Selling Your US Home After Moving to France: Capital Gains, the Section 121 Exclusion, and What to Report

Selling your US home after moving to France involves two tax systems, two different capital gains frameworks, two reporting forms, and a timing question that can be worth tens of thousands of dollars. The US side is driven by the Section 121 principal residence exclusion and the rules for how long you have to sell before the exclusion phases out. The French side requires you to declare the sale on your French income tax return and apply the treaty credit mechanism to avoid double taxation. Neither system is impossible to navigate, but failing to understand how they interact, and in particular how long you can wait to sell before the Section 121 exclusion becomes unavailable, produces tax outcomes that could have been avoided with earlier planning. This article is for informational purposes only and does not constitute tax or legal advice. Tax rules are complex and change frequently: consult a qualified cross-border tax professional before making any filing or planning decisions.

The Section 121 Exclusion: What It Is and Why Timing Matters

Section 121 of the Internal Revenue Code allows US homeowners to exclude from taxable income up to $250,000 of capital gain from the sale of a principal residence ($500,000 for married couples filing jointly), provided they meet the ownership and use tests.

The ownership and use tests require that the seller owned the home for at least two years and used it as their principal residence for at least two of the five years immediately preceding the date of sale. The two years of use do not need to be continuous: they can be any 24 months within the five-year lookback window, including periods of temporary absence.

For Americans who have moved to France, the most important consequence of the five-year lookback window is this: you have approximately three years from the date you stop living in the home as your principal residence before the Section 121 exclusion becomes unavailable. After three years away, even if you owned the home for decades, you will not have met the two-year use test within the prior five years, and the full capital gain on the sale becomes taxable.

This three-year window is the most financially significant planning deadline for American homeowners who move to France and do not immediately sell their US property. If you moved to France in September 2024 and last used your home as your principal residence in September 2024, you must complete the sale by approximately September 2027 to preserve the Section 121 exclusion. Waiting until 2028 forfeits the exclusion entirely.

The gain excluded under Section 121 is not reported on Form 8949 or Schedule D if it is fully within the exclusion limit, unless you receive a Form 1099-S, in which case you must report the sale even if the gain is excludable. Gain above the exclusion is reported and taxed as capital gains income in the year of sale. Long-term capital gains rates (for homes held more than one year) are 0%, 15%, or 20% depending on your taxable income and filing status, plus the 3.8% Net Investment Income Tax (NIIT) for higher earners.

In our experience, the Americans who lose the Section 121 exclusion most often are those who moved to France, intended to return to the US within a few years, kept the home in case plans changed, and then found themselves still in France in year four or five with a home they had always planned to sell. The three-year clock passes faster than it feels. Start tracking it from the day you leave the home as your primary residence, not from the date your visa was issued or the date you arrived in France.

How the Exclusion Applies When You Are a French Tax Resident

Being a French tax resident does not alter the US-side Section 121 calculation. The exclusion is a provision of the US Internal Revenue Code and applies based on your US tax filing status and your history of ownership and use of the property. You do not need to be living in the US at the time of sale. You need to have met the two-of-five-year use test within the lookback window.

What French residency does change is the French tax picture, discussed separately below. The US calculation for the Section 121 exclusion proceeds as it would for any US person regardless of where you live when you sell.

One practical note: if you lived in the home before moving to France and are selling it while living in France, you will not meet the IRS definition of “non-resident alien” for withholding purposes. As a US citizen, you are always a “US person” for IRS purposes. The Foreign Investment in Real Property Tax Act (FIRPTA) withholding requirements that apply to foreign nationals selling US real estate do not apply to US citizens. However, if any title company, escrow agent, or buyer’s attorney asks about FIRPTA status, clarify clearly that you are a US citizen, which exempts the transaction from FIRPTA withholding.

Calculating the Capital Gain on Your US Home

The capital gain is the difference between your adjusted basis in the property and the amount realized from the sale.

