USDOT Number Size Requirements

Are you confused about DOT Number size requirements? You're not alone. Carriers across the US have expressed frustration about finding the requirements. Well, look no further. The mission of our organization is to help carriers maintain great standing with the DOT.

That’s why we communicate with the DOT and FMCSA every week. We recognize that a violation of a rule or regulation can cause a lot of harm. Trucking companies lose money whenever a violation takes place. That’s why we’ve listed standard USDOT Number size requirements below. Follow the requirements as best you can. Doing so will help your company maintain good standing with the USDOT and FMCSA.

The Size Requirements for Any DOT Number

US Department of Transportation Numbers serves as identification tools. The purpose of the Numbers is to maintain records on every commercial motor vehicle. That’s why specifications exist about the appearance and size of DOT Numbers. Drivers and trucking professionals have to display the numbers in a certain format. The US government makes a very clear demand.

It is that DOT Numbers and MC Number on commercial trucks should appear legible during the day. In fact, the DOT Numbers must have minimum visibility from 50 feet away. The minimum height of DOT numbers is 2 inches. 

Almost all carriers display DOT Numbers on both doors of each vehicle. This is because the USDOT demands that the DOT Number gets displayed on the power unit. (“Power unit” refers to a vehicle door or cab door.) It’s best to display your DOT number on both sides of every CMV. These size requirements apply to every carrier that operates in interstate commerce. Vehicles that do not meet these requirements will get put out of service.

More DOT Number Size Requirements

US carriers should keep in mind that the lettering of the DOT Numbers should get displayed in bold. The coloring of the numbers should contrast with the color of the surrounding surface. You do not want to risk applying DOT Number lettering that’s the same color as a vehicle. Plus, high contrast will help ensure that there is visibility. Our DOT experts recommend making your lettering of the DOT Numbers as large as you can. Doing so will help ensure that you avoid potential fines due to infractions. But don't make your DOT Numbers so large that they cause confusion. The key is for the number size to exceed two inches in length. 

CMVs should have a marking containing the name of the business entity. That business entity controls every motor carrier operation. You can also display your “doing business as”/DBA name if you have one. If so, use the business entity name that’s listed within your MCS-150 form. Do your commercial motor vehicles sometimes drive through hazardous weather conditions?

If so, our organization recommends using durable data plates. Most get produced using anodized aluminum that is photosensitive. These data plates can prevent your asset identification numbers from getting destroyed.

How Do Most Carriers Take Care of DOT Number Size Requirements? 

Many carriers display their DOT Numbers using standard block letters. But that doesn’t mean it’s prohibited to use other fonts. Make sure that the writing appears legible. If you have any doubt, considering using a different font. The majority of carriers use vinyl lettering for all their vehicle lettering needs. Make sure that you use high-quality vinyl lettering that is long-lasting. 

The DOT lettering for most trucking companies is in black or white. You can use any color that you want. The key is to make sure that the lettering contrasts with the vehicle color. For example, say you operate with a lot of chrome. Your DOT Number lettering can also be chrome. But only if there is distinct color contrast. Do you have vehicles in your fleet that are new or painted in recent months? If so, our experts suggest that you add your company’s contact information. You can even consider applying both the contact information and logo at once.

Who Is Exempt From a DOT Number?

Here is the type of trucking professional that isn’t required to hold a CDL. It is a driver that operates a vehicle with the GVWR/GCWR/GVW/GCW under 26,001 pounds. These drivers transport animals, vehicles, or personal goods through interstate/intrastate trucking commerce.

Do You Need Personal Numbers for DOT?

Say that someone uses a truck or trailer for personal reasons. The trailer is below the 10,000-pound threshold. This means that person doesn’t need to file for a DOT number. But say that person uses his/her truck/trailer for commercial reasons. This means that the individual has to file for a DOT Number. Exact state requirements vary when it comes to filing for a DOT Number.

How Do I Find the DOT Number on My Truck?

Here is where your USDOT Number must get displayed. It must appear on both sides of the motor area or coach area. The height of the DOT Number must exceed two inches. The Number must be visible from 50 feet away. Print your DOT Numbers using colors that will contrast with truck backgrounds.

Does My DOT Number Expire?

The FMCSA and USDOT do not focus on when DOT numbers expire. Instead, they focus on updates. That’s why the FMCSA requires all companies to update their DOT information every two years. Failure to do so can result in large fines and penalties.

Contact Us for More Information About DOT Number Size Requirements

Do you need more information about DOT Number size requirements? If so, our experts are standing by and ready to assist right now. We’ve helped countless carriers across the US take care of DOT requirements. And our team is only a phone call away from helping your employees. Our dedicated staff can walk you through all regulations for displaying USDOT Numbers. We can even provide a list of suggested products that can help ensure compliance. Please also browse our website to view more USDOT information. Our experts look forward to helping your transportation business succeed.

Did You Know

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Question The interstate moving industry in the United States maintains regulation by the FMCSA, which is part of the USDOT. With only a small staff (fewer than 20 people) available to patrol hundreds of moving companies, enforcement is difficult. As a result of such a small staff, there are in many cases, no regulations that qualify moving companies as 'reliable'. Without this guarantee, it is difficult to a consumer to make a choice. Although, moving companies can provide and often display a DOT license.

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