You get a DOT number by registering with the Federal Motor Carrier Safety Administration (FMCSA) and submitting a USDOT application (usually the MCS‑150 form) either online or by mail.

What a DOT number is (quickly)

A DOT number is a unique ID the FMCSA assigns to your trucking or passenger‑carrier business so regulators can track safety, insurance, inspections, and compliance. If you operate commercial vehicles in interstate commerce (or in some states, even just intrastate) over certain weight limits or carrying passengers/hazmat, you’re required to have one.

Step‑by‑step: how do I get a DOT number?

  1. Confirm you actually need one
    • You generally need a DOT number if you: operate commercial vehicles over a certain weight, carry paying passengers, or haul hazardous materials in interstate commerce.
 * Many new trucking companies, owner‑operators, and hotshot operations fall into this category.
  1. Gather your basic business info
    Have this ready before you start the application:
 * Legal name and any DBA (doing‑business‑as) name of your business
 * Business address, phone, and email
 * Social Security Number or business tax ID (EIN)
 * Type of operation: for‑hire carrier, private carrier, passenger carrier, government, etc.

 * Operation type: interstate or intrastate only

 * Cargo you plan to haul (general freight, household goods, reefer, hazmat, etc.)

 * Vehicle info: number of vehicles, types (truck, tractor, trailer, bus), and whether you own or lease them

 * Driver info: number of drivers, number with CDLs, and whether you use family drivers only, employees, etc.
  1. Choose how you’ll apply (online or mail)
    • Online (fastest):
      • Go to the FMCSA registration system (Unified Registration System) and create an FMCSA user account.
   * Once logged in, start a new USDOT registration, which walks you through the application questions step‑by‑step.

   * Your DOT number is usually issued immediately at the end of the online process, though it may take up to about 20 days before it’s fully active for interstate operations.

 * **By mail (slow):**
   * Download the MCS‑150 form (or MCS‑150B/MCS‑150C if you haul hazmat or are an intermodal equipment provider).

   * Fill it out by hand and mail it to FMCSA; this can take several weeks before you get your number.
  1. Fill out the application (MCS‑150 series)
    In the online or paper form, you’ll be asked to enter:
 * Business identity (name, address, EIN/SSN)
 * Company operation (for‑hire/private, passengers/freight, government/tribal, etc.)
 * Type of business (solo owner‑operator, partnership, corporation, LLC)
 * Operation classification (interstate, intrastate hazmat, intrastate non‑hazmat)
 * Cargo classifications (general freight, building materials, refrigerated food, vehicles, waste, etc.)
 * Number and type of vehicles you will use (straight trucks, tractors, trailers, buses)
 * Whether vehicles are owned or leased
 * Number of drivers and CDL drivers
 * Estimated annual mileage and where you operate

If you haul hazardous materials or are an intermodal equipment provider:

 * Use MCS‑150B (USDOT + hazmat) or MCS‑150C (USDOT + intermodal), as required.
  1. Submit and check status
    • Online: when you finish and submit, you’re usually given a DOT number right away on the confirmation screen.
 * Mail: processing can take several weeks; expect delays compared to online filing.

 * Once issued, you can verify your DOT number and its status through FMCSA’s public lookup tools.
  1. Display and maintain your DOT number
    • You must display your DOT number on both sides of each commercial vehicle, in clear, contrasting letters, visible from a distance.
 * You also need to keep your DOT record up to date by filing periodic MCS‑150 updates, usually every two years, or whenever key information changes.

How long and how much?

  • Time:
    • Online applications usually provide a DOT number immediately, but full interstate authority can take up to around 20 days.
* Mailed applications can take up to about six weeks.
  • Cost:
    • The DOT number itself is typically free, but you may have other required fees like Unified Carrier Registration (UCR), BOC‑3 processing agent, and insurance filings, depending on your operation.

Simple example

Imagine you’re starting a one‑truck hotshot business crossing state lines:

  • You decide you need a DOT number because your truck and trailer combination exceeds the weight threshold and you operate interstate.
  • You gather your LLC documents, EIN, business address, driver and truck details.
  • You create an FMCSA account, complete the MCS‑150 questions online, submit, get your DOT number on screen, then schedule your decals so it’s displayed on your truck before you haul your first load.

Forum‑style closing note

If you’re asking “how do I get a DOT number” because you’re just now stepping into trucking or hotshot work, the core move is: create an FMCSA account, complete the MCS‑150 online, and then make sure you meet all the extra requirements (insurance, UCR, BOC‑3, state permits) before you start rolling. The DOT number is only one piece of your compliance puzzle.

Bottom note: Information gathered from public forums or data available on the internet and portrayed here.