What is a W-9 Form and How Do You Complete It?

As a business owner, you’re responsible for many year-end forms — and Form W-9 is one of the most important. Knowing when and how to use it helps you avoid mistakes, stay compliant, and keep your vendor payments on track.

When you know how to complete and review a W-9 properly, you reduce risk, avoid delays, and stay confident in your compliance.

To help simplify your year-end process, we’ve outlined everything you need to know about Form W-9, including answers to our most frequently asked W-9 questions.

Form W-9: What it Is and Why it Matters

A W-9 is an IRS form used to request and certify a person’s or business’s taxpayer identification information for the purpose of accurate reporting. If your business pays independent contractors, freelancers, or vendors $600 or more in a calendar year, you’ll likely need a W-9 from them to determine if a Form 1099 is required.

But more than just another tax requirement, Form W-9 is a foundational tool to help protect your business from reporting risks, IRS penalties, and delays in vendor payments.

Frequently Asked Questions

What information is required on Form W-9?

A W-9 helps ensure the correct tax identification information is on file for accurate income reporting and backup withholding if necessary. Utilizing the W-9 form helps guarantee that all critical information about the vendor is presented in a way that aligns with the standards set by the IRS, facilitating accurate and efficient tax reporting.

These are the primary sections on Form W-9:

Name: List the name of the taxpayer. It must be written correctly in order to meet the requirements of the IRS. The vendor must write their full legal name.
Business Name: If filing as a business, DBA name, trade name, or disregarded entity name, list that information here. (This section does not apply to individuals.)
Address:The W-9 form must also include the vendor’s current address, including number, street, and apartment or suite number, as well as the city, state, and ZIP code.
Taxpayer Identification Number: If the name on line one is an individual, the vendor should provide their Social Security Number (SSN). If the name on line one is an entity, they should provide their Employer Identification Number (EIN). If an individual is a resident alien and not eligible for an SSN, they should use their IRS individual taxpayer identification number (ITIN).
Federal Tax Classification: In this section, the taxpayer must designate themselves as an individual/sole proprietor, C corporation, S corporation, partnership, trust/estate, LLC (with additional classification required), or other (with additional information required).
Exemptions: Only specific businesses or entities will need to fill out the exemptions section. If a business or entity is exempt from backup withholding, they will need to list their code here.
Certification: A W-9 form must be signed and dated to be considered complete. Keep in mind that this is a legal document, so all information must be accurate.

Who needs to complete Form W-9?

The general rule is simple: if you’re paying someone $600 or more for services as part of your trade or business, request a W-9. That includes:

Freelancers (e.g., a graphic designer who creates your logo)
Independent contractors (e.g., a marketing consultant or web developer)
Vendors or small businesses that aren’t incorporated

However, there are exceptions. For example, if a vendor is a C corporation or S corporation, or is classified as a nonprofit, you may not need to issue a 1099 — but a W-9 still confirms that status for your records.

Does a W-9 need to be updated annually?

Not necessarily — but it’s smart to treat it like a living document. Ask for an updated W-9 if any of the following change:

Name or business name
Address
Federal tax classification
Taxpayer Identification Number (TIN)

Even if no changes occur, many businesses proactively request updated W-9s annually to ensure their records are accurate and ready for 1099 season.

Best Practices for Completing Form W-9

Contact your vendor and request a Form W-9 before you make your first payment.

Don’t wait until year-end to gather missing information. Building W-9 collection into your vendor onboarding workflow ensures completion and certification of the form, which you need as a business owner for tax purposes.

Review Form W-9s as you receive them.

Make sure all the required boxes are completed and the taxpayer has signed the form. This will be key if the IRS contacts you regarding incorrect information. It's much easier to request corrections now than it is when you're racing to meet 1099 deadlines in January.

Maintain secure, organized records.

W-9s contain sensitive data. Make sure they’re securely stored and easy to retrieve. You don’t need to file W-9s with the IRS — but you must be able to provide them if requested.

Streamline your processes with digital solutions.

Software programs and apps can be used to request taxpayer identification for individuals and businesses and collect W-9 information from your vendors. Additionally, your accounting program may have options to input W-9 data for storage and recovery. These systems may also allow you to run reports and identify missing information.

Tackling this list monthly or quarterly makes this task simpler and less overwhelming than reviewing it annually. Similar programs and apps can be used to file your information returns at year-end, but only if your W-9 information has the correct taxpayer identification number and other pertinent details.

You can use the IRS e-services to check the individual TIN of a vendor. If you receive information that you are unsure about from a vendor, you can verify that the TIN matches their name here.

Quick W-9 Compliance Checklist

☑ Always collect a W-9 before first payment

☑ Verify that all fields are completed and signed

☑ Request a new W-9 annually, or if the vendor’s name, entity type, or TIN changes

☑ Keep W-9s securely on file – don’t send to the IRS (unless requested)

☑ Use IRS TIN Matching to verify that the info you received from your vendor matches the IRS records.

Protect What Drives Your Growth

Form W-9 is essential for year-end tax compliance by business owners and independent contractors. A thorough understanding of the form and requirements is critical to proper reporting and a successful year-end.

The IRS W-9 Form, revised in March of 2024, can be accessed on the IRS website and you can find instructions here.

If you need help, Eide Bailly’s experienced certified public accountants and business advisors are here to provide you with the support you need at year-end and all year long.