The short answer
Wyoming trucks that never leave the state: the USDOT number with WY after it when it is 26,001 lbs or more, seats 16 or more or carries placard-level hazmat.
Wyoming intrastate trucks at 26,001 lbs and up (GVWR/GCWR/GVW/GCW) show 'USDOT <number> WY' plus the carrier name, both sides, readable from 50 feet. For-hire carriers at or under 26,000 lbs generally do not need a USDOT number in Wyoming (taxis carrying more than 7 passengers excepted); private carriers at 26,000 lbs or less are exempt from the Wyoming Commercial Vehicle Act.
Trucks that cross a state line, or haul freight that starts or ends in another state, follow the federal rule instead: the USDOT number and your legal name when it is 10,001 lbs or more, carries placard-level hazmat, seats 9 or more for hire or seats 16 or more (49 CFR 390.21T(b)(2)).
Rules verified against the primary sources 2026-07-31, next review 2027-01-27. The full citation list is on our USDOT decals in Wyoming page and the 50-state rules table.
Eight Wyoming trucks, run through the checker
Each verdict below is what our free compliance checker returns for that truck using the verified Wyoming and federal rules. Where one changed fact flips the answer, we show the flip, because that is usually where Wyoming carriers get caught.
1. A 9,000-lb plumber's cargo van on Cheyenne service calls, Wyoming only
9,000 lbs GVWR · own tools and parts · Wyoming only
Not required
At 9,000 pounds it is under the 26,001-pound Wyoming line and it carries general freight with no placard, so no verified Wyoming or federal rule reaches it.
2. A pickup pulling an equipment trailer on landscaping jobs around Cheyenne, Wyoming only
20,000 lbs combined · own equipment · Wyoming only
Not required
At 20,000 pounds it is under the 26,001-pound Wyoming line and it carries general freight with no placard, so no verified Wyoming or federal rule reaches it.
Flip one fact: The same rig takes one job in Colorado. It is now in interstate commerce, the federal rule applies from 10,001 pounds, and it needs the USDOT number and your legal name on both sides.
3. A 26,000-lb GVWR box truck delivering furniture for pay, Cheyenne only
26,000 lbs GVWR · paid freight · Wyoming only
Not required
At 26,000 pounds it is under the 26,001-pound Wyoming line and it carries general freight with no placard, so no verified Wyoming or federal rule reaches it.
Flip one fact: At 26,001 pounds, one pound more, the same truck needs the USDOT number with WY after it.
4. A 33,000-lb tandem dump truck for a Casper contractor, Wyoming only
33,000 lbs GVWR · paid hauling · Wyoming only
USDOT number required
The Wyoming rule reaches this truck because it is 33,000 pounds, over the 26,001-pound line. The checker returns the USDOT number with WY after it, both sides. On the door that reads: USDOT 1234567 WY.
Flip one fact: Rated at 26,000 pounds, the same truck stays under the Wyoming 26,001-pound line: at 26,000 pounds no verified Wyoming rule reaches it.
5. A 15-passenger hotel shuttle van in Cheyenne, no fare charged
15 seats including the driver · passengers, not for hire · 9,500 lbs GVWR · Wyoming only
Not required
At 9,500 pounds it is under the 26,001-pound Wyoming line and 15 seats is under the 16-passenger trigger, so no verified Wyoming or federal rule reaches it.
Flip one fact: With 16 seats including the driver, the same van needs the USDOT number with WY after it.
6. A 12-passenger paid airport shuttle, Cheyenne only
12 seats · passengers for pay · 9,500 lbs GVWR · Wyoming only
Not required
At 9,500 pounds it is under the 26,001-pound Wyoming line and 12 seats is under the 16-passenger trigger, so no verified Wyoming or federal rule reaches it.
Flip one fact: The same shuttle takes one job in Colorado. It is now in interstate commerce, the federal rule applies from 10,001 pounds, and it needs the USDOT number and your legal name on both sides.
7. A 14,000-lb placarded propane bobtail, Wyoming only
14,000 lbs GVWR · placard-level hazmat · Wyoming only
USDOT number required
The Wyoming rule reaches this truck because it carries placard-level hazmat. The checker returns the USDOT number with WY after it, both sides. On the door that reads: USDOT 1234567 WY.
Flip one fact: Haul non-placarded freight in the same truck and the hazmat trigger drops away: at 14,000 pounds no verified Wyoming rule reaches it.
8. A hotshot pickup and gooseneck running Cheyenne to Denver loads
26,000 lbs combined · paid freight · interstate
USDOT number required
Because it crosses state lines, the federal marking rule applies: it is 26,000 pounds, over the 10,001-pound line. The checker returns the USDOT number and your legal name, both sides. On the door that reads: USDOT 1234567 · Your Company LLC. Because it hauls for hire across state lines, the checker also lists the MC number as commonly displayed but not required.
Flip one fact: Keep the same rig inside Wyoming and the federal rule drops away: at 26,000 pounds no verified Wyoming rule reaches it.
The checker weighs rating, registered and actual weight, operation, for-hire status, cargo, passenger count and farm status. It does not model axle count or vehicle type, so if your truck is unusual, confirm with WYDOT — Motor Vehicle Services / Compliance & Investigation.
