USDOT Number Decals: What Contractors Need on the Truck

Which Contractors Need a USDOT Number?

Many contractors with work trucks need a USDOT number, especially those who cross state lines with a commercial vehicle over the federal weight thresholds, or carry certain materials. Some states also require a USDOT number for trucks used only inside the state.

The rules depend on vehicle weight, what you carry and where you drive, so the FMCSA's registration pages are the place to confirm whether your trucks need one. If they do, the marking on the truck must match your registration.

Roofers, plumbers, landscapers, HVAC contractors and builders with heavier trucks or trailers should all check. A pickup used for estimates may not need it; a loaded flatbed hauling materials across a state line may.

What Size Should USDOT Decals Be?

Size the decals so the lettering reads from 50 feet in daylight, which is the FMCSA readability standard. The product page opens on a pair of 6 x 24 inch decals, a size that fits a typical truck door with the name and number on two lines.

Two 6" × 24" 3M IJ-180Cv3 USDOT Number Decals are $64.19, which is about $32.10 a decal. Artwork prep is $14.99 per item. Printed in the USA in 48 hours and shipped nationwide, flat $10 shipping to any US address.

Letter height and contrast matter more than the overall size. Bold, simple letters in a contrasting color read from much farther than thin or decorative ones. Choose a plain, heavy font, and keep the line spacing generous.

Where Should USDOT Decals Go on the Truck?

Put the decals on both sides of the power unit, the truck or tractor itself, not the trailer. On most trucks that means the driver and passenger doors, below the window and above any door logo, where they are easy to see and read.

Keep them clear of door handles, trim, body lines and rivets, which break up the lettering and make the decal harder to apply. A flat, clean panel of the door is the best spot.

If you replace a truck, the decals do not move with it. Order a new pair for each power unit. Before you sell or retire a truck, remove your marking, so your USDOT number does not stay on a vehicle you no longer operate.

What Color Should a USDOT Decal Be?

Choose a color that contrasts sharply with the truck: white or a light color on a dark door, black or a dark color on a white or light door. The rule calls for a sharp contrast, and the proof is checked for it before anything prints.

Avoid color pairs that look fine up close but blur from a distance, such as red on dark blue or gray on silver. If your truck is a mid tone color, use a contrasting background panel behind the lettering.

Why Is Cast Vinyl Used for Truck Decals?

USDOT decals are printed on 3M IJ-180Cv3, a cast vinyl. Cast vinyl is thin and conforms to the slight curves of a truck door without pulling back, which is why it is the standard film for vehicle graphics. The gloss laminate protects the print from washing, weather and road grime.

Calendared vinyl, which suits flat windows and signs, is more likely to lift on a curved door. For more on films, see adhesive vinyl types.

How Do You Apply USDOT Decals to a Truck Door?

Apply the decals to a clean, dry door at a comfortable temperature, out of hot direct sun. Wash the door, wipe it with isopropyl alcohol, and let it dry.

Position each decal with painter's tape, measure from the bottom of the window or a body line so both sides sit at the same height, and tape a hinge across the middle. Peel the backing from one half, squeegee from the hinge out, then do the other half. Lift the transfer tape slowly, folded back flat.

Decals ship on the full vinyl sheet with the cut lines plotted. Remove the extra vinyl around the letters first, and use transfer tape, which is not included, to move the lettering as one piece.

How Do You Mark a Fleet of Trucks?

Mark every power unit the same way, with the same name, number, font, size and position. A fleet that matches looks organized to customers and is easier to check for compliance: one glance down the row shows every truck is marked.

Order a pair of decals for each truck, plus a spare pair or two. A spare lets you replace a damaged decal the same day, or mark a new truck while the next order prints.

Keep one master file with the exact wording and layout. When you add a truck next year, the reorder matches the trucks already on the road. If your company name or USDOT details change, update the file first, then reorder for every truck at once.

What Other Lettering Belongs on a Work Truck?

Beyond the required marking, most of the truck door is free advertising. A work truck parks in driveways, job sites and lots all day, and every person who walks past can read it.

Add the business name or logo, the main service and a phone number or web address, in that order of size. Keep the USDOT marking separate and clear, usually below the logo, so it stays easy to read and is never mistaken for decoration.

For the logo, car door decals on the same cast vinyl match the USDOT lettering. For a rear window, perforated film keeps the driver's view. For a full or partial wrap in San Antonio, see vehicle wraps.

Should the USDOT Decal Match Your Door Logo?

It can, and it looks more professional when it does. Use the same font and color family as your door logo, so the truck reads as one design. Car door decals on the same cast vinyl carry your logo and phone number, with the USDOT marking below.

Two 18" × 18" 3M IJ-180Cv3 Car Door Decals are $148.39, which is about $74.20 a decal. Artwork prep is $14.99 per item. Printed in the USA in 48 hours and shipped nationwide, flat $10 shipping to any US address.

For a removable option on the logo, vehicle magnets come off when the truck is used for something else. Keep the required USDOT marking on a permanent decal so it cannot fall off.

What Should You Check on USDOT Decal Proofs?

Check first for a typo in the USDOT number. One wrong digit makes the marking wrong. Check the number on the proof against your registration, digit by digit.

Next, check for a name that does not match the registration, such as a nickname instead of the legal name or registered trade name.

Also check for low contrast: a stylish dark gray on a black truck that looks fine in a photo and blurs at 50 feet.

How Do You Order USDOT Number Decals?

Type your carrier name and USDOT number, choose the size and the vinyl, and place the order. A free proof comes with every order, with the contrast checked before anything prints. Artwork prep is $14.99 per item if you send a phone photo or a ChatGPT image of a design.

Decals print in 48 hours after proof approval and ship for a flat $10 to any US address. In San Antonio, Inline also installs vehicle graphics; elsewhere, the decals are made to apply yourself.