How to Read a Wyoming Oversize Permit: Field-by-Field Guide

In Wyoming, oversize and overweight permits come from the Wyoming Highway Patrol (WHP): port of entry staff, troopers and the Overweight Loads Office (OWL) in Cheyenne. The rules behind every permit are in the Wyoming Department of Transportation’s (WYDOT) Chapter 5, Size and Weight Limitations of Vehicles, and the Wyoming Highway Patrol commercial carrier page sums up the basics.

A few Wyoming rules catch drivers out: a permit is good for no more than four days, every permitted load must stop at the first port of entry (a PrePass green light does not let an oversize load roll past), escorted loads stay parked around six holidays, and high wind, ice and chain laws can stop a move partway. This guide walks through what a Wyoming permit holds and the published rule behind each part. WHP does not publish a sample permit, so where a detail depends on your own permit, the answer is the same: read the permit and ask the permit-issuing authority.

MI 01

Who issues Wyoming oversize permits

WYDOT Chapter 5, Section 4(a) names the authorities that may issue permits for non-divisible oversize and overweight loads, all inside the Wyoming Highway Patrol: port of entry personnel, the Overweight Loads Office (OWL) and troopers. Under WYDOT Chapter 5, Section 15(a), you get a permit on the WHP website or from any of those authorities, and you must have approval before the move starts. The WHP page links the WYDOT e-permitting site.

A non-divisible load, in Section 2(mm), is one whose parts are fixed to simulate an operating configuration, or that cannot be moved safely or without damage if taken apart. Section 15(d) says no permit is given without valid base plates or registration, a valid USDOT number, and operating authority where required. The WHP page adds that Wyoming operating authority for intrastate moves must be in place before the move (307-777-4850), and that a one-trip IRP permit ($20 per unit, $40 max) or IFTA permit ($7.50 per unit, $15 max) can be bought at the first port of entry instead.

State permits cover state highways only. WYDOT Chapter 5, Section 8(n) says the permit holder must contact city and county officials for approval to use their roads.

MI 02

The top of the permit: class, dates and fees

Start at the top. Find the permit number (shown here only as a placeholder, WY-XXXXXXXX; we never show real ones), the carrier it is issued to, the permit class and the start date. Then check:

• Permit class. WYDOT Chapter 5, Section 4 sorts Wyoming permits into classes. Class B and C permits cover separate moves within the Class B/C limits (up to 18' wide, 17' high, 120' overall and 160,000 pounds gross). Class A permits are superloads above those limits. They are approved only by the OWL, and loads over 18' wide or 18' high need at least 24 hours’ notice. Class D permits are extended-period permits for repeat moves within smaller limits (12' wide, 15' high, 75' single unit). Class E, F and W permits cover specific hauls such as hay, forest products and multi-piece loads over 117,000 pounds.
• How long it lasts. WYDOT Chapter 5, Section 7(c) says permits are issued for a reasonable period to complete the move, not more than four days. Extensions for illness, weather or mechanical trouble come from the permit-issuing authority. Permits that need escorts over a holiday weekend may run longer.
• Separate movement. Class A, B and C permits authorize separate movements. Section 2(jjj) defines that as each move to a specified location, all moves completed in the same calendar day, or a move out of the state.
• Fees. Under WYDOT Chapter 5, Section 6, an oversize permit is $25, plus 3 cents per foot (or fraction) per mile for each dimension over 15' wide, 15' high or 75' single-unit length. Overweight is 6 cents per ton (or fraction) over the legal limit per mile, with a $40 minimum. Class D is $50 for oversize. Loads over 250,000 pounds may also pay the cost of route and structure analysis and of sending staff along.
• Conditions. Section 15(e) lets the issuing authority add restrictions, require lighter loads or set alternate routes. Breaking the rules brings the penalties in W.S. 31-18-805, and the permit can be revoked (WYDOT Chapter 5, Section 13).

Carry it. Chapter 5 spells out a carry rule only for Class D permits: Section 16 says the permit and original tracking sheet must be in the specific vehicle and shown on request. Chapter 5 does not say whether a phone copy is enough for a single trip permit, so keep the permit in the cab and ask the port of entry if you plan to show it electronically.

MI 03

Vehicle, load, dimensions and weights

The load section shows overall width, height, length, single-unit length, rear overhang, axle weights, axle spacings and gross weight. Check every number against the loaded truck. Section 15(c) lists what the issuing authority may ask for: a definitive description of the load (make, model, unit and serial number), origin and destination, the full route and total miles, axle configuration with spacings and tire size, axle and gross weights, every length measurement, width and height, and plate, USDOT and authority numbers.

Legal limits. Under WYDOT Chapter 5, Section 3, legal width is 8½ feet (102 inches) and legal height is 14 feet. Length is 60' for a single unit or the semitrailer in a tractor-semitrailer, 81' for the combined trailers in a double, and 85' for other combinations. Legal axle weights are 20,000 pounds single, 36,000 tandem and 42,000 triple, with 750 pounds per inch of stamped tire width on steer tires and 600 on the others. The Wyoming Highway Patrol commercial carrier page lists legal gross as 117,000 pounds by formula on interstates, and 80,000 pounds (Table II) or 117,000 by formula on primary and secondary highways.

