W-8 vs. W-9: which tax form do you need as an expat?

Written by  Andrew Coleman, CPA

Last updated Apr 30, 2026

The form you need depends on whether you are a US person for tax purposes or a foreign person, not on whether you live outside the US. That single rule resolves most W-8 vs. W-9 confusion before you go any further.

Quick answer:

• US person (citizen, green card holder, resident alien, domestic entity) signs Form W-9
• Foreign person signs the right Form W-8 subtype: BEN, BEN-E, ECI, EXP, or IMY
• Living abroad does not change a US citizen's status
• Wrong form can trigger 24% backup withholding or 30% NRA withholding

When a bank asks you to certify your status during account onboarding, the right form depends on tax classification, not your mailing address. Freelance marketplaces and US clients ask for W8/W9 paperwork for the same reason, since they need it for year-end reporting.

This guide covers the difference between W-8 and W-9, which form to file, what triggers withholding, and how to handle a request when one lands in your inbox.

What is Form W-9, and who should use it?

Form W-9, officially titled Request for Taxpayer Identification Number and Certification, is the form a US person uses to give their Taxpayer Identification Number (TIN) to anyone required to report payments made to them. The current IRS revision is dated March 2024, so check the date on whatever PDF you are signing.

The IRS frames eligibility around tax status, not residency. A US person includes US citizens living abroad, green card holders, resident aliens who pass the substantial presence test, and US domestic entities like LLCs and corporations.

The TIN you enter is your Social Security Number (SSN) if you are an individual, or your Employer Identification Number (EIN) if you are an entity.

Who usually asks for it? Clients, banks, brokers, marketplaces, and payment processors, basically anyone who has to report payments they make to you.

W-9 supports 1099 and other information return reporting; the payee does not file it with the IRS directly. The requester keeps the signed form on file and uses your information for year-end reporting, which puts it alongside the other US tax forms expats encounter.

The US tax form W-8/W-9 pair sits at the front of that chain: the payee signs, the payer files the downstream return.

What is Form W-8, and when is it used?

Form W-8 is not a single form; it is a family of five related certificates used to document foreign status, treaty claims, FATCA status, effectively connected income, or intermediary/flow-through status. Most are used by foreign persons, but Form W-8IMY can also be used by certain US branches and other intermediaries.

The shared purpose across the family is documentation. Without valid documentation, a US payer may have to apply 30% withholding to certain US-source payments subject to chapter 3 or chapter 4 rules until a valid W-8 is on file – which is why getting the right foreign withholding form in place matters before the first payment, not after.

The five subtypes cover different scenarios:

• W-8BEN: foreign individuals certifying foreign status and claiming treaty benefits
• W-8BEN-E: foreign entities certifying foreign status, treaty eligibility, and Chapter 4 (FATCA) classification
• W-8ECI: foreign persons (individuals or entities) whose US-source income is effectively connected with a US trade or business
• W-8EXP: foreign governments, international organizations, central banks, and tax-exempt organizations
• W-8IMY: foreign intermediaries, flow-through entities, and certain US branches passing payments to underlying owners

The right subtype depends on whether the signer is an individual or entity, whether the income is connected to a US trade or business, and whether a treaty applies. For ECI cases specifically, filing obligations and withholding treatment work differently from a standard W-8BEN scenario.

Whichever subtype applies, every W-8 or W-9 IRS form follows the same logic: it documents your tax status for the payer, who then decides withholding and reporting based on what you certify.

What are the 5 types of Form W-8, and who uses each one?

Each subtype handles a specific scenario, and picking the wrong one is the single biggest source of headaches in W-9 or W-8 form workflows. The table below summarizes who uses each form, the typical scenario, and the most common mistake.

Most US-source payments to foreign individuals run through W-8BEN. W-8BEN-E covers many foreign entity cases, but foreign governments and exempt organizations may need W-8EXP, intermediaries and flow-through entities may need W-8IMY, and foreign persons with effectively connected income may need W-8ECI instead.

