If you have taken a sponsored job in the United States, or you are working toward one from abroad, the question of how to invest sits awkwardly between two sets of rules. Guidance written for Americans assumes you have a Social Security Number and pay US tax on everything. Guidance written for overseas investors assumes you live overseas. Neither quite describes someone on an H-1B in Seattle or an F-1 in Boston.
The thing that decides your position is not your passport. It is whether the IRS counts you as a resident alien or a non-resident alien, and that turns on a day count that most people have never heard of. Everything else — which broker will take you, which form you file, whether your gains are taxed — follows from that one classification.
Who this is for
- People who have relocated to the US on a sponsored work visa and want to start investing
- F-1 and J-1 students and recent graduates on OPT working out their tax status
- Candidates still abroad who want US market exposure before they move
- Sponsored employees holding RSUs or stock options who need to understand what the shares attract
- Anyone whose tax residency is about to change, in either direction
- Workers from treaty countries paying more withholding than the treaty actually requires
The document checklist below overlaps heavily with opening a US bank account or applying for an ITIN, so paperwork gathered for one generally serves the others.
Quick answer
Your visa and your days in the US decide whether you are a resident or non-resident alien. Non-residents file Form W-8BEN, pay 30% on dividends unless a treaty reduces it, and generally pay no US tax on listed-security gains. Residents file Form W-9 and are taxed broadly like US citizens. Interactive Brokers has the widest country coverage for non-residents; Charles Schwab International has no account minimum; Firstrade accepts international clients without a Social Security Number. Establish your status before you open anything, because the wrong form costs you either money or a correction.
First: resident or non-resident?
The Substantial Presence Test is arithmetic. You are treated as a US resident for tax if:
- you were in the US for 31 days or more in the current calendar year, and
- the weighted three-year count reaches 183 days — every day this year, plus one third of last year's days, plus one sixth of the days from the year before
Someone on an H-1B who moved in January and stayed will clear that easily in year one. They are a resident alien, file a W-9, and are taxed on worldwide income much like a citizen. Counter-intuitively this makes brokerage life simpler, not harder — ordinary accounts, ordinary forms.
Students and researchers are the exception
The exemptions here are frequently reported wrongly, and the two categories differ:
- Students on F, J, M and Q visas are exempt individuals, and remain exempt until they have been exempt for any part of more than five calendar years. "Any part of" is doing real work in that sentence — land on 20 December and that calendar year is spent.
- Teachers, trainees and researchers on J and Q visas work to a different and much shorter clock: the exemption goes once they have been exempt during any part of two of the six calendar years before this one. There is a limited way to stretch it, available only where a foreign employer has paid every penny of your compensation.
Either way you file Form 8843 to claim it. An F-1 student in year three is a non-resident alien living in Ohio — a combination that confuses both brokers and tax software.
Why this matters before you open an account
Filing a W-8BEN when you are actually a resident alien means your broker withholds 30% on dividends you should be taxed on normally, and misreports you to the IRS. Filing a W-9 when you are a non-resident means no treaty benefit and the wrong return. Neither is catastrophic but both take longer to unwind than to get right.
Who will accept you
If you have no US tax number yet, Firstrade is the one that says so plainly — its international account does not require a Social Security Number or tax ID. The catch is its country list, covered below, and the UK is not on it.
If you want the widest chance of being accepted at all, Interactive Brokers. It onboards through locally regulated subsidiaries rather than one US entity, which is why its reach is broader than anyone else's.
If you already have US ties — family there, a previous stint, an employer relationship — Charles Schwab International is built for exactly that, and the account minimum is now zero.
If you trade options, tastytrade accepts individuals from a shortlist of countries, but supports no international entity accounts whatsoever.
Webull publishes nothing about residency eligibility. Treat it as unknown rather than available.
Two corrections to the lists you will find elsewhere. TD Ameritrade is simply not an option any more — the final clients moved onto Schwab's platform in May 2024, and the broker-dealer registrations with the SEC and FINRA were withdrawn by that December. thinkorswim belongs to Schwab now. And Firstrade, which appears on nearly every "best for non-residents" roundup, does not list the United Kingdom among its supported regions.