What goes on the door in Wyoming
- One marking, both sides of the power unit: USDOT 1234567 WY, which is the USDOT number with WY after it.
- No inch minimum in Wyoming. The legal standard is a color that contrasts with the truck and letters readable from 50 feet in daylight. We cut 2-inch letters, which clears that bar on any door.
- The WY after the number. Wyoming's rule is written for trucks that stay in Wyoming, and it reads USDOT 1234567 WY. The federal rule for trucks that cross state lines has no suffix, so a truck that does both is usually cut to the federal format; ask us if yours does.
Across the Wyoming line
The Wyoming line only matters while the truck stays home. One job in Colorado, or one load that starts or ends out of state, makes it interstate commerce, and the federal 10,001-pound rule applies no matter where either state draws its own line. For a truck that works near the border it helps to know how the neighbors differ for their own in-state trucks:
- Colorado: no verified in-state USDOT rule in our checker (its own rule is about your company name and the CO PUC number).
- Idaho: 26,001 pounds.
- Montana: 26,001 pounds.
- Nebraska: the federal 10,001 pounds even in-state.
- South Dakota: 26,001 pounds.
- Utah: 26,001 pounds.
Neighbor lines come from the same verified rule files the checker uses; each state's page has its citations.
Who enforces it in Wyoming
Door markings in Wyoming are the business of WYDOT — Motor Vehicle Services / Compliance & Investigation. Questions about your registration or number: (307) 777-4375, agency site. The federal side, USDOT numbers and the MCS-150, is the FMCSA Wyoming Division: (307) 772-2305, MCWYOFF@dot.gov. A marking violation is written at the roadside and follows the carrier on the inspection report, which is why it is worth getting the two lines right the first time.
For the marking mistakes inspectors catch most often, see USDOT marking mistakes that fail roadside inspections.
Where the Wyoming rule comes from
- WYDOT Rules & Regs, Motor Carriers Ch. 1 Appendix, § 390.21(b)(3) as modified — 'USDOT 123456 WY' format for intrastate numbers
- WYDOT Rules & Regs, Motor Carriers Ch. 1 Appendix, § 390.5 — intrastate CMV = 26,001+ lbs GVWR/GCWR/GVW/GCW
- WYDOT Rules & Regs, Motor Carriers Ch. 1, § 10(c) — private carriers at 26,000 lbs or less exempt
- 49 CFR 390.21T — the federal marking rule for interstate carriers
Read in full and verified 2026-07-31; next scheduled review 2027-01-27.
Wyoming USDOT number FAQ
Does a landscaper's pickup and equipment trailer at 20,000 lbs need a USDOT number in Wyoming?
Not under the verified Wyoming rule. At 20,000 pounds it is under the 26,001-pound Wyoming line and it carries general freight with no placard, so no verified Wyoming or federal rule reaches it. The same rig takes one job in Colorado. It is now in interstate commerce, the federal rule applies from 10,001 pounds, and it needs the USDOT number and your legal name on both sides.
Does a 26,000-lb box truck hauling for pay need a USDOT number in Wyoming?
Not under the verified Wyoming rule. At 26,000 pounds it is under the 26,001-pound Wyoming line and it carries general freight with no placard, so no verified Wyoming or federal rule reaches it. At 26,001 pounds, one pound more, the same truck needs the USDOT number with WY after it.
Does a 15-passenger van that charges no fare need a USDOT number in Wyoming?
Not under the verified Wyoming rule. At 9,500 pounds it is under the 26,001-pound Wyoming line and 15 seats is under the 16-passenger trigger, so no verified Wyoming or federal rule reaches it. With 16 seats including the driver, the same van needs the USDOT number with WY after it.
Does a 12-passenger paid shuttle need a USDOT number in Wyoming?
Not under the verified Wyoming rule. At 9,500 pounds it is under the 26,001-pound Wyoming line and 12 seats is under the 16-passenger trigger, so no verified Wyoming or federal rule reaches it. The same shuttle takes one job in Colorado. It is now in interstate commerce, the federal rule applies from 10,001 pounds, and it needs the USDOT number and your legal name on both sides.
What exactly goes on the door in Wyoming?
One marking, both sides of the power unit: USDOT 1234567 WY, which is the USDOT number with WY after it. No inch minimum in Wyoming. The legal standard is a color that contrasts with the truck and letters readable from 50 feet in daylight. We cut 2-inch letters, which clears that bar on any door.
Get the Wyoming markings cut to spec
USDOT Number Decals
Your USDOT number cut to the 50-foot standard — set of 2, both sides.
$16+Full Compliance Kit
Legal name + USDOT + MC + GVW, all cut to match.
$54.95+Wyoming USDOT Number Decal Set of 2 with WY Suffix
Cut to the Wyoming rule above.
from $18.95USDOT Decals in Wyoming
Every Wyoming truck decal we cut, with the Wyoming rule on one page.
from $16Not sure which truck above is yours? Run the free Wyoming check, seven questions, sources cited. Rules for other states are in our intrastate USDOT guide and the 50-state rules table.
General information, not legal advice. Fleet Decal Depot is a decal maker, not a government agency. Rules change; confirm with WYDOT — Motor Vehicle Services / Compliance & Investigation and FMCSA before you operate.