The W-8ECI line is the most important one to flag because the original article had it slightly wrong. W-8ECI is for any foreign person beneficial owner of US-source income effectively connected with a US trade or business, individual or entity, not entities only.

W-8BEN-E is also more than just a treaty plus FATCA form: it covers beneficial ownership, hybrid entity claims, and substantial US owner disclosures for passive NFFEs.

W-9 vs. W-8: what are they, and what is the difference in tax status, withholding, and reporting?

The W-9 vs. W-8 comparison comes down to four practical questions: who signs the form, why a payer requested it, what default withholding kicks in if the form is missing or wrong, and how long the form stays valid. The table below covers all four side by side.

For most expats, the headline rule is simple: a US person, even one living abroad, signs a W-9; everyone else signs the W-8 form that fits their situation.

This is also where the W-8BEN vs. W-9 confusion shows up most often at the individual level. The two forms are not interchangeable, and a US client who collects the wrong one ends up with the wrong reporting and the wrong withholding rate at year-end.

When do you use IRS Form W-9 or W-8?

The decision tree for W-8 vs. W-9 form selection is straightforward once you anchor the question on tax status, not address. Start with one yes or no, and the right form follows.

Are you a US person for US tax purposes? (US citizen, green card holder, resident alien under the substantial presence test, or domestic entity)

• If yes, sign Form W-9, even if you live in Berlin, Tokyo, or Buenos Aires.
• If no, are you a foreign individual? Sign W-8BEN.
• If not, are you a foreign entity? Sign W-8BEN-E.
• If no, is the US-source income effectively connected with a US trade or business? Sign W-8ECI.

This also answers the four scenarios people actually search for. A US citizen in Spain working on Upwork signs a W-9. A foreign company invoicing a US client signs a W-8BEN-E. A nonresident with US rental income who elects ECI treatment signs a W-8ECI. A US LLC owner living abroad signs a W-9 for the US LLC.

US persons: when Form W-9 is the right form

Yes, US expats still use Form W-9. Americans abroad use Form W-9. Living in Lisbon or Mexico City does not change US tax status, so banks, US clients, and US-facing platforms should still receive a W-9 from you, not a W-8. The IRS classification of taxpayers treats US citizens as US persons regardless of where they live.

TFX client scenario: a US citizen running a freelance design business from Portugal received a W-8BEN request from a US client and signed it, thinking that living abroad made her a foreign person. The client issued a 1042-S instead of a 1099, and the IRS later flagged the income mismatch on her Form 1040.

The fix was a corrected W-9 going forward and an amended return for the affected year.

Foreign persons: when to use a W-8 form instead

Foreign persons are split into three buckets that decide which W-8 to sign. The treaty article, the FATCA box, and the reporting form all change with the subtype, so the W-9 or W-8 form decision on this side is really a decision among the W-8 subtypes.

The three main cases are:

• Foreign individual receiving US-source dividends, interest, or royalties: W-8BEN (compensation for personal services performed in the US uses Form 8233 or Form W-4, not W-8BEN)
• Foreign entity receiving US-source income: W-8BEN-E, including the FATCA classification
• Foreign person with effectively connected income (rental real estate election, US trade or business): W-8ECI

A foreign tech company invoicing a US SaaS client for software licensing signs W-8BEN-E and claims the relevant treaty article on royalties. If that same company instead operates a US branch with employees and inventory, the branch's income is ECI, and the right form becomes W-8ECI.

The W-8 vs W-9 decision for businesses follows the same rule: a domestic entity signs W-9, a foreign entity signs W-8.

How to fill out Form W-9 and W-8 forms correctly

Most filing problems come from two places: the boxes that change based on classification, and the certifications you sign without reading. The rest is mostly name, address, and TIN.

Using the wrong form, or filling out the right form incorrectly, can trigger the wrong withholding rate at the time of payment and the wrong information return at year-end. The two checklists below cover the W-9 and the W-8 family, starting with what matters and ending with what trips people up.

