<P> The Employer Identification Number (EIN), also known as the Federal Employer Identification Number (FEIN) or the Federal Tax Identification Number, is a unique nine - digit number assigned by the Internal Revenue Service (IRS) to business entities operating in the United States for the purposes of identification . When the number is used for identification rather than employment tax reporting, it is usually referred to as a Taxpayer Identification Number (TIN), and when used for the purposes of reporting employment taxes, it is usually referred to as an EIN . These numbers are used for tax administration and must be not used for any other purpose . For example, the EIN should not be used in tax lien auction or sales, lotteries, etc . </P> <P> Similar in purpose to the Social Security number assigned to individuals, EINs are used by employers, sole proprietors, corporations, partnerships, non-profit organizations, trusts and estates, government agencies, certain individuals and other business entities . The IRS uses this number to identify taxpayers that are required to file various business tax returns . Individuals who are employers may choose to either obtain an EIN or use their Social Security number for the purpose of reporting taxes withheld on behalf of their employees . Contrary to some misconceptions, credit bureaus and credit issuers can tell the difference between SSNs and EINs . SSNs can be validated as to origin and state / year of issuance . The credit bureaus and issuers are highly trained in fraud detection, and increasingly sophisticated algorithms and protections are used . This is why the EIN is not considered sensitive information, and is freely distributed by many businesses by way of publications and the internet . </P>

How many digits in an employer federal identification number