The short answer
Maryland trucks that never leave the state: the USDOT number with MD after it when it is 10,001 lbs or more or seats 11 or more for hire (except farm vehicles).
Maryland-only carriers over 10,000 lbs display a Maryland-issued number in the federal marking style with an MD suffix — the state's own example reads 'Rotz Trucking USDOT 12345 MD'. Farm trucks are exempt from the display.
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 2026-07-28, next review 2027-01-24. The full citation list is on our USDOT decals in Maryland page and the 50-state rules table.
Nine Maryland trucks, run through the checker
Each verdict below is what our free compliance checker returns for that truck using the verified Maryland and federal rules. Where one changed fact flips the answer, we show the flip, because that is usually where Maryland carriers get caught.
1. A 9,000-lb plumber's cargo van on Baltimore service calls, Maryland only
9,000 lbs GVWR · own tools and parts · Maryland only
Not required
At 9,000 pounds it is under the 10,001-pound Maryland line and it carries general freight with no placard, so no verified Maryland or federal rule reaches it.
2. A 14,000-lb GVWR service truck on landscaping jobs around Baltimore, Maryland only
14,000 lbs GVWR · own equipment · Maryland only
USDOT number required
The Maryland rule reaches this truck because it is 14,000 pounds, over the 10,001-pound line. The checker returns the USDOT number with MD after it, both sides. On the door that reads: USDOT 1234567 MD.
3. A 10,000-lb GVWR cutaway box van delivering furniture for pay, Baltimore only
10,000 lbs GVWR · paid freight · Maryland only
Not required
At 10,000 pounds it is under the 10,001-pound Maryland line and it carries general freight with no placard, so no verified Maryland or federal rule reaches it.
Flip one fact: At 10,001 pounds, one pound more, the same truck needs the USDOT number with MD after it.
4. A 33,000-lb tandem dump truck for a Frederick contractor, Maryland only
33,000 lbs GVWR · paid hauling · Maryland only
USDOT number required
The Maryland rule reaches this truck because it is 33,000 pounds, over the 10,001-pound line. The checker returns the USDOT number with MD after it, both sides. On the door that reads: USDOT 1234567 MD.
Flip one fact: Rated at 10,000 pounds, the same truck stays under the Maryland 10,001-pound line: at 10,000 pounds no verified Maryland rule reaches it.
5. A 40,000-lb grain truck on farm plates, Maryland only
40,000 lbs GVWR · farm vehicle · Maryland only
Not required
At 40,000 pounds it is under the 10,001-pound Maryland line, the Maryland farm exemption takes it out even at this weight and it carries general freight with no placard, so no verified Maryland or federal rule reaches it.
Flip one fact: Take it off the farm exemption, by plating or by use, and it is marked like any other truck at this weight: the USDOT number with MD after it.
6. A 15-passenger hotel shuttle van in Baltimore, no fare charged
15 seats including the driver · passengers, not for hire · 9,500 lbs GVWR · Maryland only
Not required
At 9,500 pounds it is under the 10,001-pound Maryland line and 15 seats is under the 11-passenger trigger, so no verified Maryland or federal rule reaches it.
Flip one fact: Haul the same loads for pay and the Maryland rule reaches it: the USDOT number with MD after it.
7. A 12-passenger paid airport shuttle, Baltimore only
12 seats · passengers for pay · 9,500 lbs GVWR · Maryland only
USDOT number required
The Maryland rule reaches this truck because it seats 12, meeting the 11-passenger trigger and hauls for hire. The checker returns the USDOT number with MD after it, both sides. On the door that reads: USDOT 1234567 MD.
Flip one fact: Haul only your own goods in the same truck and at 9,500 pounds no verified Maryland rule reaches it.
8. A 14,000-lb placarded propane bobtail, Maryland only
14,000 lbs GVWR · placard-level hazmat · Maryland only
USDOT number required
The Maryland rule reaches this truck because it is 14,000 pounds, over the 10,001-pound line. The checker returns the USDOT number with MD after it, both sides. On the door that reads: USDOT 1234567 MD.
9. A hotshot pickup and gooseneck running Baltimore to Harrisburg 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.
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 MDOT SHA — Motor Carrier Division.
What goes on the door in Maryland
- One marking, both sides of the power unit: USDOT 1234567 MD, which is the USDOT number with MD after it.
- No inch minimum in Maryland. 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 MD after the number. Maryland's rule is written for trucks that stay in Maryland, and it reads USDOT 1234567 MD. 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 Maryland line
The Maryland line only matters while the truck stays home. One job in Pennsylvania, 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:
- Delaware: 26,001 pounds.
- Pennsylvania: 17,001 pounds.
- Virginia: the federal 10,001 pounds even in-state.
- West Virginia: any weight for hire and 10,001 pounds for trucks hauling their own goods.
Neighbor lines come from the same verified rule files the checker uses; each state's page has its citations.
Who enforces it in Maryland
Door markings in Maryland are the business of MDOT SHA — Motor Carrier Division. Questions about your registration or number: (410) 582-5734, agency site. The federal side, USDOT numbers and the MCS-150, is the FMCSA Maryland Division: (443) 703-2360, FMCSA-MDOFFICE@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 Maryland rule comes from
- MDOT SHA 'Maryland Intrastate DOT Numbers' brochure — 'Legislation enacted in Maryland during 2001 requires that every truck over 10,000 pounds capacity, truck tractor, and bus operated on public roads, unless…
- 49 CFR 390.21T — the federal marking rule for interstate carriers
Read in full and verified 2026-07-28; next scheduled review 2027-01-24.
Maryland USDOT number FAQ
Does a 10,000-lb box truck hauling for pay need a USDOT number in Maryland?
Not under the verified Maryland rule. At 10,000 pounds it is under the 10,001-pound Maryland line and it carries general freight with no placard, so no verified Maryland or federal rule reaches it. At 10,001 pounds, one pound more, the same truck needs the USDOT number with MD after it.
Does a 40,000-lb farm truck need a USDOT number in Maryland?
Not under the verified Maryland rule. At 40,000 pounds it is under the 10,001-pound Maryland line, the Maryland farm exemption takes it out even at this weight and it carries general freight with no placard, so no verified Maryland or federal rule reaches it. Take it off the farm exemption, by plating or by use, and it is marked like any other truck at this weight: the USDOT number with MD after it.
Does a 15-passenger van that charges no fare need a USDOT number in Maryland?
Not under the verified Maryland rule. At 9,500 pounds it is under the 10,001-pound Maryland line and 15 seats is under the 11-passenger trigger, so no verified Maryland or federal rule reaches it. Haul the same loads for pay and the Maryland rule reaches it: the USDOT number with MD after it.
Does a 33,000-lb dump truck need a USDOT number in Maryland?
Yes. The Maryland rule reaches this truck because it is 33,000 pounds, over the 10,001-pound line. The checker returns the USDOT number with MD after it, both sides. On the door that reads: USDOT 1234567 MD. Rated at 10,000 pounds, the same truck stays under the Maryland 10,001-pound line: at 10,000 pounds no verified Maryland rule reaches it.
What exactly goes on the door in Maryland?
One marking, both sides of the power unit: USDOT 1234567 MD, which is the USDOT number with MD after it. No inch minimum in Maryland. 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 Maryland 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+Maryland USDOT Number Decal Set of 2 with MD Suffix
Cut to the Maryland rule above.
from $18.95USDOT Decals in Maryland
Every Maryland truck decal we cut, with the Maryland rule on one page.
from $16Not sure which truck above is yours? Run the free Maryland 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 MDOT SHA — Motor Carrier Division and FMCSA before you operate.