1 Answer

From the IRS website:

Lost or Misplaced Your EIN?

If you previously applied for and received an EIN for your business, but have since misplaced it, try any or all of the following actions to locate the number:
Find the computer-generated notice that was issued by the IRS when you applied for your EIN. This notice is issued as a confirmation of your application for, and receipt of an EIN.
If you used your EIN to open a bank account, or apply for any type of state or local license, you should contact the bank or agency to secure your EIN.
Ask the IRS to search for your EIN by calling the Business & Specialty Tax Line at (800) 829-4933. The hours of operation are 7:00 a.m. - 7:00 p.m. local time, Monday through Friday. An assistor will ask you for identifying information and provide the number to you over the telephone, as long as you are a person who is authorized to receive it. Examples of an authorized person include, but are not limited to, a sole proprietor, a partner in a partnership, a corporate officer, a trustee of a trust, or an executor of an estate. http://www.irs.gov/Businesses/Small-Businesses-%26-Self-Employed/Lost-or-Misplaced-Your-EIN%3F