Where to Put the USDOT Number on Your Truck

Where to put USDOT number on truck: on both sides of the power unit, meaning the self-propelled vehicle itself and not a towed trailer. The federal rule in 49 CFR 390.21 does not name an exact spot, so the door is a common choice and not a legal requirement. Pick a clean, flat area where the lettering can be read from 50 feet.

What the rule says and does not say about location

The marking has to appear on both sides of the self-propelled commercial motor vehicle. That is the whole location rule. It does not mention a door, the cab, the sleeper, the box or a height above the road (49 CFR 390.21).

FMCSA's own news release says carriers must display their name and USDOT number on both sides of the power unit (FMCSA). The marking can be painted on or be a removable device, such as a magnetic sign, as long as it meets the same contrast, legibility and both-sides requirements. We cover that in our magnetic signs guide.

Because the rule is silent on the exact spot, the real question is practical: will the lettering read from 50 feet in daylight where you put it? Our USDOT number display rules page has the short version of the rule.

A placement checklist for the door

1. Choose a flat, clean panel. Skip door seams, handle recesses, ridges, rivets and trim. Vinyl lifts and digits break up where the surface changes shape.
2. Stay clear of glass, mirror arms and chrome. Reflections can wash out lettering in direct sun.
3. Use the same spot on both doors. The rule asks for both sides, not matching spots. Matching positions are our suggestion, because the pair is easier to find and looks deliberate.
4. Think about eye level. Choose a spot a person standing beside the truck can read without crouching, and above the zone where wheel spray and mud land.
5. Measure for the whole decal. If you add the company name, city or an MC line, the full rectangle has to fit the flat area, not just the number.
6. Clean and dry the surface first. Our install guide walks through application.
7. Test before you peel. Tape a paper mockup in place and read it from 50 feet, as described in how big USDOT numbers need to be.

The door builder shows your decal on a truck door before you order, which helps with step 5.

Special cases

Pickups with temporary signs

In its 2000 final rule, FMCSA answered a request about pickups this way: motor carriers who use their personal pickups for business purposes can affix temporary signs and remove them when necessary (Federal Register). A removable sign still has to be on both sides and pass the same contrast and 50-foot tests. Whether your pickup needs a number at all depends on its weight rating and use, which we explain in do pickup trucks need DOT numbers.

Rented and leased trucks

For a rental of 30 calendar days or less, the truck may carry the lessor's name and USDOT number instead, if the rental agreement has the details the rule lists and is carried on the vehicle (49 CFR 390.21(e)).

For leased equipment hauling property, the rule says the carrier that acquires the equipment identifies it under Part 390 during the lease (49 CFR 376.11). FMCSA guidance adds that the markings of the carrier responsible for the operation of the vehicle must be displayed at the time of transportation (FMCSA). If you are leased on, ask the carrier who supplies the markings before you buy decals.

Trailers

The marking rule applies to the self-propelled vehicle. FMCSA's 2000 rule did not extend it to trailers (Federal Register). Unit numbers, weight and VIN lettering on trailers are separate decisions, covered in DOT requirements for trailers.

Before you order

If you are not sure your truck needs a number at all, start with who needs a USDOT number. Once you know, the Custom USDOT Logo carries name, city, USDOT and MC on one decal, and the USDOT decal carries the number alone. Decals are priced per decal, so order two for both doors.