Motor carrier classes by state
Washington does not charge a flat price for weight. It charges a rate per mile, read off a band of pounds over legal capacity, so the same load costs a different amount depending on how far it travels. Almost everything else an aggregate hauler deals with here — tonnage, tarps, lift axles, licensed weight — is built on that same habit of pricing the thing that is actually variable.
What makes an aggregate fleet hard to price is largely portable: trips measured in minutes rather than hours, most of the working day spent off a paved surface, hoists and bodies that a physical damage schedule seldom valued correctly, and a loss history built out of low-speed events at pits and placement sites. Those belong to the class, and the dump trucking insurance page is where they are worked through.
What Washington adds is a set of design decisions that change the paperwork a fleet generates and, with it, what an underwriter can actually verify. Overweight capacity is bought by the mile. Additional tonnage is bought by the day and cannot be bought for part of one. The cover question arrives as a width permit rather than as a load-securement rule. The lift axle is regulated by where its control is mounted. And the licensed weight on the registration is set by a statutory floor rather than by preference.
Each of those produces a document. A per-mile permit names a route. A tonnage permit names a start date and a count of days. A tarping system permit names a width. A registration names a declared gross weight that the statute forces to be at least one and a half times the empty truck. Those four documents, read against each other and against an equipment schedule, describe a Washington aggregate operation more accurately than any narrative on an application.
Every figure below is cited to the statute or rule that sets it, with the amendment or filing the source itself displays. Washington publishes its code and its rules on the same open host, and the sections were read there directly rather than from a summary.
Running aggregate on Washington permits? Send the permit type alongside the declared gross weight on each registration — in this state those two numbers are set by different statutes and they do not automatically agree.
RCW 46.44.0941, captioned “Special permits—Fees” and last amended by 2023 c 281 s 1, sets the overweight charge as a cost per mile rather than a flat fee. The schedule reads off excess weight over legal capacity as provided in RCW 46.44.041, and the rate rises with the band: $.07 per mile at 0 to 9,999 pounds over, $.21 at 15,000 to 19,999, $.49 at 30,000 to 34,999, $1.14 at 50,000 to 54,999, $2.82 at 80,000 to 84,999, and $4.25 at 100,000 pounds. Past that point the statute stops using a table and states the rule instead: the fee is “$4.25 plus 50 cents for each 5,000 pound increment or portion thereof exceeding 100,000 pounds.”
The consequence for an aggregate operation is that route length becomes a price input, not just a scheduling input. Two permits at identical weight cost different amounts because one haul is longer, and a contract that moves the pit or the placement site changes the permit cost without changing the load. An operator bidding site work in Washington is bidding a distance as much as a tonnage.
The same section sets flat fees for the movements that are overlegal without being overweight — $10.00 for a single trip, $20.00 for thirty days where the only overlegal feature is width or height, $10.00 for thirty days where it is length only. Fixed load vehicles get their own lines: $70.00 for up to thirty days for a three-axle fixed load vehicle under 65,000 pounds gross, and $90.00 for up to thirty days for a four-axle fixed load vehicle meeting RCW 46.44.091(1) and weighing less than 86,000 pounds gross.
Three provisos travel with every one of those numbers, and the statute states them in one breath rather than in a note: “(a) The minimum fee for any overweight permit shall be $14.00, (b) the fee for issuance of a duplicate permit shall be $14.00, (c) when computing overweight fees prescribed in this section or in RCW 46.44.095 that result in an amount less than even dollars the fee shall be carried to the next full dollar if 50 cents or over and shall be reduced to the next full dollar if 49 cents or under.” The $14.00 floor is what keeps very short permitted moves from costing almost nothing, and it is the number a small local haul actually pays.
Issuing authority is split by who maintains the road. RCW 46.44.090, last amended by 2006 c 334 s 17, lets the department of transportation permit on state highways under its own rules and lets a local authority permit on a public highway under its jurisdiction “and for the maintenance of which such authority is responsible.” A haul that crosses from a state route onto a county road crosses a permitting boundary at the same moment.
