Missouri Oversize Load Permits, Regulations & Axle Rules

Standard oversize permits in Missouri allow movement from one-half hour before sunrise to one-half hour after sunset. That window applies whether you're on an interstate, a four-lane divided state road, or a two-lane county route; the road class doesn't change when the clock starts.

The overweight-only exception is meaningful. A load that is overweight but stays at legal height, no wider than 12'6", and no longer than 110 feet may move continuously day and night, outside of holidays and the tourist-area rules below. Loads up to 12'6" wide (legal height, and no more than 110 feet long) can also run at night under a single trip or blanket permit. Hay up to 14' wide may travel after dark as long as height, length, and weight are all legal. And for short urban moves, major equipment or special loads can operate 1:00 AM through 6:00 AM Monday through Friday, or Sunday 1:00 AM through noon, with permit authorization.

Six holidays shut down oversize travel entirely: New Year's Day, Memorial Day, Independence Day, Labor Day, Thanksgiving, and Christmas. The blackout doesn't simply cover the calendar day. Restrictions start at noon on the last business day before the holiday and run through one-half hour before sunrise on the first business day after it returns. A three-day holiday can easily consume five calendar days.

Weekends are not a universal ban. Loads up to and including 16' wide may travel on Saturdays and Sundays. Loads wider than 16', and all loads in designated tourist zones, cannot move on weekends. Two tourist corridors impose Saturday and Sunday blackouts regardless of width: Branson from May 1 through November 30, and Lake of the Ozarks from May 25 through Labor Day.

Missouri's major metro areas add weekday rush-hour curfews for oversize loads (not overweight-only). The St. Louis area (including St. Louis City and County and adjacent I-70, I-64, and Route 94 segments in St. Charles and Jefferson Counties) blocks movement from 6:30 to 9:00 AM and 3:30 to 6:30 PM, Monday through Friday. Kansas City's core zone uses 7:00 to 9:00 AM and 4:00 to 6:00 PM. Springfield city limits run 7:00 to 9:00 AM and 4:00 to 6:00 PM, with I-44 and US 60 carrying a 4:00 to 6:00 PM restriction and US 65 running 7:00 to 9:00 AM and 3:30 to 6:00 PM. Superloads on non-divided highways face an additional restriction of no movement from 6:30 to 9:00 AM and 3:30 to 6:00 PM; on divided highways superloads run the standard sunrise-to-sunset window. When the Missouri State Highway Patrol is escorting a superload, the Patrol determines movement dates and times.

Weather stops any permitted move: no travel when roads are snow- or ice-covered, when crosswinds are hazardous to the load's movement, or when visibility drops below 500 feet. Missouri sets no 24-hour continuous movement allowance for oversize loads.

Hay and farm products. Loads of hay are not required to comply with the reducible-load rule for width. Single-trip permits allow hay up to 14' wide, and those moves may run at night as long as height, length, and weight are all legal. Annual blanket permits cover hay up to 12'6" wide. Self-propelled hay-hauling equipment is fully exempt from length restrictions.

Farm implements and construction equipment. Farm equipment with dual tires and construction equipment carrying an attached blade or bucket are not required to meet the reducible-load requirement for width. Annual blanket permits cover farm implements and construction equipment up to 12'6" wide and/or 150' overall. A separate 100-mile-radius blanket permit is available for farmers and farm implement dealers; it allows widths up to 14'6" with all other dimensions and weight legal. Farm machinery being delivered or moved for repairs by an implement dealer is exempt from length restrictions on all state highways except the interstate. Agricultural implements operating occasionally over short distances at daylight are also length-exempt.

Auto and boat transporters. Standard (non-stinger-steered) units may run up to 75' overall, exclusive of up to 3' of front overhang and up to 4' of rear overhang; those overhangs are additional, not counted in the 75'. Stinger-steered transporters run up to 80', exclusive of up to 4' front and 6' rear. Public utility poles and pipe may travel under a blanket permit up to 150' overall.

Livestock, grain, and milk. Loads of livestock, grain, and grain co-products carry a higher legal weight limit, up to 85,500 lbs, on Missouri highways other than the interstate. Raw fluid milk is held to the same 85,500 lb limit on non-interstate routes and requires a special overweight permit for 80,001 to 85,500 lbs on interstate highways.

Cranes, well drill rigs, and concrete pump trucks. Annual blanket overweight permits are available for cranes with four or fewer axles, well drill rigs, and concrete pump trucks, subject to the same dimensional caps as other equipment of their type.

Emergency response vehicles. Tourist area, curfew, night travel, and holiday restrictions are all waived for the initial response to an emergency site.

Missouri does not carve out any commodity-specific routing seasons beyond the tourist-area weekend rules and the farm-implement exemptions noted above.

Missouri calls this tier a Super Heavy and Large Load in its administrative code, though "Superload" is the term used throughout MoDOT's FAQs and public guidance. A load becomes a superload when it exceeds any one of four routine permit limits: more than 16 feet wide, more than 16 feet high, more than 150 feet in overall length, or more than 160,000 pounds gross vehicle weight.

The process begins with an online application through MoDOT's Motor Carrier Services (MCS). Once submitted, applicants should allow at least two weeks for a route evaluation. If any problem on the state highway system would prevent the load from reaching its destination, the application will not be approved; the feasibility review happens before a permit is issued, not after. A minimum of $425 must be placed in escrow to cover bridge analysis before MCS will begin processing the application.

