Tax-Trigger Events for US Expats: Selling US Assets, Inheritance & Stock Options
Selling US property, vesting RSUs, inheriting assets, or renouncing citizenship: each creates US tax obligations that sit outside your normal annual return. RSU income isn't FEIE-eligible. The §121 exclusion erodes after years abroad. Here's what each event actually triggers.
Most US expats who file taxes annually assume their regular return handles everything. These four events break that assumption.
Selling US property, receiving an inheritance, vesting stock options or RSUs, and renouncing citizenship each create US tax obligations that sit outside the normal filing rhythm. They come with their own forms, their own deadlines, and in some cases their own planning windows that close before the event itself.
The connecting thread is citizenship-based taxation. The US taxes its citizens on worldwide income regardless of where they live. These events are taxable by the US whether you have been abroad for one year or twenty, whether the assets are held in the US or overseas, and whether your foreign country taxes them too.
This guide covers what each event actually triggers and what to do about it.
Four events create outsized US tax complexity for expats beyond the normal annual return. Selling US property: capital gains apply, the Section 121 primary residence exclusion erodes after years abroad, and state source income rules mean the property state can tax the gain even if you changed domicile long ago. Receiving a US inheritance: no federal income tax on what you receive, but Form 3520 reporting applies if the estate is administered outside the US and the amount exceeds $100,000, with penalties up to 25% of the amount received for non-filing. Stock options and RSUs: RSU vesting income is taxed as ordinary income at vest and is not eligible for the Foreign Earned Income Exclusion under IRS Revenue Ruling 2004-4. Employer withholding at the 22% flat rate almost always falls short of the actual liability. Renouncing citizenship or relinquishing a long-term Green Card may trigger the exit tax under IRC Section 877A if covered expatriate thresholds are met. The planning window before each event matters more than the filing after it.
What makes a tax-trigger event different from normal expat tax filing
Most expats who file annually deal with the same income streams each year: salary, freelance income, investment income. The annual return becomes familiar. These events are different because they are one-time or irregular transactions that create new, separate obligations on top of the regular return.
Three reasons these events catch people off guard. First, the timing is unpredictable. A property sale, an inheritance, or an equity vest may not align with the normal tax planning calendar.
Second, the obligations often include forms that never appear on a standard expat return: Form 3520, Form 4797, Form 8288, or quarterly estimated tax payments. Third, the US taxes these events regardless of how long you have been abroad, which country the assets are in, or whether the foreign country also taxes the same event.
The most important insight: every event in this article has a planning window before it occurs. During that window, choices about timing, basis documentation, and structure can materially change the tax outcome. After the event, the only question is how much is owed.
| Event | Key U.S. Tax Trigger | Primary Forms | FEIE Helps? | Most Important Thing to Know |
|---|---|---|---|---|
| Selling U.S. real estate | Capital gains above cost basis | Schedule D, Form 8949, Form 4797 (if rented) | No | §121 exclusion may shrink after years abroad, and depreciation recapture is always taxable. |
| Selling U.S. investments | Short- or long-term capital gains | Schedule D, Form 8949 | No | Foreign mutual funds may trigger PFIC reporting and higher tax. |
| Receiving a U.S. inheritance | Generally no income tax; stepped-up basis | Form 3520 (if required) | N/A | Missing Form 3520 can result in penalties of up to 25% of the amount received. |
| RSU vesting | Ordinary income at vesting | W-2, Form 1116 | No | Employer withholding (22%) is often lower than the final tax owed. |
| NSO exercise | Ordinary income on the spread | W-2, Form 1116 | No | Income sourcing rules can apply if the grant predates your move abroad. |
| ISO exercise | Potential AMT liability | Form 6251, Form 3921 | No | Foreign taxation may occur before U.S. tax is due, creating timing mismatches. |
| Renouncing citizenship or long-term Green Card | Exit tax for covered expatriates | Form 8854, final Form 1040 | No | Not filing Form 8854 can make you a covered expatriate regardless of net worth. |
Selling US assets
Real estate
Selling US property while living abroad triggers federal capital gains tax. The seller is a US citizen, so the standard rules apply: short-term gains (property held under one year) are taxed as ordinary income, long-term gains at 0%, 15%, or 20% depending on taxable income, plus 3.8% Net Investment Income Tax above certain thresholds.
The Section 121 primary residence exclusion can eliminate up to $250,000 of gain for single filers or $500,000 for married filing jointly. But there is a catch for expats. The exclusion requires 2 years of actual use as a primary residence within the last 5 years. Time spent living abroad does not count toward the use requirement. An expat who has been gone for 4 or more years likely no longer qualifies for the full exclusion. A partial exclusion may be available if the sale was due to a work-related move, but this is fact-specific.
Depreciation recapture is the item most expats miss. If the property was rented at any point and depreciation was claimed or should have been claimed, that amount is recaptured as ordinary income at rates up to 25% when the property is sold. The Section 121 exclusion does not cover depreciation recapture.
