What Is the W-9 Form? A Step-by-Step Guide

Form W-9 is the IRS form a US person, such as a freelancer or contractor, uses to give a business their name, tax classification and taxpayer identification number (TIN). The business needs those details to file an information return, such as a Form 1099-NEC, for what it paid you. You fill it in, sign it where required, and give it to the business that asked for it, not to the IRS.

Billed publishes this page. It's general information about US federal tax, not tax advice. IRS quotes are from Form W-9 (Rev. March 2024), the IRS About Form W-9 page (last reviewed June 27, 2026) and the IRS Backup withholding page (last reviewed October 10, 2026), all opened on October 30, 2026. Ask your accountant how they apply to you. For the business's side, requesting the form and filing Forms 1099, see what is a 1099 form.

What the form is for (US)

The IRS says: "Use Form W-9 to provide your correct Taxpayer Identification Number (TIN) to the person who is required to file an information return with the IRS to report, for example:" Its examples start with "Income paid to you." and go on to real estate transactions, mortgage interest, secured property, canceled debt and IRA contributions.

The form itself lists information returns it's used for, and says the examples "include, but are not limited to, the following", among them:

• "Form 1099-MISC (various types of income, prizes, awards, or gross proceeds)."
• "Form 1099-NEC (nonemployee compensation)."
• "Form 1099-K (merchant card and third-party network transactions)."

It also says: "Use Form W-9 only if you are a U.S. person (including a resident alien), to provide your correct TIN."

How to fill out Form W-9, step by step

Quotes in each step are from Form W-9 (Rev. March 2024) and its instructions.

1. Line 1, your name. "You must enter one of the following on this line; do not leave this line blank. The name should match the name on your tax return." For a sole proprietor: "Enter your individual name as shown on your Form 1040 on line 1. Enter your business, trade, or "doing business as" (DBA) name on line 2."
2. Line 3a, your tax classification. "Check the appropriate box for federal tax classification of the entity/individual whose name is entered on line 1. Check only one of the following seven boxes." If you have an LLC, the form's notes on line 3a explain which box applies; ask your accountant if you aren't sure how your LLC is classified.
3. Your address, on the form's address lines.
4. Part I, your TIN. "If you are a sole proprietor and you have an EIN, you may enter either your SSN or EIN. If you are a single-member LLC that is disregarded as an entity separate from its owner, enter the owner's SSN (or EIN, if the owner has one)."
5. Part II, the certification. For payments to contractors, the form says: "For mortgage interest paid, acquisition or abandonment of secured property, cancellation of debt, contributions to an individual retirement arrangement (IRA), and, generally, payments other than interest and dividends, you are not required to sign the certification, but you must provide your correct TIN."
6. Give it to the business that asked. The form says: "Give form to the requester. Do not send to the IRS."

Backup withholding (US)

If the business doesn't get your TIN, it may have to hold back part of each payment. The IRS backup withholding page says: "There are situations when the payer is required to withhold at the current rate of 24 percent." Form W-9 says: "Payments you receive will be subject to backup withholding if:" Its reasons include:

• "You do not furnish your TIN to the requester;"
• "The IRS tells the requester that you furnished an incorrect TIN;"

The form also says: "You will not be subject to backup withholding on payments you receive if you give the requester your correct TIN, make the proper certifications, and report all your taxable interest and dividends on your tax return."

Keep your W-9 secure

A W-9 carries your SSN or EIN. The form's identity theft section says: "An identity thief may use your SSN to get a job or may file a tax return using your SSN to receive a refund." Send your W-9 only to a business you know is paying you, through a method you both trust.

Sample: what backup withholding would mean for one payment

The figures here are a sample for the 2026 tax year, invented for this example. They use the 24% rate the IRS backup withholding page states.

A freelance designer invoices a new client $2,500 and hasn't yet given the client a W-9, so in this sample the client has to apply backup withholding:

• Withheld and paid to the IRS: $2,500 × 24% = $600
• Paid to the designer: $2,500 − $600 = $1,900

Had the designer returned a completed W-9 with a correct TIN first, and no other backup withholding condition applied, the client would have paid the full $2,500. How withheld tax is credited on your return is a question for your accountant.

Where Billed fits

Billed's invoice software page says: "Invoice reports show which invoices are paid, partially paid or past due, and you can see who owes you money and send them a payment reminder." Its financial reporting page says: "All reports in Billed can be exported for use with your accountant, bookkeeper, or tax software." Those records help you check the totals on any Form 1099 your clients send you. See also what is self-employment tax, and if you're an employee rather than a contractor, what is a W-4 form.

Related Articles

• What Is a 1099 Form?
• What Is Self-Employment Tax?
• What Is a Schedule K-1 Tax Form?
• Cash vs. Accrual Accounting
• What Is an Excise Tax?

Frequently Asked Questions

What is a W-9 form used for?

The IRS says you use Form W-9 "to provide your correct Taxpayer Identification Number (TIN) to the person who is required to file an information return with the IRS". A business that pays you uses it to fill in information returns such as Form 1099-NEC.

Do I send my W-9 to the IRS?

No. Form W-9 says: "Give form to the requester. Do not send to the IRS."

Should a sole proprietor put an SSN or an EIN on a W-9?

Form W-9 says: "If you are a sole proprietor and you have an EIN, you may enter either your SSN or EIN."

What happens if I don't give a client my W-9?

Form W-9 says: "Payments you receive will be subject to backup withholding if:" One of the reasons it lists is "You do not furnish your TIN to the requester". The IRS says: "There are situations when the payer is required to withhold at the current rate of 24 percent." Ask your accountant how this affects you.