If you don’t fill out a W-9 when a client or payer requests one, federal law requires them to withhold 24% of every payment they send you and forward it to the IRS as backup withholding. Many payers will also hold your invoices entirely until the form is on file, and the IRS can charge you a $50 civil penalty for each failure to provide a correct taxpayer identification number. Deliberately putting false information on the form pushes the consequences into felony territory.
The 24% Backup Withholding Kicks In Automatically
The most immediate consequence is money. When you don’t give a payer your taxpayer identification number on a W-9, the payer is required by statute to withhold 24% from every reportable payment until you fix it.1Internal Revenue Service. Backup Withholding This isn’t discretionary. The law lists four situations that force the payer’s hand: you failed to provide a TIN, the IRS told the payer your TIN is wrong, the IRS flagged you for underreporting interest or dividend income, or you didn’t certify that you’re not subject to backup withholding.2Office of the Law Revision Counsel. 26 USC 3406 – Backup Withholding
The practical effect is easy to see. A contractor billing $10,000 receives $7,600. The other $2,400 goes to the IRS. You get that money back eventually, because backup withholding is a prepayment of tax rather than a penalty, and you claim it as a credit when you file your annual return.1Internal Revenue Service. Backup Withholding But “eventually” can mean months. For a freelancer or small operator running on tight margins, losing a quarter of every deposit to a delayed refund is where the actual damage lands.
Many Payers Simply Won’t Pay You
Backup withholding assumes the payer is willing to pay you at all. In practice, most companies aren’t. A business that pays a contractor without collecting a W-9 exposes itself to penalties for filing incorrect information returns and for not implementing backup withholding, so accounts-payable departments treat a missing W-9 as a hard stop. Your invoice sits.
There’s another wrinkle. If the payer has no W-9 and no other documentation of who you are, IRS rules require them to presume you may be a foreign person, which triggers separate and higher withholding rules under Chapter 3.3Internal Revenue Service. Instructions for the Requester of Form W-9 (03/2024) Between the reporting penalties and the presumption problem, “just pay them anyway” is not a path most payers will take.
The IRS Can Fine You Directly
Separate from anything the payer does, the IRS can penalize you for the failure itself. The fine is $50 for each failure to provide a correct TIN, capped at $100,000 in a calendar year.4Office of the Law Revision Counsel. 26 USC 6723 – Failure to Comply With Other Information Reporting Requirements This one is a straight penalty. You don’t recover it at tax time the way you recover backup withholding.
The number climbs sharply if you put something false on the form. Providing a false statement on a W-9 that reduces the amount withheld from your payments carries a $500 penalty per false statement when there’s no reasonable basis for the information.5Office of the Law Revision Counsel. 26 USC 6682 – False Information With Respect to Withholding A common trigger: checking the box certifying you’re not subject to backup withholding when the IRS has already told you that you are.
Deliberate Falsification Becomes Criminal
The W-9 is signed under penalty of perjury. Willfully making a false statement on it falls under the federal fraud and false statements statute, which carries a fine of up to $100,000 for individuals or $500,000 for corporations, plus up to three years in prison.6Office of the Law Revision Counsel. 26 USC 7206 – Fraud and False Statements
The IRS doesn’t refer honest mistakes or late submissions to prosecutors. Criminal cases involve people who knowingly use fabricated TINs, borrow other people’s identities, or systematically certify false information to duck withholding. The statute is broad, though, and any willful misrepresentation on the form is potentially prosecutable.
How to Stop the Withholding Once It Starts
The fix depends on what caused the withholding in the first place.
You Never Submitted a W-9
Complete and sign the form with your correct TIN and full certifications, then send it to the payer. Once they have a valid W-9, they must stop backup withholding no later than 30 calendar days after receiving your TIN.7Internal Revenue Service. Understanding Your CP2100 or CP2100A Notice Whatever was already withheld stays with the IRS until you claim it as a credit on your return.
The IRS Told the Payer Your TIN Is Wrong
When the IRS finds a name-and-TIN mismatch, it sends the payer a CP2100 or CP2100A notice. The payer then sends you a “B notice” asking you to correct the discrepancy. After a first B notice, providing the payer a corrected W-9 with the right TIN clears the problem. After a second B notice within three years, a fresh W-9 alone isn’t enough. You’ll need to send a copy of your Social Security card, or, for a business, an IRS Letter 147C confirming your EIN.8Internal Revenue Service. Backup Withholding “B” Program
If you don’t respond at all, the payer is required to start backup withholding no later than 30 business days after receiving the IRS notice.7Internal Revenue Service. Understanding Your CP2100 or CP2100A Notice Ignoring B notices is how a paperwork issue turns into months of reduced payments.
You Were Flagged for Underreporting
If the IRS flagged you for failing to report interest or dividend income, submitting a new W-9 won’t help. The certification on the form specifically asks whether the IRS has notified you about underreporting, so you can’t honestly sign it until the underlying issue is cleared with the IRS directly.
If the Reason You’re Hesitating Is Your SSN
People often resist filling out a W-9 because they don’t want to hand their Social Security number to every client. That’s a reasonable concern. A copy of your SSN sits in the filing system of every business you’ve ever invoiced, and any of those systems can be breached.
If you operate as a sole proprietor, you can apply for an EIN from the IRS and use that on your W-9 instead of your SSN.9Internal Revenue Service. Form SS-4 – Application for Employer Identification Number The application is free and takes minutes online. Your income still flows through to your personal return; the EIN just keeps your SSN off other people’s paperwork.
One Boundary: The W-9 Is Only for U.S. Persons
The W-9 is for U.S. citizens, resident aliens, and domestic entities. If you’re a foreign individual or foreign entity receiving U.S.-source payments, the correct form is W-8BEN for individuals or W-8BEN-E for entities.10Internal Revenue Service. About Form W-8 BEN, Certificate of Foreign Status of Beneficial Owner for United States Tax Withholding and Reporting (Individuals) Skipping that paperwork is worse than skipping a W-9. Without a valid W-8BEN, the default withholding rate under Chapter 3 of the Internal Revenue Code is 30% of the gross payment.11Internal Revenue Service. Tax Withholding Types A tax treaty may reduce or eliminate that rate, but only if you file the form and claim the benefit.