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🇺🇸 United States

W-9 Taxpayer Identification

Taxpayer ID for Contractors and Vendors

Easy ~5 min TaxContractorFreelanceIRS

/ What is this form?

Form W-9 is a one-page IRS form used by US businesses and individuals to request your Taxpayer Identification Number (TIN) before making payments to you. It is not filed with the IRS directly — instead, the business keeps it on file and uses the information to prepare 1099 forms at the end of the year, which are then reported to the IRS.

Hundreds of millions of W-9s are exchanged every year because they are required in virtually every contractor and vendor relationship. If you do any freelance work, consulting, rental income, or other self-employment, you will fill out W-9s regularly. Banks, brokerages, and real estate companies also collect them for interest, dividend, and proceeds reporting.

The W-9 is deceptively simple — it's just one page with a handful of fields — but Line 3 (Federal Tax Classification) confuses millions of people, especially LLC owners. Getting this wrong can cause tax reporting mismatches that trigger IRS notices.

/ Who needs this form?

  • Freelancers and independent contractors who will receive $600 or more from a single client in a year
  • LLC owners providing services to other businesses (even single-member LLCs)
  • Landlords receiving rental payments from business tenants
  • Anyone opening a bank or brokerage account where interest or dividends will be reported
  • Real estate sellers providing their TIN to settlement agents

/ What you need before you start

Your Social Security Number (SSN) or Employer Identification Number (EIN)
Your legal name exactly as it appears on your tax return
Your business name or DBA name (if applicable)
Your federal tax entity classification (Individual, LLC, Corporation, Partnership, etc.)
Your current mailing address

/ Step-by-step guide

1 Name (Line 1)
Enter your full legal name exactly as it appears on your tax return. If you are a sole proprietor or single-member LLC, this should be your personal name, not your business name.
2 Business Name (Line 2)
If you operate under a business name, DBA (doing business as), or disregarded entity name different from Line 1, enter it here. Leave blank if your business name is the same as your personal name.
3 Federal Tax Classification (Line 3)
Check the box that describes your tax entity type: Individual/sole proprietor, C Corporation, S Corporation, Partnership, Trust/estate, LLC, or Other. For LLCs, you must also specify the tax classification: C, S, or P (partnership). Single-member LLCs that have not elected corporate status check 'Individual/sole proprietor.'
4 Enter Your TIN (Part I)
Enter your Taxpayer Identification Number. For individuals and sole proprietors, this is your Social Security Number (SSN). For businesses, use your Employer Identification Number (EIN). Do not enter both.
5 Sign and Date (Part II)
Sign and date the certification. By signing, you certify that your TIN is correct, you are not subject to backup withholding, and you are a US person. Return the completed form to the requester — do NOT send it to the IRS.

/ Key fields explained

Field What to enter Common mistake
Line 1 – Name Your full legal name as shown on your Form 1040 or business tax return. For a sole proprietor: your personal name. For a corporation: the corporate name. Entering your business trade name (DBA) on Line 1 instead of your legal name — the legal name goes on Line 1, and the DBA goes on Line 2.
Line 3 – Federal Tax Classification Check exactly one box. Single-member LLCs without a corporate election: check 'Individual/sole proprietor or single-member LLC'. Multi-member LLCs: check 'Limited liability company' and write 'P' for partnership in the box. LLC owners checking 'Limited liability company' for a single-member LLC taxed as a disregarded entity — they should check 'Individual/sole proprietor or single-member LLC' instead.
Part I – Social Security Number Your 9-digit SSN in the format XXX-XX-XXXX. Only individuals and sole proprietors use SSN here. Entering an EIN for a sole proprietorship when you don't have one — if you are a sole proprietor without an EIN, use your SSN. Never enter a random number.
Part I – Employer Identification Number Your 9-digit EIN in the format XX-XXXXXXX. Use this for partnerships, corporations, and multi-member LLCs. Entering both an SSN and an EIN — use only one. If you have both, use the EIN for business payments.

/ Common mistakes to avoid

Entering the DBA or trade name on Line 1 instead of the legal name — trade names go on Line 2.
Single-member LLC owners checking the wrong LLC classification box — a disregarded SMLLC should be classified as Individual/sole proprietor.
Leaving the TIN blank and sending an incomplete form — payers must withhold 24% backup withholding if no valid TIN is provided.
Sharing your W-9 over unsecured email without encryption — your SSN can be intercepted by identity thieves.
Not updating your W-9 when your address, business structure, or TIN changes — this causes 1099 mismatches.

/ Frequently asked questions

Is the W-9 filed with the IRS?

No. The W-9 is given to the business or person paying you. They keep it on file and use your TIN to prepare 1099 forms that are reported to the IRS. You never send the W-9 to the IRS yourself.

What happens if I refuse to provide a W-9?

The payer is legally required to withhold 24% of every payment as backup withholding and send it to the IRS. You will receive the net amount and must reconcile the withholding on your tax return.

Do I need to fill out a new W-9 every year?

Not automatically — the W-9 stays valid until your information changes. If your name, address, TIN, or tax classification changes, you should submit an updated form to each payer.

How do I fill out Line 3 as an LLC?

Single-member LLCs not electing corporate status: check 'Individual/sole proprietor or single-member LLC'. Multi-member LLCs: check 'Limited liability company' and write 'P'. LLCs electing S-corp or C-corp status: check LLC and write 'S' or 'C'.