Form W-9 Definition

Short Definition
Form W-9 is also known as Request for Taxpayer Identification Number (TIN) and Certification. It is an informational form available through the Internal Revenue Service (IRS) and used to obtain taxpayer information for financial and business purposes.
Extended Definition
The Request for Taxpayer Identification Number (TIN) and Certification is simply an official document meant to convey specific information between two parties. It is most commonly used when an independent contractor has provided goods or services for a business and that business needs identifying information in order to report payments to the IRS. Form W-9 is not filed with the IRS. The requester retains the form for tax purposes.

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