How to fill out Form W-9 correctly

Form W-9 looks short, but the federal tax classification box and the backup withholding certification are where most mistakes happen. The current IRS revision is dated March 2024, and the backup withholding rate is 24% if the form is missing, has the wrong TIN, or you are subject to backup withholding for another reason.

The fields that actually matter are your legal name, business name (if different), federal tax classification, address, and TIN. Individuals use SSN; entities use EIN. You also certify that you are not subject to backup withholding and that you are a US person.

The four most common W-9 mistakes:

• Wrong tax classification (most often LLC owners checking individual instead of the LLC's tax class)
• A wrong or mistyped TIN, which triggers a TIN matching failure with the IRS
• Forgetting the disregarded-entity naming rule, which puts the owner's name on line 1, not the LLC's
• Signing the backup withholding certification when it is not actually true for you

A correctly signed W-9 covers the requester's reporting needs until the underlying information changes.

How to fill out the W-8 series correctly

The W-8 family has more moving parts than the W-9 because it covers treaty claims, FATCA classification, and beneficial ownership in addition to identity.

As a general rule, W-8BEN and W-8BEN-E remain valid through the end of the third succeeding calendar year unless circumstances change. So a W-8BEN signed in 2026 is generally good through December 31, 2029.

What you usually enter is the same across most W-8s:

• Legal name
• Country of citizenship or country of organization
• Permanent residence address (not a PO box, not a US in-care-of address)
• Foreign TIN
• Type of US-source income covered

What changes the answer is everything fact-specific:

• Residency – a change in tax residency invalidates the form
• Beneficial owner status – especially when payments flow through intermediaries
• Entity classification under Chapter 4 (FATCA) – the right status box drives the withholding outcome
• Treaty claims – need an accurate country and treaty article on the form

A treaty claim with the wrong country or article triggers backup documentation requests at best and full 30% withholding at worst, so accuracy here is not optional.

How long do W-8 and W-9 forms stay valid?

The shortest answer: W-9 vs W-8 validity rules are different by design. Form W-9 has no fixed expiration, while most W-8 forms expire on a defined timeline.

For US persons, Form W-9 stays valid as long as the information on it remains correct. For foreign persons, Form W-8BEN and W-8BEN-E generally stay valid through the last day of the third succeeding calendar year, but some certifications remain valid indefinitely until a change in circumstances occurs.

Quick example: a Form W-8BEN signed in March 2026 generally remains valid through December 31, 2029, unless a change in circumstances makes it inaccurate before then.

A form on file but expired is treated as no form at all. If the documentation is missing or no longer valid, the payer may have to apply the default withholding rules for that type of payment – 24% backup withholding on reportable Form W-9 payments and 30% withholding on certain US-source payments to foreign persons – until a valid form is received.

Do I send W-8 and W-9 to the IRS?

No. A W-8 or W-9 tax form goes to the requester – the bank, broker, US client, or platform – not to the IRS. The requester keeps the signed form on file and uses it to decide two things: how to classify your income and how much (if anything) to withhold.

Downstream reporting differs by form:

• A correctly signed W-9 typically supports a Form 1099 – 1099-NEC for contractor payments, 1099-INT for interest, 1099-DIV for dividends, 1099-MISC for rents and royalties.
• A correctly signed W-8 typically supports a Form 1042-S for US-source income paid to a foreign person.

So the form you sign is documentation; the form your payer files is the actual information return at the IRS. If your tax status changes – you move to the US, become a citizen, or your entity classification shifts – you sign a fresh form so the payer's reporting stays accurate.

In short, a W-8 or W-9 form is required for any US-source payment where the payer must determine withholding and information reporting treatment, which is why almost every US bank, broker, marketplace, and client asks for one before the first payment goes out.

What to do if a bank, client, or marketplace asks for a W-8 or W-9

A missing or wrong W-9 or W-8 form has two concrete costs: 24% backup withholding on a US person's reportable payments, and 30% NRA withholding on a foreign person's US-source FDAP income. Both are recoverable later, but recovery means months of paperwork and a year-end reconciliation problem.

