To fill out Form W-9, you enter your legal name on Line 1, any business or trade name on Line 2, check one box for your federal tax classification on Line 3, list your mailing address on Lines 5 and 6, write your Social Security number or EIN in Part I, and sign the certification in Part II. The completed form goes to the business that asked for it, not to the IRS. Learning how to fill out Form W-9 correctly matters because a mismatch between your name and taxpayer identification number, or a refusal to hand the form over at all, can trigger 24% backup withholding on every payment you receive.
What the Form Is For
A W-9 exists so a payer can collect your taxpayer identification number (TIN) and later report what they paid you to the IRS on a form like the 1099-NEC or 1099-MISC. You’ll get a W-9 request when you do freelance or contract work, but the form also applies to real estate transactions, mortgage interest, cancellation of debt, and IRA contributions.1Internal Revenue Service. About Form W-9, Request for Taxpayer Identification Number and Certification
If you’re a regular employee on payroll, this isn’t your form. Employees fill out a W-4, which tells an employer how much tax to withhold from each paycheck. A W-9 doesn’t cause any withholding by itself; it’s an information document.
Line 1 and Line 2: Name and Business Name
Line 1 asks for the name shown on your tax return. For an individual, that’s your legal name. For a single-member LLC, which the IRS treats as a disregarded entity, put the owner’s name on Line 1, not the LLC’s name.2Internal Revenue Service. Instructions for the Requester of Form W-9 This is the mistake people make most often, and it creates a name-TIN mismatch that can delay processing or generate IRS notices.
Line 2 is for a business name, trade name, or disregarded-entity name that differs from what’s on Line 1. If you’re a sole proprietor working under your own legal name with no DBA, leave Line 2 blank.
Line 3: Federal Tax Classification
Check one box on Line 3. The options are:
- Individual or sole proprietor, the default for most freelancers and independent contractors.
- C corporation or S corporation, for incorporated businesses.
- Partnership, for entities with two or more owners taxed as a partnership.
- Trust or estate, for fiduciary entities.
- Limited liability company, which requires an additional letter showing whether the LLC is taxed as a C corporation (C), S corporation (S), or partnership (P).
The box you pick determines how the IRS treats income reported under your TIN. An LLC that recently elected S corporation status has to reflect that here; the wrong box can mean the payer applies incorrect tax rules on their information returns.2Internal Revenue Service. Instructions for the Requester of Form W-9
Line 4 holds exempt payee codes and FATCA codes. If you’re an individual freelancer or sole proprietor, you almost certainly leave it blank. Those codes exist for institutional and corporate payees such as tax-exempt organizations, government entities, publicly traded corporations, and registered brokers.2Internal Revenue Service. Instructions for the Requester of Form W-9
Lines 5 and 6: Address
Lines 5 and 6 collect your current mailing address. This is where the requester will send your 1099 at year’s end. An outdated address means the form goes to the wrong place, and because the IRS also gets a copy, you can end up with unreported income on your record simply because you never saw what was filed.
Part I: Taxpayer Identification Number
Part I is where you write your TIN. For most individuals, that’s your Social Security number. Businesses generally use an employer identification number (EIN). Federal law requires you to furnish this number to anyone who must file an information return reporting payments to you.3Office of the Law Revision Counsel. 26 USC 6109 – Identifying Numbers The number must match the name on Line 1. A mismatch is one of the fastest ways to trigger backup withholding.
Part II: Signing the Certification
Part II is where the form gets legal weight. By signing, you certify under penalties of perjury that your TIN is correct, that you’re a U.S. person, and that you’re not subject to backup withholding. The “under penalties of perjury” language is not decorative. A willful false certification on backup withholding, such as claiming you’re not subject to it when you know you are, carries a criminal penalty of a fine up to $1,000, imprisonment up to one year, or both.4Office of the Law Revision Counsel. 26 USC 7205 – Fraudulent Withholding Exemption Certificate or Failure to Supply Information
Backup Withholding: When It Applies
Backup withholding is the IRS’s fallback when it doubts a payee is reporting income correctly. When it applies, the payer withholds 24% of each payment and sends it to the IRS.5Internal Revenue Service. Backup Withholding You can become subject to it if:
- You don’t provide a TIN when asked.
- The IRS notifies the payer that the TIN you gave is incorrect.
- The IRS tells the payer to start withholding because you underreported interest or dividends on a prior return, which happens only after the IRS sends you four notices over at least 120 days.
- You fail to certify that you’re not subject to backup withholding.
If you refuse to hand over a completed W-9, the payer is generally required to begin backup withholding immediately on any reportable payments.6Internal Revenue Service. Topic No 307, Backup Withholding The 24% comes off the top of every payment until the situation is resolved. You eventually get credit for the withheld amount on your tax return, but in the meantime the money is with the government.
Penalties for Missing or Incorrect Information
Failing to provide a correct TIN when properly requested carries a $50 penalty per failure, capped at $100,000 per year. These amounts are set by statute and are not adjusted for inflation.7Internal Revenue Service. 20.1.7 Information Return Penalties The penalty can be waived if you show the failure was due to reasonable cause rather than willful neglect.8Office of the Law Revision Counsel. 26 USC 6724 – Waiver; Definitions and Special Rules The criminal exposure from a false certification, described above, sits on top of that.
Where the Form Goes
The completed W-9 goes directly to the requester. It is never mailed or submitted to the IRS. The requester keeps it in their records and uses the information to generate a 1099 when payments cross the reporting threshold, which is $600 for most nonemployee compensation on Form 1099-NEC.9Internal Revenue Service. Instructions for Forms 1099-MISC and 1099-NEC
Because a W-9 contains your name, address, and Social Security number or EIN, treat delivery as an identity-security question. Encrypted email, password-protected files, and hand delivery are safe. Standard email and public fax offer little protection if the document is intercepted. If a requester asks you to send a completed W-9 through an unsecured channel, push back.
Many businesses now collect W-9s through electronic vendor portals. The IRS allows this if the system verifies the identity of the person submitting the form, captures the same information as the paper version, can produce a hard copy on IRS request, and requires an electronic signature under penalties of perjury using the same language as the paper form.2Internal Revenue Service. Instructions for the Requester of Form W-9
When to Submit a New W-9
Send a fresh W-9 whenever the information on your last one changes. The usual triggers are a legal name change, a new mailing address, a different TIN (such as switching from a Social Security number to an EIN after incorporating), or a change in tax classification. An LLC that elects S corporation treatment should notify every payer so the correct classification appears on future information returns.
Get the update to your payers before the end of the calendar year if you can. If a requester generates a 1099 using your old name or address, you end up with mismatched records at the IRS, and correcting a filed information return after the fact is an administrative headache. Most businesses request fresh W-9s annually or when they suspect a change, but don’t wait to be asked. If something changed, send the update.