US and UK Tax Advisors Foreign Inheritance Reporting |

US and UK Tax Advisors Foreign Inheritance Reporting |

US and UK Tax Advisors: Foreign Inheritance Reporting

US and UK Tax Advisors on Foreign Inheritance

Inheriting from a UK parent feels personal, not like a tax compliance event — but for a US citizen living in the UK, receiving that inheritance triggers a specific set of US information reporting obligations that have nothing to do with whether US tax is actually owed. Furthermore, US and UK tax advisors who work across both systems find that foreign inheritance reporting is one of the most consistently missed obligations for UK-resident US citizens, because the UK probate process does not indicate that a separate US filing requirement exists. The penalty for missing the report can be up to 25% of the entire inheritance value — a sum that shocks most clients who discover it years after the event.

This article explains the US reporting duties triggered by a foreign inheritance, why the obligation exists independently of any US tax, and what US and UK tax advisors do to ensure everything is handled correctly from the moment the inheritance is received. It is written for US citizens who are UK residents and who have inherited or expect to inherit assets from UK parents, grandparents, or other non-US persons.

What Are US and UK Tax Advisors?

US and UK tax advisors are cross-border tax professionals with qualifications and active practice in both US federal tax and UK tax, who advise clients simultaneously on both systems and can identify where the two interact for a single life event, such as receiving an inheritance. Furthermore, in the foreign inheritance context, this requires combining knowledge of IRC Section 6039F — the US statutory basis for Form 3520 inheritance reporting — with the UK probate process, the UK inheritance tax rules, and the interaction between the US step-up in basis for inherited assets and the UK CGT position on the same assets from the date of inheritance. Specifically, the most important distinction between a UK solicitor handling the probate and experienced US and UK tax advisors is the ability to identify every US information return obligation triggered by the inheritance and to file all of them by the correct deadlines before the automatic penalty regime activates.

The IRS guidance on reporting foreign inheritances on Form 3520 is at https://www.irs.gov/forms-pubs/about-form-3520. Additionally, the HMRC guidance on UK IHT and probate is at https://www.gov.uk/valuing-estate-of-someone-who-died.

Why Foreign Inheritance Reporting Matters in 2026

The Form 3520 Penalty Is Severe

Form 3520 is the US annual return that reports transactions with foreign trusts and the receipt of certain foreign gifts and inheritances. Furthermore, under IRC Section 6039F, a US person who receives money or property from a foreign person with an aggregate value exceeding $100,000 in a calendar year must file Form 3520 by the due date of their income tax return for the year of receipt. Specifically, the automatic penalty for failure to file Form 3520 for a foreign inheritance is the greater of $10,000 or 25% of the value of the unreported inheritance — a penalty structure that produces very large liabilities for significant inheritances received without US reporting. For example, a UK-resident US citizen who inherited £450,000 from a parent without filing Form 3520 has a theoretical automatic penalty of approximately $141,750 for the first year of non-compliance alone.

FATCA Creates a Data Trail from UK Probate

The UK probate process generates records of estate values, beneficiary identities, and asset distributions. Furthermore, UK financial institutions that release inherited funds to US-person beneficiaries are required under the UK-US FATCA Intergovernmental Agreement to report those account transfers to HMRC, which then exchanges the data with the IRS. Consequently, a UK-resident US citizen who inherited cash from a UK bank account and received the proceeds into their own UK bank account has likely had that transfer reported to HMRC through the receiving bank's FATCA compliance program. The AICPA confirms on its website (https://www.aicpa.org) that foreign inheritance reporting is one of the top areas of IRS enforcement focus, as FATCA data-matching capabilities have expanded.

The Stepped-Up Basis Is a Major Opportunity

One of the most valuable planning opportunities that US and UK tax advisors identify for UK-resident US citizens who inherit foreign assets is the IRC Section 1014 step-up in basis. Specifically, the US cost basis of inherited assets is stepped up to the fair market value as of the date of the decedent's death, eliminating all capital gains that accrued during the decedent's lifetime for US tax purposes. Consequently, a beneficiary who sells inherited UK shares immediately after probate pays little or no US capital gains tax — but only if the step-up basis has been correctly established through a professional independent valuation at the date of death. Many UK probate practitioners do not obtain valuations specifically for US basis purposes, and that oversight costs beneficiaries real money when they eventually sell.

