What is a TIN?

A Taxpayer Identification Number, or TIN, is an identification number used by the IRS for the administration of tax laws. Some types of TINs are as follows:
* Social Security Number (SSN) is a TIN for an individual person
* Employer Identification Number (EIN) is a TIN for a company/corporate entity
* Individual Taxpayer Identification Number (ITIN) is a TIN for individuals who do not have and do not qualify for SSNs, but must pay taxes in the US
* Preparer Taxpayer Identification Number (PTIN) is a TIN for a person or company who prepares taxes on behalf of others
* Adoption Taxpayer Identification Number (ATIN) is a temporary TIN for children in the process of being adopted but cannot get a SSN before taxes are due (the ATIN has been discontinued)