What is Form W-9?
Form W-9 collects a contractor's or vendor's name and taxpayer ID so the paying business can later issue a 1099. It's an internal form — it isn't sent to the IRS.
A W-9 is dead simple but easy to fumble on the tax-classification line. A single-member LLC that hasn't elected corporate treatment checks "individual/sole proprietor," not "LLC" — a mismatch there can cause the payer's system to reject your info and start backup withholding.
Who files it
Independent contractors, freelancers and vendors complete it when a client or business requests it before paying them.
When it's due
Form W-9 is generally due Before a business pays a contractor. Deadlines can move for weekends and holidays, so confirm the exact date for the current year on IRS.gov.
Key lines and parts
Here's what you'll actually fill in on Form W-9:
- Name and business name
- Federal tax classification (individual, LLC, S corp, etc.)
- Address
- Taxpayer Identification Number (SSN or EIN)
- Certification and signature
How to file
Fill it in and return it to the requesting business, which keeps it on file and uses it to prepare information returns like the 1099-NEC.