Form W-9, formally called the Request for Taxpayer Identification Number and Certification, is the IRS document businesses use to collect a contractor's or vendor's tax details before paying them. If you freelance, do contract work, or receive certain other types of payments, you have probably filled one out already, whether you realized what it was for or not.
Unlike most tax paperwork, the W-9 never goes to the IRS directly. It moves between two private parties: the person or business paying you, and you. The company that hires you keeps it on file and later uses the information to prepare a Form 1099 (or sometimes a 1098), which does get sent to the IRS along with a copy to you.
When a Business Asks You for This Form
Any time a company pays a nonemployee $600 or more in a year, it has to file Form 1099 NEC, and it needs your taxpayer information to do that correctly. That covers independent contractors and freelancers, but the list of triggers is longer than most people expect. You might also be asked to complete a W-9 for royalty payments, speaker fees, certain real estate transactions, mortgage interest payments, cancellation of debt, contributions to an individual retirement account, or the abandonment or acquisition of secured property.
Only U.S. persons fill out this form. That includes individuals, resident aliens, corporations, partnerships, domestic trusts, and estates. If you are a foreign contractor working with a U.S. company, you would generally use a different form instead.
Filling Out the Form Section by Section
The W-9 is available directly from the IRS website and is broken into three parts. The first section asks for basic identifying information: your name as it appears on your tax return, any business or