Washington Oversized Load Transportation Guide
Important: We are not a permit service and we do not arrange permits for carriers. All information provided below is for information purposes only. Always read permits and provisions carefully as we cannot guarantee the accuracy of information provided below.
Navigating wide load regulations in Washington requires careful planning to ensure heavy load compliance. Whether you’re transporting large equipment or managing logistics for heavy haul, here’s what you need to know about permit requirements, restrictions, and safety regulations for transporting oversized loads.
Permit Requirements for Oversized Loads
- Single-trip permits are valid for three days and must be secured before entering Washington.
- No permit purchases at Ports of Entry (POEs)—apply in advance.
- Superloads (exceeding 200,000 lbs or extreme dimensions) require extended processing.
Operating Hours & Travel Restrictions for Oversized Vehicles
- Standard travel window: 30 minutes before sunrise to 30 minutes after sunset (including weekends).
- Night travel allowed for loads under 12’ wide, 14’6” high, and 105’ long (must comply with Federal lighting standards under 49 CFR 393.11).
- Commuter curfews apply in metro areas (Seattle, Tacoma, Olympia, etc.)—check permit attachments for details.
- City route validation required for Seattle/Tacoma transit.
Legal dimensions for heavy haul trucks
- Length: 53’ semi-trailer (standard), 56’ trailer permit available for legal loads
- Overhang: 3’ front, 15’ rear (from last axle center)
- Width: 8’6” (standard)
- Height: 14’ (permits don’t guarantee clearance)
- Weight Limits: 80,000 lbs gross (default). Divisible loads exceeding 80,000 lbs may not need a permit if axle weights comply
Routine Permit Requirements
- Length: 125’ (trailer + load)
- Width: 16’ (14’ on 2-lane roads)
- Height: 16’
- Weight: Up to 130,000 lbs (7 axles)
Escort Requirements for Oversized Load Safety
- Multiple-Lane Highways:
- Length > 125’ → 1 escort
- Width > 14’ → 1 escort (case-by-case if >16’)
- Height > 14’6” → 1 pole escort
- 2-Lane Highways:
- Length > 105’ → 1 escort
- Width > 11’ → 2 escorts (case-by-case if >16’)
Safety regulations for transporting oversized loads
- Signs & Flags:
- “Oversize Load” signs required (front & rear, 5’–7’ high)
- Flags on all corners and overhangs
- Lighting for Night Moves:
- Amber lights on protruding sides
- Red lamp on rearmost edge
- Lift Axles: Must be grounded if exceeding legal weights
Key Takeaways for Logistics for Heavy Haul
- Route planning for overweight vehicles—avoid curfew zones
- Verify height clearances (permits don’t guarantee them)
- Use specialized transport services for superloads
- Follow escort requirements to avoid fines