What Washington charges for a single-trip OS/OW permit, the limits that trigger one, and the escort thresholds — read from the state’s own publication. This rule has been in effect since 2024-07-12.
Oversize permit
$10
One price for a single-trip permit, whatever the dimensions. A 9-foot-wide load and a 16-foot-wide load pay the same.
Overweight permit
From $14
Scales with weight — there is no single figure.
A load that is both oversize and overweight pays this fee only, not both.
+ $20 Permigo service fee per permit, state fees at cost.
Legal limits
Exceed any one of these in Washington and you need a permit for this state.
Limit
Interstate
Width
8'6"
Height
14'0"
Length
125'0"
Gross weight
80,000 lbs
Single axle
20,000 lbs
Tandem axle
34,000 lbs
Trailer length
53'0"
What the permit costs
Washington prices a single-trip permit as flat rate. One price for a single-trip permit, whatever the dimensions. A 9-foot-wide load and a 16-foot-wide load pay the same.
Escort requirements
Thresholds by road class. Where two classes differ, the road you are actually on governs.
Multilane (divided)
Width
Requirement
Over 14'0"
1 rear escortExceeds 14' on multilane: one REAR pilot (row (b)). Over 12' wide + a pole-triggering height adds a rear pilot via row (i). Also: rear pilot on ALL highways when the driver 'using rearview mirrors, cannot see 200 feet to the rear' (row (j)); department discretion row (k); a flag person may substitute for the length-escort rows with permit authorization.
1 front escort + 1 rear escortExceeds 20': front + rear pilots on multilane UNDIVIDED highways (row (c)) — divided-multilane permits hard-cap at 20' wide with a median barrier (32' without). Permit width caps (RCW 46.44.092): 14' on two-lane / 20' on multilane WITH median barrier / 32' on multilane WITHOUT barrier; two-lane daylight exception to 16' wide at ≤80,000 lb.
Height
Requirement
Over 14'6"
1 front escort · height poleEXCEEDS 14'6" (exclusive — exactly 14'6" takes no pilot): one front pilot with height pole on ALL highways, pole set 3–6" above load height on the LEAD pilot (WAC 468-38-100(1)(h) + (14)). On multilane, a load that is ALSO over 12' wide adds one REAR pilot (row
1 rear escortTrailer length including load exceeds 125' → one rear pilot on multilane (row (e)) — and >125' trailing-unit(s)-plus-load is the SUPERLOAD line (jeeps/boosters count into the measure).
Over 125'0"
superload permitTrailing unit(s) plus load over 125' overall: Superload (WAC 468-38-405) — 30-day advance application + WSDOT route review.
Front overhang
Requirement
Over 3'0"
Marking requiredLegal front projection is 3' beyond the front wheels/bumper (RCW 46.44.034(1)); a 3'–7' front overhang stays inside the WAC 468-38-075 restriction-exemption envelope (NO escort at these lengths)
Rear overhang
Requirement
Over 15'0"
Marking requiredLegal rear projection is 15' beyond the center of the last axle (RCW 46.44.034(2)). Escort triggers (two-lane): combination rear overhang exceeding ⅓ of trailer-length-including-load = one rear pilot (row (d), relative — verify per load); the load tail ALSO counts into the trailer+load envelope (WAC 468-38-005).
Weight
Requirement
Over 200,000 lbs
route survey · superloadEXCEEDS 200,000 lb = superload (WAC 468-38-405, exclusive): application ≥30 calendar days ahead, WSDOT pavement/structure analysis (applicant may share analysis costs — estimates first), inadequate route = permit DENIED. Desk Guide internal tier: >300,000 lb goes to the pavement division + shipper's letter (also >16' high). Dimensional-only superloads: ≥7 days. Never self-issue. Permit axle ceilings (RCW 46.44.091): 22,000 single / 43,000 duals 3'6"–7' / 6,500 lb/ft groups 7–10'; tire cap 600 lb/in.
Two-lane
Width
Requirement
Over 11'0"
1 front escort + 1 rear escortExceeds 11' on two-lane: two pilots, one front + one rear (WAC 468-38-100(1)(a)). Permit width caps (RCW 46.44.092): 14' on two-lane / 20' on multilane WITH median barrier / 32' on multilane WITHOUT barrier; two-lane daylight exception to 16' wide at ≤80,000 lb. Pilot operators must hold WSDOT-approved certification (8-hr course, 80% test, 3-yr card; WAC 468-38-100(4)); out-of-state certs accepted from AZ/CO/GA/MN/NC/OK/UT/VA; for-hire pilot insurance $100k/$300k/$50k. Pilot vehicle: car/van or 2-axle truck ≤16,000 lb, 60–102" body, no trailer; amber 360° ≥500'; OVERSIZE LOAD sign 5'×10"; paddle/triangles/extinguisher/ANSI/hard hat/height pole/first aid.
1 front escort · height poleEXCEEDS 14'6" (exclusive — exactly 14'6" takes no pilot): one front pilot with height pole on ALL highways, pole set 3–6" above load height on the LEAD pilot (WAC 468-38-100(1)(h) + (14)). On multilane, a load that is ALSO over 12' wide adds one REAR pilot (row
1 rear escortTrailer length INCLUDING LOAD exceeds 105' → one rear pilot on two-lane highways (row (d)). Also: rear pilot on ALL highways when the driver 'using rearview mirrors, cannot see 200 feet to the rear' (row (j)); department discretion row (k); a flag person may substitute for the length-escort rows with permit authorization.
