An Employer Identification number (EIN) is to a business what a Social Security number is to the individual. It is used on all tax-related correspondence including tax returns and quarterly tax remittances.

In some limited instances, a small business owner may use his or her Social Security number instead of an EIN. If you are a sole proprietorship (unincorporated and not a partnership) and do not have employees and are not required to collect sales tax or excise tax, you may use your Social Security number instead of an EIN when filing tax returns. However, any business that has employees, remits payroll taxes, pays excise taxes, or is incorporated or has formed a partnership must have an EIN.

To get an EIN, you need to contact the Internal Revenue Service (IRS) or Social Security Administration and complete an SS-4 form. An EIN application can be submitted by phone, fax, mail, or online. For more information, visit the IRS Web site at: Internal Revenue Service Web site