LLC issues you a Tax ID number and insulates your personal SSN from business liablities.
There are advantages over DBA.
You get the tax ID number from the IRS, but you don't need to form an LLC to get your TIN. You can apply using a DBA as a sole proprietor. And yes, you should never put your SSAN out there in any filing with the FMCSA.
As
@mndriver posted, that
CRAP you hear on radio and TV about an LLC or incorporating a business protecting you from anything is a load of pure grade A BS. Its all about fleecing an inexperienced new business owner, and providing you with more start-up expenses.
As a business owner
and driver, you are responsible for what happens when you drive. Having some kind of LLC or S-corp structure doesn't protect you from liability over what happens on the road. However, no one can sue you and take a retirement account... y'all should consult an attorney here.
Incorporating as an LLC taxed as an s-corp will save you some tax money,
eventually. You need to make enough consistently that the savings from the self employment tax on the profits you don't pay yourself as salary is large enough to offset the accounting costs associated with doing payroll. Most likely, this will take awhile... and may never happen considering how many folks run themselves right out of business too.
Its simple enough to change from a sole proprietorship to a corporation when you start making enough money. It does require changing your MCS-150 filing with the FMCSA, getting a new TIN and changing your bank accounts, plus jumping through the state hoops to form the LLC. But you certainly don't need this to start business, and all the extra expense to do this. You're going to have more than enough expenses to git going without spending abunch of money on unnecessary corporate BS.