Separate from the permit track, Washington sells short-term capacity against an already-licensed truck. RCW 46.44.095, captioned “Temporary additional tonnage permits—Fees” and last amended by 1993 c 102 s 5, opens the door once a combination has been licensed to 80,000 pounds or a three-or-more-axle single unit has been licensed to 40,000 pounds. The permit “is valid for periods of not less than five days at two dollars and eighty cents per day for each two thousand pounds or fraction thereof,” and the statute adds four words that decide how it is bought: “The fee may not be prorated.”
That is a pricing rule with an operational edge. A three-day surge of heavy work still buys five days. A fraction of two thousand pounds still buys a full two thousand. An operator who needs a modest amount of extra capacity for a short window pays for a block, and the block is the unit the state sells.
WAC 468-38-030, filed under WSR 05-04-053 effective 2/28/05, scopes the program in ways that matter to a dump fleet. Eligibility runs to three-or-more-axle single unit trucks, three-or-more-axle truck-tractors including those with a legal dromedary area, and a two-axle truck-tractor pulling double trailers. Tonnage may be purchased up to the legal capacity of the vehicle, “not to exceed one hundred five thousand five hundred pounds,” based on axle count, axle spacing and the number and size of tires. And the rule answers a question operators ask constantly: the permits “are only issued to power units,” never to the trailer.
There is also a hard ceiling on using licensing trip permits as a substitute for licensed tonnage. Because the additional tonnage permit is sold for a minimum of five days, the rule requires “a minimum of two three-day trip permits” where trip permits stand in for licensed weight, and then caps the whole arrangement: “Only three trip permits can be issued to a vehicle within a thirty-day period, allowing for a maximum of nine days of additional tonnage in any thirty-day period.” A seasonal plan built on repeated short bursts of extra weight runs into that ceiling before it runs into the fee.
The permit also cannot outlive its licensing. The additional tonnage permit may not extend beyond the valid license period, which ties the whole arrangement back to the registration rather than to the calendar.
Washington runs an oversize permit class whose subject is the covering system itself. WAC 468-38-071, captioned “Maximums and other criteria for special permits—Divisible” and last filed under WSR 19-24-067 effective 12/28/19, provides at subsection (2)(f) for “An overwidth permit, termed a tarping system permit,” issued to a vehicle or combination carrying a divisible load when the unit is equipped with a tarping system as defined in WAC 468-38-073 (5)(n).
The threshold and the condition are stated together: “A tarping system permit is required for any divisible load exceeding one hundred and two inches (eight feet six inches) in width but not exceeding nine feet in width, all of which must be within the confines of the tarping system dimensions. For example, bulging of the tarping material, to accommodate the load, is not authorized.” The permit is the authority to display the special conditions, it can be run alongside either of the overlength permits in the same subsection, and a unit operating under it is exempt from the requirements and restrictions of WAC 468-38-075(1).
Read that against the width allowance for hardware. Subsection (3) excludes non-load-carrying devices from measurement but then draws a line: “Safety and efficiency appurtenances, such as, but not limited to, tarp rails and splash suppression devices, may not extend more than three inches beyond the width of a vehicle.” So the rails are width-exclusive within three inches, the tarp itself may reach nine feet under permit, and a bulge is outside both.
The load-covering duty sits in the traffic code rather than the permit rule. RCW 46.61.655, captioned “Dropping load, other materials—Covering” and last amended by 2005 c 431 s 1, requires at subsection (2) that the load, and any covering that subsection (3) calls for, be securely fastened so that neither works loose. Subsection (3) then attaches the covering duty to a named commodity set — a paved-highway load of dirt, sand or gravel susceptible to escaping — and supplies an alternative measured inside the bed rather than over the top of it, so the duty can be discharged by how the body is filled. Subsection (1) carries a narrow carve-out — “except that sand may be dropped for the purpose of securing traction.”
The enforcement tail is what makes this an underwriting question rather than a housekeeping one. Subsection (7) grades failure to secure a load: a gross misdemeanor in the first degree where criminal negligence causes substantial bodily harm to another, a misdemeanor in the second degree where it causes damage to property of another, and an infraction where it does not reach either. Subsection (4)(b) adds a duty most fleets do not have in writing: a vehicle carrying deposits of mud, rocks or other debris on its body, fenders, frame, undercarriage, wheels or tires must be cleaned before it operates on a paved public highway. A tracked-out shoulder is a statutory violation in Washington, and it is the kind of allegation that arrives attached to a general liability claim rather than an auto one.