If you are already physically in the US and count as a resident alien, this table stops being the relevant one — you can use essentially any US broker on ordinary terms.
What decides eligibility
Where you live, more than where you are from:
- Country of residence, which is the primary filter
- OFAC sanctions or FATF high-risk listing, which rules you out with any US-regulated broker regardless
- Visa status if you are in the US
- Whether you can produce a US address, US bank account or ITIN for certain account types
- The broker's own unpublished risk policy
Brokers exclude whole regions without explanation. Check the list before you invest effort in an application.
Documents
- Passport, colour scan of photo and signature pages
- National ID where requested
- Proof of address from the last 90 days — utility bill, bank statement, government letter
- Form W-8BEN if non-resident, or Form W-9 if resident
- ITIN for some brokers and account types
- Home-country tax identification number
- Employment details, which for sponsored workers usually means your offer letter or visa documentation
- Sometimes a US bank account for funding
Form W-8BEN is the one that determines your withholding. It certifies non-US status and is the only place a treaty claim can be made. Opening through a company rather than personally means Form W-8BEN-E instead.
The tax, in practical terms
Dividends
US-source dividends paid to a non-resident alien are taxed at a flat 30%, withheld before the money reaches you, with no deductions allowed against it.
A treaty may cut that, commonly to 15%. The US has treaties with roughly 68 jurisdictions, and three are not in their usual state: Hungary's treaty has been terminated, and those with Russia and Belarus are partially suspended. If your origin country is one of those three, older guidance will mislead you. Check the IRS Treaties A to Z page directly.
The lower rate is not applied for you. You claim it in Part II of the W-8BEN, naming your country of residence and the treaty article. Blank means 30%.
Capital gains
Gains on US-listed shares and bonds not connected with a US trade or business are generally outside US tax for non-residents. Three exceptions matter, and the first one is the trap for people working in the US:
- 183 days or more of physical presence during the tax year. US-source capital gains then face a flat 30%. The IRS states explicitly that this count is unrelated to the Substantial Presence Test — it is a separate test within a single year. An F-1 student in year four is a non-resident alien who may well have been in the US for more than 183 days, and the two facts sit together uncomfortably. This is worth specific advice.
- Gains effectively connected with a US trade or business, taxed as business income.
- US real property, which FIRPTA pulls in. The withholding is 15%, and it bites on what the property sells for rather than on what you made — so a sale at a loss still has tax withheld from it. Sales at or under US$300,000 where the buyer intends to live there are carved out.
ITIN
Needed by some brokers, and needed by you if you want to file a return to reclaim over-withheld tax. Apply on Form W-7 with certified documents. Current IRS guidance is about 7 weeks, or 9 to 11 weeks in filing season or from abroad.
If your employer gives you shares
This is the part that is specific to sponsored employment and gets skipped in general investing guides.
RSUs and options that vest while you are working in the United States are compensation, not investment income. They run through payroll and are taxed accordingly, whatever your residency status. That is a different question from how the shares behave once you simply hold them, where ordinary dividend withholding and capital gains rules apply.
The genuinely difficult case is equity that was granted in one tax residency and vests in another — granted while you were abroad, vesting after you moved, or the reverse when you leave. Several countries will each claim a slice, and the sourcing rules are not intuitive. If you hold meaningful equity across a residency change, one session with a cross-border adviser is money well spent. This is not a situation to resolve from forum posts.
The brokers
Interactive Brokers
The reach is wide for a structural reason rather than a commercial one. Instead of serving everyone from a single American entity, IBKR holds licences in each major market and onboards you through whichever one covers where you live — the FCA if you are in Britain, the Central Bank of Ireland across much of the EU, CIRO in Canada, ASIC in Australia, the SFC in Hong Kong, SEBI in India, with separate arms in Japan and Singapore. The practical effect is that your account answers to a regulator you can actually reach.
No minimum on cash accounts, multi-currency support that matters if you are earning in one currency and investing in another, and tax reporting detailed enough to check withholding against your W-8BEN. The interface is heavy; IBKR Global Trader is the simplified route to the same account.
Charles Schwab International
Schwab One International is built for clients outside the US, and the minimum is now US$0 — worth stating because the old US$25,000 figure is still quoted widely. Covers US equities, ETFs, mutual funds and fixed income.
