A Texas Department of Transportation (TXDOT) number is a unique identifier issued to commercial vehicle operators by the state of Texas. If you have a TXDOT number, you are required to display the number prominently on your vehicle. A TXDOT number is similar to the U.S. Department Of Transportation (USDOT) number. However, the rules for each differ slightly.


The USDOT number is a unique number assigned to a company by the federal government. The number is used to monitor safety records, perform federal compliance reviews and is also used during inspections. If you haul interstate cargo or carry passengers or hazardous substances, you are required by law to display a USDOT number on your vehicle.


A TXDOT number is required if you operate almost any commercial vehicle in the state of Texas; you don't have to be hauling passengers or hazardous goods to need a number. In addition to the federal requirements, you are required to register for a TXDOT number if you transport cargo and the gross weight is more than 26,000 pounds, if you transport household goods for money or if the owner of the commercial vehicle is not a U.S. citizen.


According to the Texas Transportation Code, Chapter 643, Section 643.002, if your vehicle is registered under the federal Unified Carrier Registration Act, you are not required to obtain a USDOT. In addition, several classes of vehicle are exempt from getting a TXDOT number. The exemptions include: cotton vehicles, private school, nursing home, hotel and day care vehicles, private carrier vehicles licensed under Chapter 42, Alcoholic Beverage Code and tow trucks.


In order to apply for a TXDOT, you must already have a USDOT. To obtain a TXDOT number, fill out application Form 1899 (see Resources) and file the appropriate fee. The fees range from $5 to $100 (as of November 2010), depending on how long you want the TXDOT number for.