MoDOT's engineers conduct a structural analysis and feasibility study covering every bridge and roadway the load would traverse. The fee for that analysis varies by distance: $425 for routes up to 50 miles, $625 for 51 to 200 miles, and $925 for routes over 200 miles. An identical permit with an identical vehicle configuration can reuse the same bridge study if it is less than 60 days old (or less than 30 days old for loads over 300,000 lbs), avoiding a duplicate fee. Complex moves may also require a traffic control plan or sketches.

A superload carrying a loaded height above 17' must provide written approval from the relevant utility company before the permit can issue, confirming that aerial lines can be disturbed along the route. If a move is heavy enough to require adjustments to signal or sign mast arms, flashers, or any other MoDOT-owned structure, the applicant must hire a MoDOT-approved contractor to perform that work. Before-and-after studies of the highways and bridges on the route will be conducted, and any resulting damage is repaired at the permittee's expense.

Loads exceeding 350,000 lbs gross require an additional power unit to accompany the load; it is treated as part of the vehicle configuration for bridge analysis purposes, though MCS may waive this requirement for short moves. The maximum single-axle weight for any superload move is generally 22,400 lbs. Insurance must be at least $2,000,000 combined single limit, with cargo insured under a separate policy. An oversize surcharge of $250, labeled a movement feasibility fee, applies to every superload permit triggered by width, height, or length (it stacks onto the base permit fee). The movement feasibility fee reflects the required engineering review that distinguishes this tier from a routine oversize permit.

Superloads may travel on Saturdays and Sundays if width is 16' or less (outside tourist areas and holidays). For all other dimensions, the MSHP determines movement dates and times in coordination with the permit.

Missouri's route review obligations are calibrated to what makes a load demanding, not set at one uniform threshold.

For superloads (any load exceeding 16' wide, 16' high, 150' long, or 160,000 lbs gross), MoDOT performs the route evaluation internally. The turnaround is approximately two weeks. Engineers review every structure along the proposed corridor; the bridge and roadway analysis must be completed and the escrow satisfied before MCS approves the permit. The entire review is a precondition of the permit, not a post-issuance check.

For overlength loads exceeding 150' overall, Missouri requires that the permittee or an authorized representative either physically drive the proposed route in advance of the permit issuing or use a roadway geometric modeling software application approved by MoDOT, and attest in writing that all turns, curves, and clearances can be safely negotiated. This obligation offers carriers a practical alternative to a full in-person drive for complex routes.

For overweight loads above 160,000 lbs gross, a bridge and roadway analysis fee is required at application, and MoDOT's structural review covers every bridge on the route before the permit is issued.

For overheight loads in general, Missouri places the responsibility on the permittee to check all structures and overhead wires along the route for clearances before movement begins. A height detection vehicle must physically lead any load over 15'6" tall. Loads exceeding 17' in height require written utility company approval for any aerial lines that will be disturbed; that document must be submitted with the application. Physically lifting, stressing, or manipulating any overhead obstruction on the travelway is prohibited; if a signal mast arm or sign structure needs adjustment, the carrier must hire a qualified, MoDOT-approved contractor to perform and supervise that work.

Missouri does not require permits for on-site clearance of overhead utilities by the carrier where no permit-specific route survey is required, but the burden of confirming clearances before movement falls entirely on the permittee.

The escorting law enforcement agency in Missouri is the Missouri State Highway Patrol (MSHP). Patrol escorts are required, not discretionary, when a load crosses any of four codified thresholds: more than 16' wide on any two-lane highway; more than 18' wide on a divided or multi-lane undivided highway; more than 150' in overall length on any highway; or more than 17' in height on any highway. The Patrol may also require an escort at any time it deems necessary due to the complexity of the route or the load. Separately, the general escort framework (outside the superload tier) triggers a law enforcement escort at over 200' overall length on all highways.

The carrier does not contact the Patrol directly off a table and book an appointment. Superload law enforcement escorts are arranged through and in coordination with MCS as part of the permitting process; MCS may waive the Patrol escort requirement for a given move, or authorize local or military law enforcement to substitute. MoDOT is running a pilot program to streamline superload law enforcement escort requirements; carriers should confirm current Patrol coordination procedures when applying.

MSHP may conduct a Level I vehicle inspection before providing escort services. The carrier is responsible for reimbursing the Missouri State Highway Patrol, and any local or military law enforcement acting as escort, for their services. Failure to reimburse may result in revocation of all future permitting authority, not just the permit at issue.

Below the Patrol thresholds, civilian escort vehicles handle the full range of oversize dimensions, and the count climbs by road type (divided, multi-lane undivided, or two-lane) and dimension.

By width: 12'6" to 14' takes one rear escort on divided and multi-lane undivided roads, one front on two-lane. 14' to 16' takes one rear on divided highways, front and rear on undivided multi-lane and two-lane. 16' to 18' takes front and rear on all road types, plus an additional front on two-lane. Over 18', front and rear plus one MSHP unit on all road types, with an additional front on two-lane.

By height: over 15'6", a front height detection vehicle with a vertical clearance detection device, in continuous two-way communication with the power unit, on all highways; it satisfies the front escort requirement except where multiple fronts are prescribed. Over 17', that detection vehicle plus MSHP on all highways, with an additional front on two-lane.

By length: 110' to 125', one rear escort on all roads except divided highways. 125' to 150', one rear on all highways. 150' to 200', one rear on all highways, plus an additional front on two-lane and undivided. Over 200', one rear plus MSHP on all highways, with an additional front on two-lane. By weight: over 350,000 lbs gross, front and rear civilian escorts on all highways, with an additional front on two-lane.

No more than two front and two rear civilian escorts are required for any single load except movements of unusual complexity. Escorts travel about 300' ahead of or behind the load, adjusted to traffic in cities and towns.