Hello. Thank you for your question.
No, you do not need to apply for a new EIN.
However, you may need to change the type of tax return you file. Single member LLCs often choose to be a disregarded entity - meaning they file their annual activity on their form 1040. Now that you have 2 members, you will need to use form 1065 (partnership) or form 1120S (S-Corporation).
Check your records and see if you filed form 8832, which tells the IRS what tax form you are going to use for your LLC. Here is a link to the form so you can see what it looks like. http://www.irs.gov/pub/irs-prior/f8832--2012.pdf
I hope this answers your question. Please let me know if you need additional information. I appreciate feedback. Thank You!
No you do NOT need to change the ID#
Paul, is there anything else I can help you with?
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