Short version: A W-9 gives the brand your name and taxpayer number so it can report what it pays you. It goes to the brand, never to the IRS. If a brand pays you $2,000 or more for your work in 2026, a 1099-NEC follows by January 31.
The W-9 is usually the first tax form a deal brings with it. It's one page to fill in, plus five pages of instructions. It's also the first piece of paper that treats your name like a business.
What the form asks for
The top half is who you are. Line 1 is your name, the one shown on your tax return.
Line 3a is your tax classification. The first box is "Individual/sole proprietor," which is an athlete paid in their own name with no company in between.
Line 5 is your address. The instructions say why it matters: it's "where the requester of this Form W-9 will mail your information returns." The requester is the brand. The information return is the 1099.
Part I is your TIN, short for taxpayer identification number. For an individual, the form says, that's "generally your social security number." A sole proprietor with an EIN, a business number from the IRS, may enter either one.
Part II is a signature "under penalties of perjury," which means a false statement can carry legal consequences. You certify that the number is correct, that you aren't subject to backup withholding, and that you're a U.S. citizen or other U.S. person.
For pay for your services, the instructions say the signature itself isn't required unless the IRS has told you a number you gave before was wrong. The correct number is required either way.
Why the brand wants it
The form's own purpose section is plain about it. A business that has to file an information return with the IRS "must obtain your correct taxpayer identification number" to report "the amount paid to you."
The Taxpayer Advocate Service, the IRS's own advocate office, says what happens on the other end. The IRS "uses this information to match your reported income when you file your tax return."
So a W-9 isn't a contract, and it doesn't change what the deal pays. It's how the money you're paid gets tied to your name in the IRS's records.
The W-9 doesn't decide what you owe. It decides whose name the payment is reported under.
Where it goes
Right on the form, in the top corner: "Give form to the requester. Do not send to the IRS." The brand keeps it in its own files.
Before it files, a payer can check your name and number against IRS records with a service the IRS calls TIN matching. A name that doesn't match its number is what that check is built to catch.
The form also names a limit on the brand. If a requester "discloses or uses TINs in violation of federal law," it may face civil and criminal penalties.
What happens without it: backup withholding
This is the part that stings. The form says a payer must, under certain conditions, "withhold and pay to the IRS 24% of such payments." Nonemployee pay is on the list. So are royalties.
It applies if you don't give your number, if you don't certify it when required, or if the IRS tells the brand the number is wrong. On a $5,000 payment, that's $1,200 sent to the IRS and $3,800 to you.
It isn't a fine. The IRS's backup withholding page says the amount withheld is reported on your return for the year, as federal income tax withheld. It counts toward what you owe. It just isn't in your account until you file.
If you're waiting on a number, the form lets you write "Applied For." The requester's instructions add a catch: for nonemployee pay, backup withholding starts "immediately, even if the payee has applied for and is awaiting a TIN."
There's also a $50 penalty for each failure to give a correct number, unless the failure is due to reasonable cause and not to willful neglect.
What comes next: the 1099
The W-9 is the setup. The 1099 is the report. The IRS's 2026 instructions say a business files Form 1099-NEC for pay "of $2,000 or more" to someone who isn't its employee, for services.
That line was $600 through 2025. The IRS says the new $2,000 amount "may be adjusted for inflation beginning in calendar year 2027." The same change raised the line for backup withholding on those payments.
The brand sends your copy and files the IRS copy by January 31. Your copy may show your number truncated, with part of it hidden. The copy filed with the IRS can't be truncated.
Not every deal lands on a 1099-NEC. Royalties go on Form 1099-MISC from $10. A payment made by card or through a payment network is reported on Form 1099-K by the company that processed it, not by the brand.
And a deal under $2,000 is still income. The Taxpayer Advocate Service puts it in one line: "Any income from NIL activities, including non-cash, is considered taxable income." What you owe on it depends on your own situation.
A W-9 or a W-4
The Taxpayer Advocate Service names both. In most instances, it says, a deal comes with a W-9. If you're "deemed to be an employee," you fill out a W-4 instead, so an employer can withhold income tax from your wages.
That's the difference you feel in your account. On a W-9 deal, the IRS's backup withholding page says, the payer "doesn't generally withhold taxes," because you're expected to report and pay them when you file.
Your number on a form
A W-9 carries your Social Security number to whoever asks for it. The form's instructions have a section on identity theft, and it says the IRS "does not initiate contacts with taxpayers via emails."
What Leave does with this
Upload the contract and Leave reads the payment terms back in plain words: how much, when, and who pays. The payment dates go on Home.
Leave doesn't fill in your W-9 or file anything for you. It takes 0 percent of any deal. Your name is a business, and the paperwork that comes with it is yours to decide on. Every source is linked at the bottom.
Questions people ask
Do I have to put my Social Security number on a W-9?
The form asks for your taxpayer identification number. For an individual that's generally the Social Security number. A sole proprietor with an EIN may enter either one, though the IRS says it encourages the SSN. Without a number, the payer may hold back 24 percent.
Does filling out a W-9 mean I owe tax?
No. The form doesn't set any tax. It gives the payer what it needs to report what it paid you. Deal income is taxable whether or not a W-9 or a 1099 ever changes hands.
Will every brand that gets my W-9 send me a 1099?
Not always. For 2026, a business files Form 1099-NEC once it pays one person $2,000 or more for services in the year. Royalties go on Form 1099-MISC from $10. Smaller deals are still taxable.
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