), White Pass (US-12), and other mountain routes. Chain-up areas are well-marked and staffed during storm events.
How expensive is diesel fuel in Washington?
Washington has one of the highest diesel taxes in the US at $0.494 per gallon at the state level, plus federal tax. Combined with generally high Pacific Northwest fuel prices, Washington is one of the most expensive states for refueling.
What are the Cascade Range pass closures?
Snoqualmie Pass (I-90) and Stevens Pass (US-2) are the primary east-west crossings of the Cascades. Both passes close frequently during winter storms, sometimes for 12-24+ hours. Chains are required even with all-wheel drive on commercial vehicles. Drivers should check WSDOT pass reports before departing.
How congested is Seattle for trucks?
Seattle area I-5 and I-405 are among the most congested corridors in the western US. Truck traffic to/from the Ports of Seattle and Tacoma adds to congestion on I-5 south of downtown. The SR-99 tunnel through downtown restricts vehicles over 14 ft. Plan 1-3 extra hours for Seattle metro transit.