W-9 vs W-8 vs W-4: What’s the Difference and When to Use Each?

Introduction

Tax forms can feel like alphabet soup: W-9, W-8, W-4…
They sound similar but serve very different purposes. If you’ve ever paused mid-onboarding a contractor or employee and thought, “Wait, which one do I need?” you’re not alone.

In this guide, we’ll break down what each form is for, who needs to fill it out, and when to use it.

What Is a W-9 Form?

The W-9 (Request for Taxpayer Identification Number and Certification) is used by U.S. businesses to collect taxpayer information from freelancers, contractors, and vendors.

Who uses it? U.S. businesses hiring U.S. individuals/entities
Why? To collect the TIN (Taxpayer Identification Number) so you can issue a 1099-NEC at year-end
When? Before making payments

💡 Pro Tip: Always collect the W-9 before paying the contractor. It’s easier to follow up when you still hold the check.

What Is a W-8 Form?

The W-8 series is for non-U.S. persons or businesses. It certifies that the recipient is not subject to U.S. income tax withholding.

Who uses it? Foreign freelancers, agencies, or vendors
Why? To claim tax treaty benefits and reduce (or eliminate) U.S. tax withholding
Common types:
- W-8BEN: Individuals
- W-8BEN-E: Entities
- W-8ECI / W-8EXP / W-8IMY: Other specialized cases

❗Important: A U.S. business paying a nonresident must have a W-8 form on file to document withholding exemption.

What Is a W-4 Form?

The W-4 is for employees — not contractors.

Who uses it? U.S. employees working for a U.S. company
Why? To instruct the employer how much federal income tax to withhold from paychecks
Filed with: The employer, not the IRS

🚫 Do not use W-4s for contractors. If you’re hiring someone who sends you an invoice, stick with the W-9.

How to Collect These Forms Easily

Manually collecting forms via email or spreadsheets can lead to:

Missing forms
Outdated versions
IRS penalties at year-end

GetW9 automates this process:
✔ Secure W-9 requests
✔ Real-time tracking
✔ Centralized storage

Try it free → www.getw9.tax

The form you need depends entirely on who you’re paying and where they’re from.
Understanding the difference between a W-9, W-8, and W-4 isn’t just about compliance, it’s about protecting your business.