The fix is a 3-step process at onboarding: confirm your US tax status, complete the right form, and submit it before the first payment.

1. Figure out your US tax status

Form choice follows status, not address. For non-citizens, two IRS tests decide whether you are a US person.

Green card test: Holding a lawful permanent resident card at any point during the calendar year makes you a resident alien and a US person for tax purposes.

Substantial presence test: Physical presence of at least 31 days in the current year and 183 weighted days across the current and two prior years (100% of current-year days + 1/3 of prior-year days + 1/6 of days from two years prior) makes you a resident alien.

Resident alien example: A German engineer on an H-1B in San Francisco for two full calendar years passes substantial presence, and signs Form W-9 for every US payer.

Nonresident alien example: A foreign contractor invoicing a US company from abroad in São Paulo, who never enters the US, signs Form W-8BEN.

The decision tree, once the status is set:

• US citizen, green card holder, or resident alien (substantial presence) → W-9
• Foreign individual with US-source income → W-8BEN
• Foreign entity with US-source income → W-8BEN-E
• Foreign person with income effectively connected to a US trade or business → W-8ECI

2. Complete the form accurately

Wrong fields produce three concrete consequences: wrong withholding rate on every payment, wrong information return at year-end (1099 vs 1042-S mismatch), and follow-up documentation requests that can pause payouts until resolved.

The fields that get people in trouble:

• TIN mismatch – SSN for US individuals, EIN for US entities, ITIN or foreign TIN for non-US persons. Disregarded entities use the owner's name and TIN, not the entity's.
• Treaty country and article on W-8BEN / W-8BEN-E – a wrong article means full 30% withholding plus a re-certification request, not a partial rate.
• Chapter 4 / FATCA classification on W-8BEN-E – the FATCA status selected must match the entity's actual classification.
• Beneficial owner certification – sign only if you are the beneficial owner of the income, not an intermediary.

3. Submit the form on time

Delay has different consequences depending on which form is missing.

• Missing W-9 (US person): the payer applies 24% backup withholding on reportable payments such as 1099-NEC contractor income, 1099-INT interest, and 1099-DIV dividends.
• Missing W-8 (foreign person): the payer applies 30% withholding on US-source FDAP income, with no treaty rate available until valid documentation is on file.
• Account-level effects: banks may pause new account activity until certification is received; freelance marketplaces and payment processors apply their own platform rules, which vary by provider and are not IRS requirements.
• Year-end cleanup: a missing or wrong form usually means a corrected information return and a reconciliation problem on the signer's personal or entity tax return.

Quick reference: which form for which scenario

For fast lookup once you know your status, here is how the most common situations map to a form.

A clean form filed before the first payment is dramatically simpler than recovering over-withheld tax later. For freelancers and independent contractors filing US taxes from abroad, W-8 and W-9 forms compliance across multiple US payers comes down to one thing: getting the form right at onboarding is the highest-leverage move you can make.

Bottom line: W-9 for US persons, W-8 for foreign persons

The whole W-8 vs. W-9 question collapses into one rule once the framing is right: it comes down to US tax status, not your address.

• US person (citizen, green card holder, resident alien, domestic entity) → Form W-9
• Foreign person → the right W-8 subtype: W-8BEN for individuals, W-8BEN-E for entities, W-8ECI for foreign persons with effectively connected income, W-8EXP for foreign governments and exempt entities, W-8IMY for intermediaries
• When in doubt → confirm your US tax status before signing, since the wrong form costs time and money to undo

The W-9 vs W-8 ECI call is the one that trips people up most: if you are a US person, you sign a W-9 even when the income is effectively connected; W-8ECI is only for foreign persons whose income is connected to a US trade or business.

If you are dealing with cross-border income and want a sanity check before signing, our team of tax experts handles W-9 and W-8 form requirements for US companies every day, helping expats and foreign business owners pick the right form before the first payment.

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