How to Fill Out a W-9 Form
Step-by-Step Guide

How to Fill Out a W-9 Form

The complete step-by-step guide to filling out IRS Form W-9 correctly — for freelancers, contractors, and small businesses.

Last reviewed: April 2026

If you are an independent contractor, freelancer, or run a small business, you will inevitably be asked to fill out a W-9 form. Companies use this form to collect your tax information so they can report the payments they make to you to the IRS.

⚠️ Important:Filing a W-9 incorrectly can lead to "backup withholding," where the payer is required to withhold 24% of your payment and send it straight to the IRS.
1

Enter Your Name (Lines 1 & 2)

On Line 1, enter your full legal name exactly as it appears on your federal tax return. If you are a sole proprietor, this is your personal name — not your business name.

Line 2is for your business name or "Doing Business As" (DBA) — only if it differs from Line 1. LLCs and corporations should enter their registered entity name here.

W-9 Line 1 Sole Proprietor name vs Line 2 LLC Business Name visual guide
2

Select Your Federal Tax Classification

This is where most mistakes happen. Check one box that matches your business entity:

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Individual / Sole Proprietor — Freelancers working under their own name, or single-member LLCs not electing corporate status.
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C Corporation / S Corporation — Incorporated businesses.
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Partnership — Multi-member businesses that aren't corporations.
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LLC — You must also specify the tax classification: C, S, or P (Partnership).
3

Provide Your Mailing Address

Enter the address where you want your tax documents (such as Form 1099-NEC) to be mailed. Make sure this is a current, deliverable mailing address. A P.O. Box is acceptable.

4

Enter Your Taxpayer Identification Number (TIN)

You must provide either your Social Security Number (SSN) or your Employer Identification Number (EIN).

SSN
Use your SSN if you are a sole proprietor or individual freelancer. The IRS generally prefers the SSN in this case.
EIN
Use your EIN if you are a corporation, partnership, or LLC. You must use an EIN if you have employees.
W-9 Part I — SSN vs EIN decision guide showing which number to use
5

Sign the Certification (Part II)

By signing the W-9, you are certifying under penalty of perjury that:

  1. The TIN you provided is correct.
  2. You are not subject to backup withholding.
  3. You are a U.S. citizen or other U.S. person.
  4. The FATCA code(s) entered are correct (if applicable).

⚡Common W-9 Mistakes to Avoid

⚠️

Wrong Tax Classification

Checking "Individual" when you have an S-Corp or LLC. Match your entity exactly.

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Using a Nickname

Writing "Mike" instead of "Michael" — your name must match your tax return.

✍️

Missing Signature

Failing to sign and date the document makes it completely invalid.

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Incorrect TIN

Double-check your SSN or EIN. Errors cause payment delays and IRS notices.