Good fit if you have US ties already: family, a prior period of residence, or an employer relationship. Country eligibility gets resolved during the application rather than published cleanly.
Firstrade
States directly that you can open an international account without being a US citizen or permanent resident and without a Social Security Number or tax ID — which removes the usual blocker for someone who has not yet got an ITIN. Commission-free on stocks and ETFs.
The constraint is the country list: China, Hong Kong, India, Israel, Japan, South Korea, Macau, Malaysia, Mexico, New Zealand, Singapore and Taiwan among those published. Not the UK.
tastytrade
Options-focused, accepts individuals from selected countries, and explicitly does not support international entity accounts. Individual margin, individual cash and joint only. The country list changes.
Webull
No published eligibility statement on residency, SSN requirements or supported countries — not on the site, the help centre or the terms. Its US broker-dealer is Webull Financial LLC and non-US markets appear to be served by separate local entities, which would imply the US entity is not the non-resident route, but that is inference rather than a published policy. Ask them directly.
Opening it, in order
- Settle your residency status with a cross-border adviser, using your visa type and actual days in the US. Everything downstream depends on this.
- Apply for an ITIN if required. Two months is a realistic allowance.
- Gather documents — passport, proof of address, home tax number.
- Complete the right form. W-8BEN with Part II if you are non-resident and a treaty applies; W-9 if you are resident.
- Confirm the broker serves your country before submitting.
- Submit and expect anywhere from days to several weeks.
- Fund by wire, or ACH once you have a US bank account.
- Verify the withholding rate on the live account. If you claimed 15% and it shows 30%, the form did not land. Almost nobody checks this and it is the cheapest error to catch early.
Funding, and the currency question
- Wires attract fees at both ends and often from an intermediary bank
- The exchange rate spread usually costs more than the wire fee on anything above a few thousand
- Some brokers accept dollars only; others hold multiple currencies, which is genuinely useful if your salary and your investments are in different ones
- Specialist transfer services often beat bank rates on major corridors, though not all will send to a brokerage
- Check your home country's outbound currency rules, which still apply to you while you are abroad
Mistakes worth avoiding
Filing the wrong form for your status. The commonest error among sponsored workers: using a W-8BEN while actually being a resident alien, because the guidance you found was written for people living overseas.
Leaving the treaty box blank. The gap between 30% and 15% compounds over every dividend for years.
Relying on a treaty that has changed. Hungary terminated; Russia and Belarus partially suspended.
Assuming gains are unconditionally untaxed. The 183-day presence rule catches people who are non-resident on paper but physically in the US most of the year — which describes a lot of students.
Not updating the broker when your status changes. Getting a green card or crossing the Substantial Presence threshold means a new form within 30 days of the change.
Forgetting your home country. Most countries tax residents on worldwide income. US-exempt is not tax-exempt.
Letting the W-8BEN lapse. It expires on the last day of the third calendar year after signing.
Treating equity compensation as an investing question. It is a payroll and sourcing question first.
If a US account is not available to you
- A home-country broker with US market access through international routing
- Irish-domiciled ETFs tracking US indices — often better after tax for non-US investors than US-domiciled equivalents, because of how fund-level withholding interacts with the treaty
- US-domiciled ETFs cross-listed in London, Amsterdam or Frankfurt, remembering that domicile rather than listing venue usually drives the tax
- Your employer's share plan, if you have one, which sidesteps the account-opening question entirely for that holding
The ETF domicile point is the one most people miss and the one with the largest long-run effect. Worth an hour of advice before committing capital.
Disclaimer
General educational information only. Not financial, tax, legal or immigration advice. Visa categories, treaty status, broker eligibility and withholding rates all change. Confirm your own position with the broker, a licensed cross-border tax adviser, and where visa status is involved, an immigration attorney.
The short version
Work out whether you are a resident or non-resident alien before anything else — your visa type and your day count decide it, and the answer changes which form you file and whether your gains are taxed at all. Then pick a broker that serves your country, complete the right form including any treaty claim, and check the withholding rate the account actually ends up on.
If you hold employer equity across a change of tax residency, deal with that separately and with advice. It is the part of this that most reliably costs people real money.