Adding a lift axle or a tarping system to a Washington unit? Both change what the truck is permitted to do here, and both are cheaper to check before the equipment schedule is bound than after a roadside inspection.
RCW 46.44.042, captioned “Maximum gross weights—Axle and tire factors” and last amended by 2006 c 334 s 15, adds a tire-based constraint on top of the wheelbase table. The base rule caps gross weight “upon any tire concentrated upon the surface of the highway in excess of six hundred pounds per inch width of such tire.” Then it states the equipment rule twice, deliberately, so that the second statement has no date attached to it:
The two-tire alternative is available but it costs capacity: “Instead of the four or more tires per axle requirements of this section, an axle may be equipped with two tires limited to five hundred pounds per inch width of tire.” The section does not apply to vehicles operating under oversize or overweight permits while carrying a nonreducible load, which is a carve-out an aggregate hauler almost never reaches, because aggregate is reducible.
Four categories are allowed to run at the full 600 pounds per inch: a nonliftable steering axle or axles on the power unit; a tiller axle on firefighting apparatus; a rear booster trailing axle equipped with two tires on a ready-mix concrete transit truck; and a straddle trailer manufactured before January 1, 1996 in fruit bin service, with a 515-pound-per-inch figure on sixteen and one-half inch tires for later straddle trailers meeting the same use criteria. The ready-mix booster line is the one that surprises mixed construction fleets, because it names a specific truck type and does not extend to the dump body beside it in the yard.
Width is measured off the manufacturer rather than off a tape: for pneumatic tires the width is “the maximum overall normal inflated width as stipulated by the manufacturer when inflated to the pressure specified and without load thereon.” That makes the tire sidewall marking part of the compliance record, and it is worth having on the equipment schedule when a fleet converts to a different tire size.
The section closes with a delegated power that carries its own condition, and the condition is the load-bearing part: “The department of transportation, by rule with respect to state highways, and a local authority, with respect to a public highway under its jurisdiction, may extend the weight table in RCW 46.44.041 to one hundred fifteen thousand pounds. However, the extension must be in compliance with federal law, and vehicles operating under the extension must be in full compliance with the 1997 axle and tire requirements under this section.” The table it extends is the one in RCW 46.44.041, last amended by 2016 c 24 s 1, which runs on the stated formula W = 500((LN/N-1)+12N+36), tops out at 105,500 pounds, and supplies its own reading convention for wheelbase measurements: “When inches are involved: Under six inches take lower, six inches or over take higher.”
WAC 468-38-280, captioned “Retractable axles” and last filed under WSR 06-07-025 effective 4/7/06, is an equipment specification rather than a weight rule. It asks what a retractable axle must satisfy in order to carry the weight provided in RCW 46.44.041, and gives three cumulative criteria: a manufacturer’s rating of at least eight thousand pounds, with weight carried not exceeding the design load capacity shown on an attached data plate or written vendor certification; weight per tire not exceeding the lesser of the manufacturer’s rating or five hundred pounds per inch of tire width, six hundred when operating under a special permit for overweight; and, in three words, “The axle must be self-steering.”
The control rule is separate and it is the part that shows up on an inspection. The rule permits the plain function and restricts the adjustment: “The simple ‘up/down’ control may be in the driver’s compartment; however, any variable control used to adjust axle loadings, by regulating air pressure or other means, must not be within reach of the driver’s compartment.” Raising and lowering is a cab function in Washington. Changing how much load the axle carries is not.
Two exceptions release the self-steering requirement, and both are bounded by the same distance. The first covers a retractable axle equipped with four tires used for weight distribution on a truck or truck-tractor that “gives the appearance of, but does not function as, a tandem axle drive configuration,” where the distance between the drive axle and the retractable axle does not exceed sixty inches. The second covers a retractable axle used adjacent to a fixed axle on a trailing unit where the distance between the two axles does not exceed sixty inches.
