A Taxpayer Identification Number or TIN is an identifying number used for tax purposes in the United States. It is also known as a Tax Identification Number or Federal Taxpayer Identification Number. It may be assigned by the Social Security Administration

Social Security Administration

The United States Social Security Administration is an independent agency of the United States federal government that administers Social Security, a social insurance program consisting of retirement, disability, and survivors' benefits...

 or by the IRS (Internal Revenue Service

Internal Revenue Service

The Internal Revenue Service is the revenue service of the United States federal government. The agency is a bureau of the Department of the Treasury, and is under the immediate direction of the Commissioner of Internal Revenue...

.)

A TIN may be

• a Social Security number
  Social Security number
  In the United States, a Social Security number is a nine-digit number issued to U.S. citizens, permanent residents, and temporary residents under section 205 of the Social Security Act, codified as . The number is issued to an individual by the Social Security Administration, an independent...
  
   (SSN)
• an Individual Taxpayer Identification Number
  Individual Taxpayer Identification Number
  An Individual Taxpayer Identification Number is a United States tax processing number issued by the Internal Revenue Service. It is a nine-digit number that begins with the number 9 and has a range of 70 to 99 in the fourth and fifth digit, example 9XX-70-XXXX or 9XX-99-XXXX...
  
   (ITIN)
• an Employer Identification Number
  Employer identification number
  Applicable to the United States, an Employer Identification Number or EIN is the corporate equivalent to a Social Security Number, although it is issued to anyone, including individuals, who has to pay withholding taxes on employees.-Other names:Also known as the Tax Identification Number ,...
  
   (EIN), also known as a FEIN (Federal Employer Identification Number)
• an Adoption Taxpayer Identification Number, used as a temporary number for a child for whom the adopting parents cannot obtain an SSN
• a Preparer Tax Identification Number
  Preparer Tax Identification Number
  The Preparer Tax Identification Number is an identification number that all paid tax return preparers must use on U.S. federal tax returns or claims for refund submitted to the Internal Revenue Service...
  
  , used by paid preparers
  Tax preparation
  Tax preparation is the process of preparing tax returns, often income tax returns, often for a person other than the taxpayer, and generally for compensation. Tax preparation may be done by the taxpayer with or without the help of tax preparation software and online services...
  
   of U.S. tax returns
  Tax return (United States)
  Tax returns in the United States are reports filed with the Internal Revenue Service or with the state or local tax collection agency containing information used to calculate income tax or other taxes...
  
  

SSNs are used by individuals who have the right to work in the US.

ITINs are used by aliens

Alien (law)

In law, an alien is a person in a country who is not a citizen of that country.-Categorization:Types of "alien" persons are:*An alien who is legally permitted to remain in a country which is foreign to him or her. On specified terms, this kind of alien may be called a legal alien of that country...

who may or may not have the right to work in the US, such as aliens on temporary visas and non-resident aliens with US income. Often the reason why people need the identification number is because they have been advised by a bank that no account will be opened without it, even if it is requested by a non-profit organization.

EINs are used by employers, sole proprietors, corporations, partnerships, non-profit associations, trusts, estates of decedents, government agencies, certain individuals, and other business entities.

External links

• IRS website: Taxpayer Identification Numbers