Definition
The IRS form a freelancer, contractor, landlord, or investor hands to whoever will pay them, not to the IRS. It supplies your legal name, address, and taxpayer identification number (a Social Security number or an employer identification number) and certifies that you are not subject to backup withholding, so the payer can report what it paid you on a 1099 at year end.
Why it matters
A W-9 request is the signal that no tax will be withheld from the payments that follow, so the tax is yours to plan for. Only give one to a party that is actually paying you; a W-9 request from a stranger is a common identity-theft setup.
Example
A freelance editor signs a $12,000 contract and the client asks for a W-9 before paying the first invoice. The editor receives the full $12,000 across the year with nothing withheld, the client files a 1099-NEC reporting it, and the editor covers the tax through quarterly estimated payments. Had the editor refused to supply a W-9, the client would have been required to hold back a flat percentage of every payment as backup withholding.
Put it into practice
Related terms
This definition is educational, not financial, legal, or tax advice. U.S. rules and limits change; verify time-sensitive details with official sources. See our disclaimer.