For a fleet, this is a specification question that gets answered at purchase and then rarely revisited. A used unit bought out of another state may carry a cab-mounted load-adjusting control that was lawful where it was built, and the axle may not be self-steering while sitting outside both sixty-inch exceptions. Neither condition announces itself in a maintenance file. Both are visible in a photograph of the dash and a tape measure taken at the frame, and both are worth settling while the physical damage schedule is still being built.
Subsection (4)(a) of WAC 468-38-071 designates a heavy haul industrial corridor on “a segment of US-97 from the Canadian border to milepost 331.12,” and the permits issued there “will authorize vehicles to haul divisible loads weighing up to the Canadian inter-provincial weight limits.” The conditions are short and each is checkable. The vehicle applying for the Canadian weight special permit “must be licensed to their maximum legal weight limit in Washington state.” The route is fixed: “Both directions of US-97 from the Canadian border at milepost 336.48 to milepost 331.12.” And verification runs on a document — “A Washington state axle spacing report is required for Canadian weight verification.”
The permitted limits are published in both systems of units, which is the clearest signal of what the corridor is for. The primary steering axle runs at 600 lbs. (272 kg) per inch (25.4 mm) of tire width with a maximum of 12,100 lbs.; other axles at 500 lbs. (227 kg) per inch; single axles at 20,000 lbs. (9,100 kg); tandem axles at 37,500 lbs. (17,000 kg). Tridem axles are read off a spread table — 46,300 lbs. at 94 to under 118 inches, 50,700 lbs. at 118 to under 141 inches, and 52,900 lbs. at 141 to under 146 inches. Gross weight is then read off a matrix by configuration and axle count that names Truck, Truck and Full Trailer, Truck and Pup, Tractor and Semi, A-Train, B-Train and C-Train, and reaches 139,994 lbs. (63,500 kg) at eight axles on a truck and full trailer and on a B-train.
The rule then supplies the tie-breaker, and it is the sentence that governs how the whole table is applied: “When computing allowable weights, the most conservative figure (whether weight per width of tire, axle weights, or gross weights) will govern.” A configuration that satisfies the gross matrix can still be limited by its tires.
The corridor permit also states, in terms, what it is not. “Displaying the US-97 heavy haul industrial corridor permit does not waive registration fees, fuel taxes, operating authority requirements, future legislative or regulatory changes. Except as provided in the provisions for the heavy weight industrial corridor on US-97, all Washington state and federal laws must be complied with.” That is a hedge the department wrote for itself, and it belongs beside any figure taken from the table.
A separate divisible-load allowance in subsection (4)(b) exists only for presidentially declared national emergencies or major disasters, is confined to loads delivering relief supplies into the declared area, and expires “no later than one hundred twenty calendar days after the date of the emergency declaration.” It is a relief measure rather than a commercial program, and a hauling contract should not be priced against it.
RCW 46.16A.455, captioned “Trucks, buses, and for hire vehicles based on gross weight,” registers commercial trucks on a declared gross weight and then constrains the declaration in both directions. Subsection (2) requires the declared gross weight to be sufficient to cover the vehicle’s empty scale weight plus the maximum load it will carry, and the empty scale weight and maximum load of any trailer it will tow — with the trailer excluded where its empty scale weight and maximum load together do not exceed four thousand pounds, or where the trailer is for personal use.
Subsection (3) supplies the floor, and it is keyed to the truck rather than to the work: “Every truck, motor truck, truck tractor, and tractor exceeding six thousand pounds empty scale weight registered under this chapter or chapter 46.87 RCW must be licensed for not less than one hundred fifty percent of its empty weight.” Two escapes follow. Where 150 percent would exceed the limits in RCW 46.44.041 or 46.44.042, the vehicle is licensed instead for the maximum weight authorized for it. And a fixed load vehicle is outside the requirement.
Increases are handled asymmetrically at two boundaries. Where the declared gross weight remains at 12,000 pounds or less, it must be increased to the end of the current registration year; for vehicles increasing to 14,000 pounds or more, it must be increased at a minimum to the expiration of the current declared gross weight license. Monthly licensing is available at 12,001 pounds and above, at one-twelfth of the annual fee for each full month plus the monthly declared gross weight license fee. The dollar amounts themselves live in RCW 46.17.355 and RCW 46.17.360, which were not opened for this page, so no Washington registration fee figure is stated here.
