In the state of California you can not have two LLC`s with the same name even if they are in two different counties. Remember the LLC is registered at a State level and not with the county.
So the LLC name has to be unique, that is why when you file for an LLC or corporation they ask you for three Business Names:
1. Your first choice is what you want to name your business
and two extras with alternates in case your first choice of business name is taken.
Now to answer your second question, yes you can name your LLC or Corporation a different name and still do business under another.
Let me give you an example:
Let`s say you name your LLC "xyz LLC" but you want to do business under a ficticious name of "fortune cookies express", all you need to do is go to the county that you live in and apply for an FBN or also known as a DBA Filing "doing business as".
All you need is your LLC`s Articles (I don`t know if an LLC has articles of Incorporation) but if they do, you bring that with you to the county registrar and fill a simple self explanatory form.
If you don`t want to go through all that hassle you can use this company www.filedba.com
they will do everything from standing in line to putting it on the newspaper for you. be aware that in the state of California you have to advertise your DBA filing on the newspaper for 30 days and then go back and show them proof.
MY advice to you is, if you want to save time use filedba they are reliable and you never have to go down to the County registrar.
I`m not sure which county you live in, but in Los Angeles County the fees are as follow : $23.00 for the filing plus one registrant and $4.00 for each additional dba or registrant, in your case since you are going to register the dba under your LLC it would be: $23.00 and 1 registrant being the LLC.
I hope this helps you
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