An EIN is an Employer Identification Number given to companies by the IRS for identification and tax purposes. An EIN number can be obtained by applying online, by phone, by mail or by fax to the IRS. If you lose your EIN after you have been give one, there are a few ways to figure out what it is.
Locate the notice sent to by the IRS after you applied for your EIN. This notice will have your EIN on it because it serves as a receipt for your EIN.
Call your bank if you opened a business account there using your EIN.
Call the state or city licensing office if you used your EIN to apply for a license.
Call the Business & Speciality Tax Line of the IRS at (800) 829-4933. Request that they look up your EIN for you.
Give the person you speak to at the IRS your business information to prove that you are a person who is authorised to receive business information.