It is possible to have multiple lines of business under the same LLC and EIN. You would not necessarily need to create separate business bank accounts. If you do create multiple lines of business under the same LLC, for your own clarity I would recommend that you use a bookkeeping method that allows you to track the revenue and expenses associated with each line of business as well as your general unallocated corporate overhead.
You may wish to register a fictitious business name for each line of business. You could use these names for purposes such as marketing and professional licensure.
One disadvantage of having multiple lines of business under the same LLC is that, while the LLC limits personal liability for losses and risks of the LLC, it may not protect each line of business from the losses and risks of the others. Please consult a legal professional for further information.