A declared weight is useful on a submission because it is the owner’s own written statement, filed with the state, of the maximum a unit is licensed to carry. It can be set against the axle and tire configuration under RCW 46.44.042 and against the tonnage permits the fleet actually buys. Where a unit sits near its 150 percent floor and still runs loaded aggregate every day, those documents are describing two different trucks, and the gap is cheaper to close before it reaches trucking auto liability pricing.
RCW 46.44.080, captioned “Local regulations—State highway regulations” and last amended by 2006 c 334 s 16, grants and then limits local authority in a single chain of provisos. Local authorities may prohibit motor trucks or impose weight limits on highways under their jurisdiction “whenever any such public highway by reason of rain, snow, climatic or other conditions, will be seriously damaged or destroyed.” Where a highway has been closed generally, they must still authorize, by general rule or special permit, school buses, emergency vehicles and “motor trucks transporting perishable commodities or commodities necessary for the health and welfare of local residents.”
Then comes the limit that decides routing disputes inside city limits: “PROVIDED FURTHER, That the governing authorities of incorporated cities and towns shall not prohibit the use of any city street designated a part of the route of any primary state highway through any such incorporated city or town by vehicles or any class of vehicles or impose any restrictions or reductions in permissible weights unless such restriction, limitation, or prohibition, or reduction in permissible weights be first approved in writing by the department of transportation.” A city street that carries a primary state highway route is not the city’s to downweight alone.
Every local restriction also has a second condition precedent. The authority must act by ordinance or resolution and must erect and maintain signs at both ends of the affected stretch, and the statute makes the ordinance ineffective until that has been done. An unposted restriction is not yet in force, which makes the sign rather than the minute book the operative document for a driver.
The department holds the same power over state highways and must give public notice of a closure or restriction. When it exercises that power for a freeze-thaw event, the restriction takes a published shape rather than a percentage. WAC 468-38-080, captioned “Emergency load restrictions for heavy vehicles,” sets out two sign-posted tables — “emergency load restrictions” and “severe emergency load restrictions” — each giving a permitted gross load for each tire size in two columns, conventional tires and tubeless or special with a .5 marking. Under the ordinary table, an 11.00 conventional tire carries 4,500 lbs. and a 10-22.5 carries 3,400 lbs.; under the severe table the same 11.00 and over column falls to 3,000 lbs. and a 10-22.5 to 2,250 lbs. Only vehicles equipped with tires in the table may operate under permit while either sign is posted.
Three answers in the same rule bear directly on dump configurations: there is no allowance for a rigid trail axle, no allowance for more than two tires on the steering axle, and a front-axle carve-out permitting a maximum ten thousand pound front-axle load for a truck or truck-tractor on conventional 10:00 x 20 or 11:00 x 22.5 tires or larger. A temporary additional tonnage permit does not override any of it. The department attaches its own operational note to the rule, and it is worth carrying as written: “The department recommends that carriers check the department’s website www.wsdot.wa.gov/freight/mcs for possible advance warning on road restrictions.”
What a violation costs is set separately. RCW 46.44.105 assesses a basic penalty of not less than fifty, seventy-five and one hundred dollars on a first, second and third finding, then adds a per-pound schedule on top: three cents per pound for the first four thousand pounds over; $120 plus twelve cents per additional pound from 4,001 through 10,000; $840 plus sixteen cents from 10,001 through 15,000; $1,640 plus twenty cents from 15,001 through 20,000; and $2,640 plus thirty cents per additional pound at 20,001 and more. Violating a posted limitation carries its own penalty of not less than one hundred fifty dollars, and on a second violation within twelve months involving the same power unit the court suspends the certificate of license registration for not less than thirty days. The court may suspend the penalty for five hundred pounds of excess weight per axle on a first violation in a calendar year, capped at a two thousand pound suspension, and the statute states plainly that outside that first violation the basic and additional penalties may not be suspended.