State source income is the other overlooked obligation. Selling a California or New York property while domiciled in Florida still triggers state income tax in the property's state. State taxes follow where the property is located, not where the seller lives.
One common misconception: US citizens abroad are not subject to FIRPTA withholding. FIRPTA applies to foreign persons, not US citizens. Buyers do not need to withhold from the sale proceeds when the seller is a US citizen, regardless of where the seller lives.
Full guide: Selling US real estate as an expat
Investment accounts
Capital gains on US brokerage accounts are taxed at the standard short-term or long-term rates. The Foreign Tax Credit on Form 1116 may offset US liability if the foreign country also taxed the same gain.
If investment accounts are held in a foreign brokerage rather than a US one, PFIC rules may apply to any foreign mutual funds or ETFs in the account. PFIC treatment is complex and can produce unexpectedly high effective tax rates.
Receiving a US inheritance while living abroad
The first thing to understand: there is no federal inheritance tax paid by the heir. The estate pays federal estate tax above the $15 million exemption (2026). You as the heir pay no US income tax on what you receive. The inheritance is not reported as income on Form 1040.
The most valuable immediate benefit is the stepped-up basis. Inherited property resets its cost basis to fair market value at the date of death. If your parent bought a house for $150,000 in 1990 and it is worth $900,000 at death, your basis is $900,000. If you sell it the following year at $920,000, you owe capital gains tax only on $20,000 of gain. Document the date-of-death value of every inherited asset immediately: appraisals for real property, broker statements for investment accounts, bank balances. This documentation is essential when you eventually sell.
The reporting trap most people miss is Form 3520. This form is required if you receive more than $100,000 from a foreign person or foreign estate in a single tax year. The threshold applies when the estate is administered outside the US, which covers US citizen parents who lived and died abroad. Form 3520 is an information return, not a tax bill. But the penalty for non-filing is up to 25% of the amount received. A $400,000 inheritance triggers a potential $100,000 penalty if the form is not filed.
FBAR and Form 8938 (FATCA) may also apply if inherited assets include foreign financial accounts whose balances push you above the respective thresholds: $10,000 aggregate for FBAR, $200,000 at year-end or $300,000 at any point during the year for Form 8938 for expats living abroad.
Six US states impose inheritance taxes on heirs depending on where the deceased was domiciled and the relationship between heir and deceased. Twelve states plus DC impose estate taxes at exemptions far below the federal $15 million.
Full guide: Inheriting US assets while living abroad · FBAR for American expats
Stock options and RSUs: the equity compensation trap
This is the event that most often results in an unexpected, large tax bill for expats who thought their FEIE covered everything. It does not.
RSUs: ordinary income at vest, not FEIE-eligible
RSUs vest over time. At each vest date, shares are delivered to the employee and the fair market value of those shares on the vest date is taxable as ordinary compensation income. It appears on your W-2. It is taxed at ordinary income rates up to 37% federally.
The point most expats do not know until it is too late: the FEIE does not apply to RSU vesting income. IRS Revenue Ruling 2004-4 explicitly excludes RSU income from the definition of "foreign earned income." An expat who qualifies for the FEIE and successfully excludes salary income cannot exclude RSU vest income. It is fully taxable by the US regardless of where you lived or worked when the shares vested.
The Foreign Tax Credit on Form 1116 may apply if the foreign country also taxed the vest income. This is the primary relief mechanism for RSU double taxation abroad.
After the vest date, shares held for more than 1 year from the vest date qualify for long-term capital gains rates when sold. Shares sold within 1 year of vesting are short-term gains taxed at ordinary income rates.
Source income allocation for pre-move grants
If RSUs or options were granted while you worked in the US and vest while you work abroad, the income is split between US-source and foreign-source based on the proportion of days worked in each location during the grant-to-vest period.
The US-source portion is always taxable without FEIE offset. The foreign-source portion may generate a Foreign Tax Credit if the foreign country taxed it.
An illustrative example using round numbers: RSUs granted over a 2-year vest period, with the employee spending half that time working in the US and half abroad. Roughly half the vest income is US-source and fully taxable. Half is foreign-source and eligible for FTC offset if foreign taxes were paid. Multi-country situations across three or more tax years quickly become complex enough to require professional help.
NSOs and ISOs
Non-Qualified Stock Options trigger ordinary income tax at the moment of exercise. The spread between the exercise price and the fair market value at exercise is W-2 income, taxed at marginal rates. The same source allocation rules apply if the options were granted before the move abroad.
Incentive Stock Options are not subject to regular income tax at exercise. However, the spread at exercise may trigger Alternative Minimum Tax. If shares are held at least 2 years from the grant date and 1 year from the exercise date, the eventual gain receives long-term capital gains treatment. A sale before those holding periods are met results in ordinary income treatment.
