The Federal Employer Identification Number (EIN) must be obtained by almost all businesses, whatever their form, and whether or not the business will ever hire employees. The exception is the entrepreneur who runs a sole proprietorship with no employees. He or she can use their Social Security number.
The EIN is the equivalent of a business’s Social Security number, and will be used on just about any document relating to the business, including license and permits applications, bank accounts, loan applications, etc.
The EIN is easy to obtain. You can file IRS Form SS-4 by mail or go online to www.irs.gov.