An employer identification number (EIN) and a federal tax ID number are the same thing. The Internal Revenue Service is the government agency responsible for issuing an EIN to companies.
An EIN number is a 9-digit number designed to identify a company to the IRS in the same way a social security number is used to identify a person. Companies are required to present an EIN to establish a business bank account.
Sole proprietorships are not required to get a federal tax ID number. A sole proprietor may use his social security number as opposed to a federal tax ID number. However, it is probably a good idea for a sole proprietor to apply for an EIN because using a social security number for business purposes may expose the business owner to fraud, as explained by the Financial Web website.
All nonprofits, including charities, must have an EIN. Each branch of a charity carries its own individual EIN.
Form SS-4 must be completed and filed with the IRS in order for a company to get an EIN. The IRS allows companies to apply on the IRS website, by telephone, fax or by mail. The IRS does not charge a fee to issue an EIN.