Both forms ask for your name, your address and a tax ID number, which is why people confuse them. They do different jobs for different people.
The short answer
Use a W-4 if you are an employee. Use a W-9 if you are paid as an independent contractor or another kind of non-employee. The person or company paying you will usually tell you which one they need.
What a W-4 does
An employee gives a Form W-4 to their employer to say how much federal income tax to withhold from each paycheck. It stays with the employer, and you can submit a new one when your situation changes, for example after a new job, a marriage or a new child.
What a W-9 does
A Form W-9 gives a payer your name and taxpayer ID number so they can report what they paid you. Nothing is withheld just because you filled it in. The exception is backup withholding, which can apply if you don't give a correct taxpayer ID number.
What happens at tax time
Employees get a Form W-2 from their employer, which employers generally have to provide by January 31. Contractors get a Form 1099-NEC from each client that paid them enough to be reportable. Either way, the payer files its copy, and you use your copy when you prepare your return.
Side by side
- Who fills it in: W-4 is for an employee. W-9 is for a contractor or other payee.
- Who receives it: W-4 goes to your employer. W-9 goes to the person or company that asked. Neither is sent to the IRS by you.
- What it controls: W-4 sets income tax withholding. W-9 supplies your taxpayer ID for reporting.
- Year-end form: W-4 leads to a W-2. W-9 leads to a 1099-NEC or similar.
If you aren't sure which one you are
Whether someone is an employee or a contractor depends on the actual working relationship, not just on the paperwork. The IRS publishes guidance on telling the two apart, and the payer decides which form to request. If you think you have been classified the wrong way, that is a question for the IRS guidance or a tax professional.
Fill either one in your browser
Both forms open in DocZap with their fields ready to type into, and nothing is uploaded. This is general information, not tax advice.
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