Permit limits. The Class B/C table in WYDOT Chapter 5, Section 4(l) caps a single axle at 25,000 pounds (29,000 when part of a tandem), a tandem at 55,000, a triple at 65,000, and gross at 160,000. A single axle on construction or off-road machinery tires may carry 55,000 pounds. Axle groups not in the table need OWL approval and may go to WYDOT’s Bridge Program. If your truck has a working lift axle (Wyoming calls it a variable load suspension axle) and dropping it reduces the overweight, the rule says you must use it.

Width on narrow roads. Section 4(b)(i) says a load over 26 feet wide is not authorized on a state highway that is mostly 32 feet wide or less, unless the OWL makes a short-distance exception.

MI 04

The route section, ports of entry and clearances

The route on the permit is the route you drive. WYDOT Chapter 5, Section 9(b) says all moves stay on the highways designated on the permit, and alternate routes need the issuing authority’s prior approval. Some moves need a full route study, and Section 15(f) warns that it can take 72 hours or more.

Ports of entry. WYDOT Chapter 5, Section 8(p) says every permitted load must stop at the first available port of entry within five miles of its route on each separate movement, and at any port along the route when a sign directs it, unless the permit shows an approved exception. The Wyoming Highway Patrol commercial carrier page adds that PrePass vehicles with a green light may keep going only if they are not hauling livestock or an oversize or overweight load.

Clearances are on you. Under Section 8(m) and 8(o), the permit holder must make sure the load can clear the route without damaging the road, overhead wires or structures, and must notify the utility if wires need lifting. The permit is not a guarantee that the load will clear any structure or bridge, and the holder must check weather and size and weight restrictions before and during the move. Some highways and bridges are posted below legal limits (Section 11). If the move damages a road or structure, Section 12 says stop, contact WYDOT or WHP, and fix the cause.

When the Department marks a bridge Reduced Speed, WYDOT Chapter 5, Section 10(d) requires a rear sign reading “CAUTION: This vehicle must slow down to 5 mph to cross bridges.” If your permit lists one, it applies.

MI 05

Escorts

Wyoming’s escort thresholds are in Chapter 5, Section 8(g) to 8(k). Each escort runs about 1,000 feet from the load unless a shorter gap is needed to control the move.

• Width, two-lane roads. One front and one rear escort when the move is 14 feet wide or more, or when any part crosses the centerline.
• Width, interstates and divided highways (and four-lane roads with a center turn lane). One rear escort at 15 feet wide or more. WHP may require more.
• Length. Front and rear on two-lane roads at 110 feet overall or when the move crosses the centerline. One rear escort on interstates and divided highways at 150 feet or more, or at the OWL’s discretion.
• Rear overhang. One rear escort on all highways at 25 feet or more, measured from the rear bumper if it meets 49 CFR 393.86, otherwise from the last tire.
• Height. A front escort with a height-measuring pole on all highways over 17 feet. Issuing authorities may require one at 17 feet or less.
• Overweight. A rear escort on all highways for any overweight move with special OWL restrictions.

A move that is mainly on the interstate does not need two-lane escorts for up to five miles of two-lane road to reach a port of entry. Moves that use both interstate and two-lane roads need one escort on the interstate and two on the two-lane sections (Section 9(m)).

Note: the Wyoming Highway Patrol commercial carrier page still says height escorts and interstate length escorts are at the approving authority’s discretion. The current Chapter 5 sets fixed triggers (over 17 feet high, 150 feet long), so follow the rule and the escort conditions printed on your permit.

Escort vehicle equipment (WYDOT Chapter 5, Section 10): a licensed single motor vehicle (no motorcycles or combinations); a revolving or strobe amber light or two 4-inch flashing amber lights visible from 1,000 feet; an OVERSIZE LOAD sign with red or fluorescent orange flags at each end; headlights and taillights on; two-way radios in the load and escort vehicles (cell and satellite phones do not count); and triangles, spare signs and flags, and a fire extinguisher (5-pound BC, or 10-pound BC for hazmat). Chapter 5 does not list an escort driver certification, so check your permit or ask WHP if you are unsure.

Convoys. Section 9(h) lets two escorted loads travel together about 1,000 feet apart on two-lane roads if neither is over 16 feet wide or 110 feet long and both are under 16 feet high (up to 18 feet wide and 130 feet on interstates). A third load must stay at least half a mile back with its own escorts.

MI 06

Travel times, holidays and weather

Wyoming’s time rules are in WYDOT Chapter 5, Section 7. Daylight hours means half an hour before sunrise to half an hour after sunset.

