Understanding DOT Number Size Requirements: A Complete Guide

Veterans of the trucking industry know the importance and role of DOT numbers in protecting roadways, drivers, and cargo. Many vehicles used for the transportation of passengers and goods must display their DOT numbers in plain view. But what are the DOT number size requirements for your vehicle?

Once you register for a USDOT number, you’ll complete numerous other steps to secure your place as a trucker. Correct number placement is part of the process. Federal Motor Carrier Authority Filings created the following guide to help you comply with those display requirements. 

What Is a DOT Number?

The Federal Motor Carrier Safety Authority serves as a branch of the Department of Transportation. Its role is to ensure all companies and individual participants within the transportation industry comply with its strict safety regulations. It assigns DOT numbers to most people employed within the industry. 

Most drivers engaging in interstate commerce or passenger transportation must display their assigned numbers in visible locations on their vehicles. Does your vehicle fit those requirements?

Which Vehicles Need a Displayed Number?

If your vehicle fits one of the following descriptions, it must sport a visible number decal:

• It transports hazardous materials, such as flammable or radioactive substances.
• It services 15 or more passengers who pay for transportation.
• It hauls over 10,000 pounds of cargo during a shipment. 

You must also display the number for any type of interstate commerce. While this broadly covers all travel across state lines, it applies to same-state routes with shipments originating in a different state. 

Before you apply for a DOT number, you must acquire insurance coverage from a qualified provider. Then, you’ll submit your application, receive your number, and begin the new entrant process. 

Why DOT Numbers Are Important

Your DOT number signifies your operating authority. You significantly limit your career opportunities without one. However, it also serves other pertinent purposes listed below. 

Safety Audits

A DOT officer performs audits to ensure drivers comply with the required safety regulations outlined by the FMCSA. During these audits, they check:

• The state of the vehicle
• The driver’s qualification file
• Electronic logs detailing hours of service and other logistics
• Previous incidents and audit scores 

This information helps the officer get a bigger picture of how well the driver or company complies with the FMCSA over time. 

Access and Store Safety Information

Anyone can access a carrier’s final safety ratings via the SAFER website. This information helps vendors and shippers choose trustworthy trucking companies with longstanding compliance reputations. You can also use this site to learn about companies you’d like to apply to.  

Ensure Compliance

Finally, the USDOT number ensures every participant plays by the same rules in the trucking industry. Displayed decals keep all drivers and carriers accountable for their actions and safety responsibilities. Public accountability makes DOT number size requirements even more valuable. 

Displaying Your DOT Number

Where should you place your all-important decal bearing your unique USDOT number? Onlookers must be able to see the sticker from at least 50 feet away during daylight hours. Therefore, you must ensure a certain level of visibility with placement, size, and color.

Appropriate Display Locations

Drivers must place their decals on their vehicles’ power units. A power unit is the part of the vehicle that houses the engine. For example, a semi-truck should display the sticker somewhere on the driver's compartment. Pickup trucks, buses, and similar vehicles have more space display options since they have fully attached bodies compared to semis pulling trailers. 

Place the decal on either side of the power unit. This ensures that other drivers can easily identify your vehicle from both sides. 

Decal Colors & Font Recommendations

Since your decal must be visible, its color must significantly contrast the color of your truck. For example, a navy blue, black, or brown truck should have a white DOT decal. Trucks sporting light colors need black decals. 

You must also design your decal with the font details in mind. Choose bold lettering that stands out from any other decals you have. Select a plain, easily legible font rather than an elaborate but unclear option. 

DOT Number Size Requirements

Finally, remember that you should easily read your decal from at least 50 feet away. Choose letters of at least two inches in height to ensure visibility from a distance. You should leave enough room for your motor carrier number as well since many vehicles must display an MC decal. 

Apply for Your Number Using FMCA Filings’ Solutions

Although DOT number size requirements seem cut and dry, other related topics are not. Keeping your permits and documents organized or planning for how long it takes to get a DOT number depends on multiple factors. FMCA Filings ensures a smooth application process followed by streamlined updates and access. 

Connect with an online representative now to learn how to open your DOT portal.