W-9 Form
Also known as: Form W-9 · tax ID form · W9
Definition
Form W-9 is an IRS form that freelancers provide to clients, confirming their name, business structure, and Taxpayer Identification Number (TIN, usually SSN or EIN). US-based clients request a W-9 before paying a freelancer, so they can issue a 1099-NEC at year-end.
Detailed Explanation
Every US freelancer should have a completed W-9 ready to send to new clients. The W-9 includes: your legal name (or business name if using an LLC), business structure (sole proprietor, LLC, S-Corp, etc.), and TIN (Social Security Number for sole props, EIN for LLCs/S-Corps). Clients need this information to issue your 1099-NEC in January. Keep your W-9 updated — if you change your business structure or address, update the form. W-9s should be sent securely (not over unencrypted email) because they contain sensitive tax ID information. Many invoicing platforms let you upload your W-9 once and include it with every invoice.
Freelancer Example
A freelance copywriter sends their W-9 to a new corporate client before starting a $5,000 project. The client uses the W-9 to set up the freelancer in their payment system and will issue a 1099-NEC at year-end. Without the W-9, the client would withhold 24% backup withholding from payments.