Over 125'0"
superload permitTrailing unit(s) plus load over 125' overall: Superload (WAC 468-38-405) — 30-day advance application + WSDOT route review.
Front overhang
Requirement
Over 3'0"
Marking requiredLegal front projection is 3' beyond the front wheels/bumper (RCW 46.44.034(1)); a 3'–7' front overhang stays inside the WAC 468-38-075 restriction-exemption envelope (NO escort at these lengths)
Over 20'0"
1 front escortFront overhang exceeding 20 FEET 'measured from the center of the front steer axle': one front pilot on all two-lane highways (row (f)). NOTE the datum: the rule measures from the steer-axle CENTER (≈3–4' behind the bumper) while this card keys on bumper overhang — loads within ~4' under 20' of bumper overhang should re-measure.
Rear overhang
Requirement
Over 15'0"
Marking requiredLegal rear projection is 15' beyond the center of the last axle (RCW 46.44.034(2)). Escort triggers (two-lane): combination rear overhang exceeding ⅓ of trailer-length-including-load = one rear pilot (row (d), relative — verify per load); the load tail ALSO counts into the trailer+load envelope (WAC 468-38-005).
Over 20'0"
1 rear escortRear overhang exceeding 20' (from center of rear axle) on a SINGLE-UNIT vehicle: one rear pilot on two-lane highways (row (g)); long combination tails hit the ⅓ rule at similar lengths.
Weight
Requirement
Over 200,000 lbs
route survey · superloadEXCEEDS 200,000 lb = superload (WAC 468-38-405, exclusive): application ≥30 calendar days ahead, WSDOT pavement/structure analysis (applicant may share analysis costs — estimates first), inadequate route = permit DENIED. Desk Guide internal tier: >300,000 lb goes to the pavement division + shipper's letter (also >16' high). Dimensional-only superloads: ≥7 days. Never self-issue. Permit axle ceilings (RCW 46.44.091): 22,000 single / 43,000 duals 3'6"–7' / 6,500 lb/ft groups 7–10'; tire cap 600 lb/in.
Movement restrictions
Restriction
In Washington
Night travel
Night travel allowed
Weekends
No blanket restriction
Holidays
Restricted
Movement hours
Situation
Window
Night envelope
≤12' W × ≤14'6" H × ≤105' L (incl. legal overhangs) may move at night (WAC 468-38-175(3)); beyond → 'Nighttime movement approved' must be stated on the permit; stop when visibility <500'
Overweight-only
Exempt from time restrictions if it 'can maintain posted speed limits' (WAC 468-38-075(4))
Holidays (7 days)
New Year's, Memorial, Independence, Labor, Thanksgiving + the DAY AFTER, Christmas — prohibited from NOON of the preceding day through the holiday (WAC 468-38-175(1) + Form 560-002); exemptions: ≤56' trailer incl. load / ≤68' doubles / ≤45' single / ≤7'F+≤15'R overhang / OW-at-speed / milk doubles
Weekends
NO general rule (local exception: SR 20 MP 40.82–42.75 posts no weekend moves at 12–14' wide)
Peak-hour curfews (M–F)
Seattle–Everett, Tacoma, Olympia, Vancouver, Kelso + Spokane (I-90; 11'2" width trigger) — applies to loads displaying OVERSIZE LOAD signs; overweight-only at traffic speed exempt (WSDOT curfew table / Form 560-002)
Winter / chains
Permit movement PROHIBITED where 'TRACTION ADVISORY OVERSIZE VEHICLES PROHIBITED' or chains-required signs are displayed
Speed / convoy
Permit-stated speed binding (violation voids the permit); ≤25 mph on shoulder; convoys banned for escort-required loads unless authorized
Facility caps & ferries
Facility
Rule
SR 99 tunnel (Seattle)
No loads over 15'2" high (permanent)
SR 520 floating bridge
No overwidth loads (permanent)
Tacoma Narrows (SR 16 WB)
Overwidth + >105,500 lb: use both lanes, straddle the steel-grate seam
Max 14'9" high; SB Exit 167 ≤10' wide / ≤100' long
SR 14 (MP 19–83.53)
Max 125' trailer/load; pilots required >14' wide
Columbia River crossings
Hood River Bridge + Bridge of the Gods: NO permitted loads (legal weight only) into Oregon
WSF ferries
>80,000 lb / >8'6" W / >13'4" H / <14" clearance → travel request 2 business days ahead ([email protected], (206) 390-8543); >8'6" wide = DOUBLE fare; WSF permission needed on top of the WSDOT permit; deck clearances 13'6"–16'
If you file yourself, this is the office you are dealing with. Check the linked page — some states issue OS/OW permits through their highway patrol or revenue department rather than the DOT.
RCW 46.44 (current texts, histories checked · app.leg.wa.gov · in effect since 2024-07-12. Fees and rules change; the linked document is always the authority.
Other states
Colour shows how each state prices a permit. Alaska, Hawaii and DC are not served.