Your adjusted basis starts with the original purchase price and is adjusted upward for capital improvements you made (additions, renovations, major systems replacements) and adjusted downward for any depreciation you claimed if the property was ever used for rental income. If you ever rented the home, even briefly, the portion of the gain attributable to prior depreciation deductions is treated as unrecaptured section 1250 gain and taxed at a maximum 25% federal rate, outside the Section 121 exclusion. This depreciation recapture is separate from the capital gain calculation and is not excluded by Section 121.

The amount realized is the net proceeds of the sale: the sale price minus selling costs (real estate agent commissions, transfer taxes, legal fees, and closing costs directly related to the sale). These selling costs reduce the gain dollar for dollar.

The net capital gain, after the Section 121 exclusion if applicable, is reported on Form 8949 (Sales and Other Dispositions of Capital Assets) and carried to Schedule D of your Form 1040. The gain is classified as long-term if the property was held more than one year from purchase to sale. For most Americans who have owned their homes for many years, long-term capital gains treatment applies. The IRS publishes detailed guidance on home sale capital gains in Publication 523, which covers the Section 121 exclusion, the use and ownership tests, and reporting requirements. Instructions for Form 8949 cover how to report the sale proceeds and basis on the capital gains schedule.

The Net Investment Income Tax (NIIT) of 3.8% applies to the gain above the Section 121 exclusion if your modified adjusted gross income exceeds $200,000 (single) or $250,000 (married filing jointly). Gains within the Section 121 exclusion are not subject to the NIIT. Gains above the exclusion are.

Sources: IRS, Topic 701, sale of your home, IRS, Topic 409, capital gains, IRS, Topic 559, net investment income tax.

The French Tax Picture: What You Must Declare and How the Treaty Applies

If you are a French tax resident at the time you sell your US home, France considers you subject to French tax on your worldwide income, including capital gains from the sale of US real estate. The US-France tax treaty addresses this dual taxation through a credit mechanism.

Under the treaty, the United States retains taxing rights over gains from the sale of real property located in the United States. France also taxes its residents on worldwide income, including foreign real estate gains. The mechanism that prevents double taxation is a crédit d’impôt on the French return: for a gain on US real property the credit is equal to the tax paid in the United States on that gain, and it cannot exceed the French tax attributable to it.

In practical terms, this means: you declare the sale of the building on Form 2048-IMM, which you file with the service de la publicité foncière et de l’enregistrement of your tax office within the month that follows the sale, and the gain is taxed at the flat rate of 19 percent, plus prélèvements sociaux, when that form is filed. The gain is expressed in euros, and the exchange-rate method (rates at the dates of purchase and sale, or annual average rates) should be confirmed with your advisor. You apply the treaty credit. The net result is that you typically pay the higher of the two applicable rates on the total gain, but not the sum of both.

The French prélèvements sociaux (social contributions at approximately 17.2%) may apply to the capital gain above the Section 121 exclusion as received by a French resident. The application of prélèvements sociaux to US real estate gains for French residents may be subject to evolving positions, and the current treatment should be confirmed with a cross-border tax advisor. This layer is separate from income tax and can meaningfully increase the effective French tax on the gain.

For the gain that is within the Section 121 exclusion, the French tax treatment of the excluded portion is a substantive question. The Section 121 exclusion is a US domestic tax provision, and it is not certain that France recognizes it automatically. The treaty gives no credit for tax that was not paid in the United States. Under the treaty, the credit against French tax is equal to the tax paid in the United States on the gain, and it cannot exceed the French tax attributable to that gain, so a portion that Section 121 excludes carries no US tax and earns no credit. This is an area requiring professional guidance for any transaction involving meaningful excluded gains.

The treaty credit is the US tax paid, so the portion the US excludes earns no credit, and the social contributions layer is separate from income tax. Settle your position before the sale year closes, not at filing time.

Form 8949, Schedule D, and French Form 2048-IMM: The Reporting Requirements

On the US side, the sale is reported on Form 8949 and Schedule D of your Form 1040 for the tax year in which the sale closed. If the gain is fully within the Section 121 exclusion limit, you may not need to report the sale at all on Form 8949, provided you meet the full exclusion conditions. However, if any portion of the gain exceeds the exclusion, the excess is reported. If you received Form 1099-S (Proceeds from Real Estate Transactions) from the title company, the gross proceeds are already reported to the IRS, and you must file Form 8949 showing the basis and resulting gain or loss even if the net reportable gain is zero.

