A Form W-9 is a one-page IRS form a client asks you to fill in before they pay you. It gives them your legal name, your tax classification and your taxpayer identification number (TIN), so they can report what they paid you on a 1099-NEC after the year ends. You don’t send it to the IRS and you don’t owe anything for filling it in. The current version is the March 2024 revision.

Why a client asks for one

A business that pays an independent contractor for services has to file a 1099-NEC once the year’s payments reach the threshold, which is $2,000 for payments made in 2026. To do that they need your TIN, and the W-9 is how they get it in writing. Most clients ask at onboarding, before the first invoice, because chasing contractors for W-9s in January is miserable. Being asked doesn’t mean you’ll get a 1099, and not getting one doesn’t mean the income isn’t taxable: every dollar goes on your Schedule C either way.

Filling it in, line by line

  • Line 1, name: the name on your tax return. For a sole proprietor or a single-member LLC, that is your own name.
  • Line 2, business name: your trade name or LLC name, if you have one. Leave it blank otherwise.
  • Line 3a, tax classification: tick one box. Freelancers and single-member LLCs taxed the default way tick individual/sole proprietor. An LLC that elected S-corp treatment ticks LLC and writes “S”; a multi-member LLC usually writes “P” for partnership.
  • Line 3b: only for partnerships, trusts and estates with foreign partners or owners. Most freelancers skip it.
  • Line 4, exemptions: for corporations and certain organizations. Individuals leave it blank.
  • Lines 5 and 6: the address where you want the 1099 mailed.
  • Part I, TIN: your Social Security number or your EIN. A single-member LLC taxed as a sole proprietorship uses the owner’s SSN or EIN, not a separate LLC number, unless it has elected corporate treatment.
  • Part II: sign and date it. You are certifying the TIN is correct and that you aren’t subject to backup withholding.

SSN or EIN?

Either is valid for a sole proprietor. An Employer Identification Number is free from the IRS, takes a few minutes online, and means your Social Security number isn’t sitting in a dozen clients’ shared drives. You don’t need employees to get one. Once you have it, use the same EIN on every W-9 so the 1099s you receive match what you report.

Sending it safely

A filled-in W-9 is exactly what identity thieves want. Before you send one, confirm the request really comes from your client: a W-9 request from an unfamiliar address, or one that arrives with an urgent payment story, is a common scam. Use the client’s vendor portal or an encrypted file link rather than a plain email attachment, and send it only to the person who pays you.

What happens if you don’t

A client who can’t get a valid TIN from you may have to start backup withholding: holding back 24% of each payment and sending it to the IRS. You would get credit for it on your return, but it’s cash you don’t have until then. Filling in the form takes five minutes. Then keep a record of what each client pays you as it arrives, so the 1099s you get in January are a check, not a surprise: what to do when the 1099s arrive.

Questions, answered

Do I have to fill out a W-9?

If a client who pays you for services asks for one, yes. They need your taxpayer ID to file a 1099-NEC, and without it they may have to withhold 24% of your payments as backup withholding.

Does a W-9 mean I’ll be taxed on that client’s payments?

You owe tax on self-employment income whether or not you fill in a W-9 or receive a 1099. The W-9 only lets the client report what they paid you.

Should I put my SSN or an EIN on a W-9?

Either works for a sole proprietor or single-member LLC. A free EIN from the IRS keeps your Social Security number off clients’ files.

Where do I send a W-9?

To the client who asked for it, through a secure channel. The W-9 is never sent to the IRS.

Sources

  1. About Form W-9, Request for Taxpayer Identification Number and Certification — IRS. The form, its purpose and the current revision.
  2. Instructions for the Requester of Form W-9 — IRS. Line-by-line rules, including line 3b and disregarded entities.
  3. Backup withholding — IRS. When payers must withhold, and the 24% rate.
  4. Get an employer identification number — IRS. Applying for a free EIN online.