This guide explains what tax form you need to complete (W-8 or W-9), why it’s required, and how to fill out the relevant form correctly. Completing the correct form is required to remain eligible for payments. We cannot provide personalized tax advice. For questions about your tax situation, please consult a licensed tax professional.

Why do I need to complete a tax form?

Tax forms are required by law so we can:

• Report payments correctly to tax authorities
• Ensure you are paid without delays
• Confirm your tax residency and status

If a valid tax form is not on file, we may be required to pause tasking or withhold payments.

Will completing this form affect how much I’m paid?

• W-9 filers: Payments are usually not taxed upfront, but your earnings may be reported to the IRS.
• W-8 filers: Some payments may be subject to U.S. tax withholding, depending on IRS rules and tax treaties.

Which form do I need to complete?

Complete a W-9 if:

• You are a U.S. person, and
• You are a U.S. citizen, U.S. permanent resident (green card holder), or
• You are considered a U.S. tax resident (If you live in the U.S. most of the year and receive payments here, you are usually considered a U.S. tax resident.)

Complete a W-8 if:

• You are not a U.S. person for tax purposes, and
• You live and pay taxes outside the United States

If you are an international student on an F-1 or J-1 visa, please double check with a tax professional or immigration specialist prior to filling out a tax form. 

W-9 form (U.S. persons)

What is a W-9?

The W-9 provides your taxpayer information so payments can be reported to the U.S. Internal Revenue Service (IRS).

What information do I need to complete a W-9?

• Full legal name (as shown on your tax return)
• Tax classification (individual, LLC, etc.)
• Social Security Number (SSN) or Employer Identification Number (EIN)
• U.S. address
• Signature and date

How do I choose the correct tax classification on a W-9? 

Your tax classification tells the IRS how you are taxed. Two common options are the Individual / Sole Proprietor and Single-Member LLC.  Select the option that best matches your situation:

Individual / Sole Proprietor

• Choose this if you are working as yourself
• Includes freelancers, contractors, and sole proprietors
• Most individual fellows should select this option

Single-Member LLC

• Choose this if you own an LLC with one owner
• In most cases, you will still check “Individual / Sole Proprietor” and write the LLC name if requested
• Use your SSN or EIN depending on how your LLC is set up

Common W-9 mistakes to avoid

• Using a nickname instead of your legal name
• Entering an incorrect SSN/EIN
• Leaving the form unsigned
• Selecting the wrong tax classification

W-8 form (non-U.S. persons)

What is a W-8?

The W-8 confirms that you are not a U.S. tax resident and helps determine whether U.S. tax withholding applies. Most fellows will complete Form W-8BEN, which is for individuals. 

What information do I need to complete a W-8?

• Full legal name
• Country of citizenship
• Country of tax residence
• Permanent address (outside the U.S.)
• Foreign tax identification number (if applicable)
• Date of birth
• Signature and date

Common W-8 mistakes to avoid

• Listing a U.S. address as your permanent address
• Leaving required fields blank
• Forgetting to sign and date the form
• Submitting an expired form

 W-8 forms generally expire after 3 years and may need to be resubmitted.

Form 1099 and Form 1042-S

Do I get a 1099 if I filled out a W-8 or W-9?

If you completed a W-9, you may receive Form 1099-NEC if your payments meet IRS reporting requirements. Companies are generally required to report payments of $600 or more made to U.S. independent contractors. Not all W-9 filers will receive a 1099.

Why am I receiving a Form 1099-NEC?

You receive a Form 1099-NEC because you were paid as an independent contractor during the tax year and your payments are required to be reported to the IRS.

When will I receive my 1099?

Form 1099-NEC is issued by January 31 of the following year, as required by the IRS.

Will I receive a tax form if I completed a W-8?

If you completed a W-8, you will not receive a Form 1099. Instead, non-U.S. contractors who receive U.S.-source income may receive Form 1042-S, depending on IRS reporting rules and whether any U.S. tax was withheld.

What is Form 1042-S?

Form 1042-S reports U.S.-source income paid to non-U.S. individuals and any U.S. tax withheld, if applicable. It serves a similar reporting purpose to a 1099 but is used for non-U.S. taxpayers.

When will I receive Form 1042-S?

Form 1042-S is generally issued by March 15 of the following year.