On the French side, the notice of Form 2047 states that the sale of a building is declared on Form 2048-IMM, within the month that follows the sale, and that the gain taxed at 19 percent is shown on line 3VZ of Form 2042 C to compute the reference tax income. The impots.gouv.fr page on selling a property abroad adds that the gain is also shown on Form 2047 (cadre 3). The amount is entered in euros using the exchange rates applicable to the cost basis and the sale proceeds. Where the gain was taxed at source abroad, the same notice states that a credit may be deducted from the French tax computed on these declarations, depending on the country and the treaty. The French tax administration’s guidance on how foreign income and gains are declared is published on impots.gouv.fr.

The sale of a US home does not generate a Form 3916 filing obligation in itself. Form 3916 is for foreign financial accounts (bank accounts, brokerage accounts, retirement accounts held at foreign financial institutions). A US property is not a financial account. FBAR and FATCA reporting for property sales is limited to the financial accounts through which sale proceeds flow, and the FBAR covers only accounts located outside the United States: proceeds deposited into a US bank account or brokerage account are not FBAR-reportable, while proceeds transferred to a French account, or to any other account outside the US, count toward the $10,000 aggregate that triggers the FBAR filing requirement. The obligation runs the other way in France, where your US accounts are the foreign ones and are declared on Form 3916 with your French return. For the US account reporting framework, see our guide on US account reporting obligations once you leave (FBAR, FATCA).

The sale year is when your return stops being simple: Form 8949 and Schedule D arrive alongside the 2555 or 1116 you already file, and the Section 121 exclusion has to be applied in the right place for the foreign tax credit to come out correctly. Expat filing software covers the standard sale. If the property was rented and depreciation recapture is in play, a plan that includes a tax professional review is the safer route than working it out alone.

Selling a Rented US Home: Additional Complexity

If you rented out your US home after moving to France, either as a deliberate investment decision or while waiting to sell, the tax picture has additional layers.

Rental income from the US property during the French residency period must be declared on both the US return (Schedule E) and the French return (the income is computed on Form 2044, then carried through cadre 4 of Form 2047) with the treaty credit applied. For how rental and passive income is treated on the French return, see our French income tax return guide.

More significantly, any depreciation deductions claimed against the rental income reduce your adjusted basis in the property. When you sell, the Section 121 exclusion does not cover the gain attributable to depreciation deductions: that portion is unrecaptured section 1250 gain on the US return, taxed at a maximum 25% federal rate, regardless of how long the home served as your principal residence. The recapture amount is calculated separately from the capital gain and is reported on Form 4797 as well as Schedule D.

If the home was rented for an extended period, the depreciation recapture can be substantial. For a home with an original allocated depreciable basis of $300,000 depreciated over five years, the accumulated depreciation would be approximately $54,500 ($300,000 divided by 27.5 years, times 5 years), all of which would be subject to recapture tax at the time of sale, completely outside the Section 121 exclusion.

Timing Strategy: When to Sell for the Best Combined Outcome

The timing of the sale is the most valuable planning lever for Americans in France who own a US home.

The Section 121 exclusion argument favors selling within three years of vacating the home as a principal residence. Beyond three years, the exclusion is unavailable and the full gain is taxable in the US, potentially at a meaningful rate for homes with large appreciation.

The French income tax argument is more nuanced. The notice of French Form 2047 states that real estate gains are taxed at the flat rate of 19 percent, plus prélèvements sociaux, when Form 2048-IMM is filed, so the French rate on the gain does not depend on your bracket or your other income in the year of sale. The French credit mechanism interacts with your US tax year results, so modeling the combined US-French outcome for the specific tax year of the sale, versus the following year, is worth doing when you have flexibility on closing date.

The NIIT threshold argument adds a further variable: if the gain above the Section 121 exclusion pushes your US MAGI above the NIIT thresholds, the additional 3.8% applies. Spreading income across years where possible, or claiming the exclusion while still within the window, reduces NIIT exposure.