Foreign countries often do not recognize the US ISO deferral. Many treat the spread at exercise as taxable ordinary income in the year of exercise, creating a mismatch: foreign tax is due now, US tax is due later on a different event. This timing difference requires careful tracking to claim FTC correctly.
The withholding gap
Employers withhold federal tax on RSU vest income at a flat 22% supplemental rate. For employees in the 32% or 37% bracket, the gap between the 22% withholding and the actual rate due at filing is not apparent until tax season. Combined with the loss of FEIE on this income, the underpayment can be substantial.
The solution is quarterly estimated tax payments using Form 1040-ES. Calculate the expected vested income for the year based on the vesting schedule and an estimated share price, apply your actual marginal rate, and pay quarterly to avoid underpayment penalties.
If vested RSU shares are held in a foreign brokerage account, the account balance may trigger FBAR reporting if it exceeds $10,000 aggregate at any point during the year, or Form 8938 (FATCA) if it exceeds the applicable thresholds for expats.
Renouncing citizenship or relinquishing a Green Card
Formally renouncing US citizenship or relinquishing a long-term Green Card (held for 8 of the last 15 years) may trigger the exit tax under IRC Section 877A.
The exit tax applies only to covered expatriates: those who meet at least one of three tests. Net worth of $2 million or more at the time of expatriation. Average annual US net income tax liability above $211,000 over the five preceding years (2026 figure). Failure to certify five years of tax compliance on Form 8854.
The certification test is the one people miss. Failing to file Form 8854, or filing it incorrectly, triggers covered expatriate status automatically regardless of net worth or income. Even an expat well below both financial thresholds becomes a covered expatriate if the certification is absent.
For covered expatriates, the mechanism is a deemed sale of all worldwide assets at fair market value the day before expatriation. Gains above the $910,000 exclusion (2026) are taxed at capital gains rates. Deferred compensation, retirement accounts, and trust distributions each follow different rules under the same regime.
Most expats who renounce are not covered expatriates and owe no exit tax. The filing obligation still applies.
What these events have in common: plan before, not after
Each event in this article rewards planning before it happens and punishes discovery after.
For property sales: document your cost basis and improvement records now, track the Section 121 use clock, and model the tax before accepting an offer.
For inheritance: assemble date-of-death valuations immediately and calendar the Form 3520 deadline alongside your regular return.
For equity compensation: know your vesting schedule, understand that FEIE will not reduce the vest income, set up estimated tax payments before the vest dates, and track source allocation if your grant predates your move.
For potential expatriation: run the three covered expatriate tests before the renunciation appointment, not after. The covered status determination and the Form 8854 certification must be in order before the event is finalized.
The common mistake across all four is the same: learning about the tax obligation after the event, at which point the question is only how much is owed rather than whether it can be reduced.
Frequently asked questions
Does the FEIE apply to RSU income?
No. IRS Revenue Ruling 2004-4 explicitly excludes RSU income from the definition of foreign earned income. RSU vesting income is taxable as ordinary income regardless of FEIE eligibility. The Foreign Tax Credit may offset some of the liability if the foreign country also taxed the same income. Foreign Earned Income Exclusion
Do I owe US tax when I inherit from a US estate while living abroad?
No federal income tax on the inheritance itself, and no federal inheritance tax unless the estate exceeds $15 million (2026). Form 3520 reporting is required if the estate is administered outside the US and the amount exceeds $100,000. State inheritance taxes may apply depending on the deceased's domicile. Inheriting US assets while living abroad
Does the Section 121 exclusion still apply after living abroad for several years?
Possibly not the full exclusion. The 2-of-5-year use test requires actual residential use of the property, and time spent abroad does not count. An expat 4 or more years out may not qualify for the full exclusion. A partial exclusion may be available if the move was work-related. Selling US real estate as an expat
What triggers the exit tax?
Meeting any one of three tests: net worth $2 million or more, average annual tax liability above $211,000 (2026), or failing to certify five years of tax compliance on Form 8854. Most expats who renounce are not covered expatriates. US exit tax guide
I vest RSUs in multiple countries. How is the income allocated?
Based on the ratio of days worked in each location during the grant-to-vest period. The US-source portion is taxable without FEIE offset. Foreign-source portions may generate Foreign Tax Credits if taxed in those countries. Multi-country allocations are complex and benefit from professional preparation.
Do these events affect my FBAR or FATCA obligations?
Potentially yes. Inherited foreign financial accounts, RSU shares held in foreign brokerage accounts, and sale proceeds deposited into foreign accounts may push balances above FBAR ($10,000 aggregate) or FATCA ($200,000 year-end / $300,000 at any point for expats) thresholds. FBAR for American expats
Get professional guidance before the event
These events have one thing in common: the best time to plan is before the transaction closes, the shares vest, or the renunciation appointment is scheduled. SavvyNomad's CPA-access service connects you with cross-border tax professionals who work with expats on exactly these situations.