The state minimum is a licensing threshold. The program an operator actually needs is built from these lines:
We write dump and aggregate hauling as a named class rather than as an exception to general trucking, and we read each account against the weight and permit regime of the state it operates in. For a Washington operator that means starting from what the trucks are actually licensed and configured to carry, sizing physical damage to bodies and hoists rather than to a chassis value, and treating pit, stockpile and job-site work as its own exposure rather than an extension of the highway auto form.
If the operation also runs freight under separate authority, the Washington trucking insurance page covers the state’s broader motor carrier picture, and the dump trucking insurance page covers the class mechanics that apply wherever the operator runs.
By distance. RCW 46.44.0941 sets a cost per mile that rises with the band of excess weight over legal capacity, from $.07 per mile at 0 to 9,999 pounds over to $4.25 per mile at 100,000 pounds, and above that adds 50 cents for each 5,000 pound increment or portion thereof. Three provisos travel with the schedule: a $14.00 minimum for any overweight permit, $14.00 for a duplicate, and rounding to the next full dollar at 50 cents or over. The section was last amended by 2023 c 281 s 1.
No. RCW 46.44.095 sells the temporary additional tonnage permit for periods of not less than five days, at two dollars and eighty cents per day for each two thousand pounds or fraction thereof, and states that the fee may not be prorated. Where licensing trip permits stand in for licensed tonnage, WAC 468-38-030 requires a minimum of two three-day trip permits and allows only three trip permits to a vehicle in a thirty-day period, so a maximum of nine days of additional tonnage is available in any thirty days.
Yes, and the permit is named for the tarp rather than the load. WAC 468-38-071(2)(f) creates an overwidth permit termed a tarping system permit, required for any divisible load exceeding 102 inches in width but not exceeding nine feet, all of which must sit within the confines of the tarping system dimensions. The rule gives its own example of what fails: bulging of the tarping material to accommodate the load is not authorized. Tarp rails themselves may not extend more than three inches beyond the width of the vehicle.
RCW 46.61.655(3) requires a paved-highway load of dirt, sand or gravel susceptible to escaping to be covered so as to prevent spillage, and provides an alternative measured inside the bed rather than over the load. Subsection (2) requires the load and any required covering to be securely fastened. Subsection (4)(b) separately requires a vehicle carrying deposits of mud, rocks or other debris on its body, fenders, frame, undercarriage, wheels or tires to be cleaned before operating on a paved public highway.
Because the second statement removes the date. RCW 46.44.042 first requires an axle manufactured after July 31, 1993 carrying more than ten thousand pounds gross weight to be equipped with four or more tires, then states separately that an axle carrying more than ten thousand pounds gross weight must have four or more tires regardless of date of manufacture. An older axle is not grandfathered. The alternative is two tires limited to five hundred pounds per inch width of tire, which reduces what the axle may carry.
WAC 468-38-280 allows a simple up and down control in the driver’s compartment but requires that any variable control used to adjust axle loadings, by regulating air pressure or other means, must not be within reach of the driver’s compartment. The same rule requires the retractable axle to be self-steering, subject to two exceptions that each depend on a spacing of no more than sixty inches, and requires a manufacturer’s rating of at least eight thousand pounds.
WAC 468-38-071(4)(a) permits divisible loads at Canadian inter-provincial weight limits on both directions of US-97 from the Canadian border at milepost 336.48 to milepost 331.12. The vehicle must be licensed to its maximum legal Washington weight and a Washington state axle spacing report is required for Canadian weight verification. Limits are published in pounds and kilograms, and where the tire, axle and gross figures disagree, the rule directs that the most conservative figure governs.
RCW 46.16A.455(3) requires every truck, motor truck, truck tractor and tractor exceeding six thousand pounds empty scale weight to be licensed for not less than one hundred fifty percent of its empty weight, unless that would exceed the limits in RCW 46.44.041 or 46.44.042, in which case the vehicle is licensed for the maximum authorized, or unless it is a fixed load vehicle. The declared gross weight must also cover the empty scale weight plus the maximum load, and any towed trailer over four thousand pounds.
Every figure on this page was read at the source below on August 11, 2026, with the effective date of the version read. Treat each as current as of that date rather than as permanent.
Send the declared or registered weights alongside the axle configurations, and tell us where the material moves from. We will size the program against the work the trucks actually do rather than against a statutory floor.
