> ## Documentation Index
> Fetch the complete documentation index at: https://docs.tesouro.com/llms.txt
> Use this file to discover all available pages before exploring further.

# TaxIdentificationNumberOutput

> The tax identification number for a business entity, including type and last 4 digits.

`OBJECT`

The tax identification number for a business entity, including type and last 4 digits.

## Fields

<ResponseField name="type" type="TaxIdentificationNumberType">
  The type of the tax identification number (e.g., EIN, SSN, ITIN).

  <Expandable title="Possible enum values">
    <ResponseField name="EIN" type="enum">
      Employer Identification Number.
    </ResponseField>

    <ResponseField name="SSN" type="enum">
      Social Security Number.
    </ResponseField>

    <ResponseField name="TIN" type="enum">
      Tax Identification Number.
    </ResponseField>
  </Expandable>
</ResponseField>

<ResponseField name="last4" type="String">
  The last 4 of the tax identification number.
</ResponseField>