No single “best” timing applies to everyone. The combination of the Section 121 three-year clock, the NIIT threshold, and any prélèvements sociaux exposure makes this a calculation that benefits from running specific numbers before deciding when to sell, rather than deferring the decision until the transaction is underway. Keeping the home instead raises a separate French question: the IFI, France’s real estate wealth tax.

Common Mistakes to Avoid

Missing the Section 121 three-year window is the costliest error, and it is irreversible. Once the window closes, the exclusion is gone. Americans who stay in France longer than originally planned and keep their US home as a backup are the most common group to lose the exclusion through inaction rather than intentional decision. Track the three-year window from the day you vacate the home as your principal residence and treat it as a hard deadline. Timing the sale against your residence date can change the outcome materially, and a consulting call before the transaction is worth far more than planning after it.

Assuming the Section 121 exclusion makes the sale entirely invisible to France is incorrect. The excluded portion on the US return may still require declaration on the French return and may still be subject to French tax depending on the treaty application and the prélèvements sociaux question. What we see most often is Americans assuming the French return does not require anything related to a US home sale because they received a Form 1099-S showing proceeds and filed a US return showing no taxable gain after the exclusion. The French obligation is independent of whether the US shows taxable income.

Forgetting depreciation recapture if the home was rented produces an unexpected US tax bill at sale time. Model the depreciation recapture separately from the capital gain before accepting an offer or planning the tax budget for the sale year.

Treating the sale proceeds as invisible for FBAR purposes once they leave the US is an error if the transfer pushes your non-US account balances above the FBAR reporting threshold ($10,000 aggregate at any point during the year). Proceeds that stay in a US bank or brokerage account are not FBAR-reportable, because the FBAR covers only financial accounts located outside the United States, but proceeds moved into a French account count toward that aggregate.

Not converting the US cost basis and sale proceeds to euros consistently for the French return creates errors in the declared gain. Use consistent methodology: either annual average rates or transactional spot rates for both the purchase year and the sale year, as your advisor recommends and as is consistent with the methodology used in prior French returns.

Practical Checklist

Before deciding whether and when to sell: calculate the date three years from when you last occupied the home as your principal residence. Mark this as the Section 121 window deadline. If that date is within two years, plan the sale timeline now.

Calculate the current estimated gain: sale price estimate minus adjusted basis (purchase price plus improvements minus depreciation if any).

If the gain exceeds the Section 121 exclusion limit: model the US tax on the excess gain, the French tax credit interaction, and the NIIT exposure for the proposed sale year.

If the home has been rented: calculate accumulated depreciation and model the recapture tax separately.

Engage a cross-border tax professional before listing the property for sale, not after the offer is accepted and the closing date is set. Tax planning for a home sale works before the transaction, not after.

After the sale closes: report the sale on Form 8949 and Schedule D of the US return for the tax year of closing. File Form 2048-IMM within the month that follows the sale, then show the gain on Form 2047 (cadre 3) and on line 3VZ of Form 2042 C of your French return. Confirm with your advisor how the Section 121 excluded portion is treated on the French return given your specific situation.

For the full US tax return framework including capital gains declarations and Form 2047 mechanics, see our French income tax return guide and our US taxes in France guide.

When to Get Help

The sale of a US home after moving to France is one of the clearest situations where professional support pays for itself. The Section 121 exclusion, the French reporting requirement, the prélèvements sociaux question, and the NIIT interaction create a combined picture that a US-only or French-only tax preparer will not handle correctly. A cross-border tax professional who works with both the US Form 1040 and the French Form 2042 is essential for any US real estate sale that occurs after establishing French tax residency.

For Americans who are planning a US home sale and want to ensure the transaction is handled correctly across both systems, the orientation establishes the framework before the sale, which is when it is most useful.

FAQ

How long do I have to sell my US home after moving to France to keep the Section 121 exclusion?

