What is the primary purpose of a Form W-9?

The primary purpose of a Form W-9 is to confirm the taxpayer identification number (TIN). This form is typically used by businesses to collect the identifying information of their contractors, vendors, or other payees. By providing the TIN, the individual or entity helps the requester to correctly report income paid to them on tax documents, such as the Form 1099. This is crucial for the IRS to track income and ensure proper tax compliance.

Having an accurate TIN is essential for accurate tax reporting and helps avoid potential issues with withholding taxes. While the other options involve aspects of tax withholding or exemptions, they do not encapsulate the primary function of the W-9, which is about establishing the correct identification number for reporting purposes.