• Daylight only for oversize, except with WHP permission, or if the load is legal height, properly permitted, signed and lighted and is: a single unit over 60 feet long within a combination under 110 feet; a single unit alone over 60 feet but not over 75 feet; or a load up to 10 feet wide on interstates only, with a five-mile allowance on other highways for food, fuel, services or delivery.
• Overweight-only loads within legal size may move at any hour with a permit (Section 7(b)).
• Restricted hours. Issuing authorities may limit a move to daylight hours of light traffic and print those hours on the permit. Loads over 18 feet wide may not use primary and secondary highways during local school bus or heavy commuter hours, as the OWL decides.
• Holidays. Moves that need escorts may not travel on New Year’s Day, Memorial Day, Independence Day, Labor Day, Thanksgiving Day (that day only) or Christmas Day, or during local celebrations with heavy traffic. The ban runs from half an hour after sunset the evening before until half an hour before sunrise the day after. On a three-day holiday weekend it covers the whole weekend. A Saturday holiday blocks Thursday evening to Monday morning, and a Sunday holiday blocks Friday evening to Tuesday morning. In 2026, Christmas falls on a Friday, so escorted loads park from half an hour after sunset Thursday, December 24, until half an hour before sunrise Monday, December 28.
• Weekends. Chapter 5 sets no general weekend ban outside the holiday rules, but your permit may limit days or hours, and Section 7(f) says to contact WHP for emergency moves on holidays or weekends.

Weather and wind. Under Section 7(h) and 7(i), oversize and overweight loads may not move when a road is under no unnecessary travel or the chain law is in effect, and moves can be restricted on ice, drifting snow or low visibility. A load caught out may go on or turn back only to the nearest parking area or town. Mobile homes, office trailers and anything prone to blowing over must obey closures to light, high-profile vehicles. Wyoming uses four restriction classes: Class 1 (mobile homes and light oversize loads, usually when maintenance sets “9-4” wind conditions or a trooper sees high wind), Class 2 (escorted moves), Class 3 (overwidth moves) and Class 4 (all oversize moves). They do not apply to loads that are only overweight. Check the WYDOT road and travel information site (wyoroad.info) before and during the trip.

MI 07

Signs, flags and lights

Wyoming sets these marking rules in Chapter 5, Section 8(b) to 8(f):

• Sign. OVERSIZE LOAD, fully visible front and rear, yellow background, at least 60 by 10 inches, black letters at least 8 inches high and 1 inch wide on one line. Keep it clean, do not cover lights, reflectors or plates, and take it down when the vehicle is no longer oversize.
• Flags. Red or fluorescent orange, at least 12 square inches, on each front and rear corner when over legal width, on any extremity wider than the front or rear, and on rear overhang of 4 feet or more (one flag if the overhang is 2 feet wide or less, two if wider).
• Night lights for overlength loads allowed to run after daylight: a red lamp and red reflector on each corner, visible from 1,000 feet to the sides and rear.
• Night lights for overwidth loads: amber clearance lights on the front corners and red on the rear corners of whichever is wider, the load or the vehicle, plus a revolving or strobe amber light or two 4-inch flashing amber lights visible from 1,000 feet.
• Headlights and taillights on during every oversize move, a slow-moving vehicle emblem only at 25 mph or less, and outside mirrors on both sides when the load blocks the rear view.

MI 08

A pre-trip checklist, and where JaloPermit fits

Before departure on a Wyoming permit, confirm:

1. The permit is in the cab, the class fits the load, and the start date and four-day window cover the move.
2. Every dimension, overhang, axle weight, spacing and tire size on the permit matches the loaded truck, any lift axle is down if it reduces overweight, and your registration, USDOT number and authority are valid.
3. You will drive the listed route, stop at the first port of entry, and have checked clearances, posted bridges and wires. City and county roads have local approval.
4. Escorts match the permit and the thresholds, with signs, lights, flags and two-way radios.
5. The move fits the time rules: daylight unless you meet a night exception, and no escorted travel in a holiday window. The road has no chain law, no-unnecessary-travel order or wind closure that applies to your load.
6. The OVERSIZE LOAD sign, flags, lights and mirrors meet Section 8.

JaloPermit can speed up the reading part. Drop an already-issued, text-based permit PDF into the permit decoder on the JaloPermit homepage and it lays out the route, escorts, time limits, dimensions and limits on one route card, with weigh stations, truck stops and low-bridge alerts. Then compare it with the original. For the state rules at a glance, see the Wyoming page in the JaloPermit Atlas. For a general walk-through of any state’s permit, see how to read an oversize load permit. Our North Dakota, Kansas, Texas, Minnesota, Michigan, Oklahoma, Louisiana, New Mexico and Arkansas permit guides cover those states the same way, and if your trip crosses state lines, read multi-state oversize permit trips.

JaloPermit, which publishes this guide, is a reading aid for issued permit PDFs. It is not a permit-filing service and it does not plan routes or provide navigation. The issued permit always wins.

JaloPermit reads text-based PDFs only, not scans or photos. Guests get three free decodes a day with no account and no card. Logged-in users get 10 free decodes a day. After those free decodes, each one is $3.50. There is no subscription.

Questions about how JaloPermit reads a permit? Email support@jalopermit.org.

MI 09

FAQs