You have approximately three years from the date you last used the home as your principal residence. The Section 121 use test requires two years of use as your principal residence within the five years immediately preceding the sale. If you moved to France in January 2024 and have not lived in the home since, you must sell before approximately January 2027 to meet the use test. After that date, none of your qualifying use falls within the five-year lookback window, and the exclusion is unavailable. The exclusion amount is $250,000 for single filers and $500,000 for married filing jointly. Gain above the exclusion is taxable as long-term capital gains. Plan the sale timeline from the day you vacate the home as a principal residence, not from the day you arrive in France.

Does France tax the gain from selling my US home if I am a French resident?

Yes, in principle. As a French tax resident, you are subject to French tax on worldwide income, including gains from the sale of foreign real estate. The US-France treaty provides a credit mechanism that prevents true double taxation: France grants a credit equal to the US tax paid on the gain, capped at the French tax on it, so the effective combined rate approximates the higher of the two applicable rates rather than the sum. The US-side Section 121 exclusion reduces US tax liability, but the treatment of the excluded gain in France depends on the treaty application in your specific situation. Prélèvements sociaux (approximately 17.2%) may also apply on top of income tax. The French obligation requires filing Form 2048-IMM within the month that follows the sale and showing the gain on Form 2047 (cadre 3) and on line 3VZ of Form 2042 C, even if the US return shows minimal taxable gain.

Do I need to report the sale of my US home on FBAR or FATCA forms?

No. FBAR (FinCEN Report 114) and the FATCA Form 8938 cover foreign financial accounts and specified foreign financial assets, respectively. A US property is not a financial account. The sale itself is not a reportable event under either framework. What may trigger FBAR reporting is the financial account into which the sale proceeds flow, and the FBAR covers only accounts located outside the United States: proceeds deposited into a US bank or brokerage account are not FBAR-reportable, but if you move them to a French account, or to any other account outside the US, and your non-US accounts together exceed $10,000 at any point during the calendar year, those accounts must be declared on FinCEN 114. The mirror obligation applies in France, where your US accounts are the foreign ones and are declared on Form 3916. The proceeds themselves are not the reportable item: the account holding them is.

What is depreciation recapture and how does it affect the sale of a rented US home?

If you rented your US home at any point and claimed depreciation deductions on your US tax return, those deductions reduced your adjusted basis in the property. When you sell, the IRS recaptures those deductions as unrecaptured section 1250 gain, taxed at a maximum 25% federal rate rather than a flat 25%, regardless of how long you owned the home or whether the rest of the gain qualifies for lower long-term capital gains rates. The Section 121 exclusion does not apply to the recaptured depreciation portion of the gain. For example, if you accumulated $50,000 in depreciation deductions over several years of renting the home, $50,000 of the sale gain is subject to that recapture rate, for at most $12,500 in US federal tax on that portion. This applies on top of any capital gains tax on appreciation above the depreciation recapture amount. If your home was rented, calculate the depreciation recapture before modeling the total sale tax cost.

What forms do I need to file in France when I sell my US home?

The sale of a building is declared on Form 2048-IMM, filed within the month that follows the sale, and the gain taxed at 19 percent is shown on Form 2047 (cadre 3) and on line 3VZ of Form 2042 C. The gain is calculated in euros, converting both the adjusted cost basis and the sale proceeds at appropriate exchange rates. The notice of Form 2047 states that, where the gain was taxed at source abroad, a credit may be deducted from the French tax computed on these declarations, depending on the country and the treaty. Additionally, if the sale proceeds were deposited into a US financial account, ensure that the account is declared on Form 3916 (foreign account declarations) with your French return.

Conclusion

The Section 121 exclusion is one of the most valuable provisions in the US tax code for homeowners, and most Americans who move to France are eligible to use it, provided they sell before the three-year window closes. The French reporting obligation exists independently of the US tax result: the sale must be declared on the French return even when US liability is minimal or zero.

The lever that most directly affects the total tax outcome is the sale timing relative to the Section 121 window. It requires planning before the transaction, not after.

The timing of the sale relative to your residence date can change the tax outcome materially, and a consulting call before the transaction is worth far more than any planning after it.