US Reporting Obligations for Inherited UK Assets

Form 3520: What It Reports and When

Form 3520 Part IV is required for any US person who receives money or property from a foreign person with an aggregate value exceeding $100,000 in a calendar year, including cash, investments, real estate, and other assets. Furthermore, the form is due on the same date as the US income tax return — April 15 for most filers, extended to October 15 where a Form 4868 extension has been filed. Additionally, the $100,000 threshold is assessed on the aggregate value of all amounts received from foreign persons during the calendar year — multiple smaller inheritances from different UK relatives in the same year can together exceed the threshold, and each trigger the filing obligation. The IRS Form 3520 instructions are at https://www.irs.gov/forms-pubs/about-form-3520.

FBAR for Inherited Foreign Accounts

Where the inherited assets include a UK bank account transferred to the beneficiary's name, the FBAR reporting obligation begins from the date the beneficiary becomes the account holder. Furthermore, where the inherited account has a value exceeding $10,000 at any point during the calendar year — which is almost always the case — the FBAR must be filed for the calendar year of inheritance covering the period from the date of inheritance to the end of the year. Additionally, where the beneficiary was previously unaware of the FBAR obligation and has held the account for multiple years without filing, the streamlined foreign offshore procedures provide the correction route for non-wilful non-filers. The FBAR guidance is at https://www.fincen.gov/financial-crimes-enforcement-network/fbar.

Form 8938 for Inherited Financial Assets

Where the inherited assets include financial accounts, securities, or other specified foreign financial assets as defined under FATCA, the aggregate value of all such assets must be included in the Form 8938 calculation for the year of inheritance and all subsequent years. Furthermore, Form 8938 is required where the aggregate value of all specified foreign financial assets exceeds $200,000 at the end of the tax year or $300,000 at any point during the year for taxpayers living outside the United States. Consequently, a UK-resident US citizen who inherits an investment portfolio worth £300,000 — approximately $378,000 — almost certainly crosses the Form 8938 threshold in the year of inheritance, creating an additional reporting obligation alongside the Form 3520.

Managing a Foreign Inheritance: Practical Steps

Step 1 — Contact a cross-border adviser immediately after the death.

Notify a cross-border adviser as soon as possible after the death — ideally before any assets are transferred or accounts are released through the probate process. Furthermore, the US basis step-up under IRC Section 1014 must be supported by valuations as at the date of death, and those valuations are most credibly obtained before the estate is distributed rather than retrospectively months or years later. Additionally, confirm the aggregate value of all assets being received to assess the Form 3520 filing threshold and to identify any assets that require separate treatment, such as interests in a UK trust or UK company.

Step 2 — Obtain professional valuations at the date of death.

Commission independent professional valuations of every inherited capital asset — investment portfolios, real estate, business interests, art and collectibles — as at the date of the decedent's death. Furthermore, the valuations must be conducted by qualified independent professionals using methodologies that would withstand IRS scrutiny — for real property, a valuation by a RICS-qualified surveyor; for investment portfolios, the published market prices on the date of death. Additionally, retain all valuation reports permanently, since the US basis step-up must be supported by contemporaneous evidence at the date of any future disposal of the inherited asset. The IRS guidance on inherited property basis is at https://www.irs.gov/publications/p551.

Step 3 — File Form 3520 by the income tax return due date.

Prepare and file Form 3520 Part IV reporting the receipt of the foreign inheritance, listing each asset received with its fair market value at the date of receipt converted to US dollars, and confirming the identity and relationship of the foreign person. Furthermore, the form is due by April 15 of the year following the year in which assets are received, with an automatic extension to October 15 where Form 4868 was filed. Additionally, where the estate is distributed in tranches over multiple years — as is common in complex UK probates involving property sales — a separate Form 3520 must be filed for each calendar year in which distributions exceed $100,000.

Step 4 — Add inherited accounts to FBAR and Form 8938.

Update the annual FBAR and Form 8938 filings to include all newly inherited foreign financial accounts and specified foreign financial assets from the date on which the beneficiary became the account holder. Furthermore, when the inheritance occurs mid-year, the FBAR for the year of inheritance must cover the inherited accounts for the portion of the year the beneficiary held them. Additionally, assess whether any inherited foreign trust or company interest creates separate Form 3520, Form 3520-A, or Form 5471 filing obligations in addition to the annual FBAR and Form 8938.

Step 5 — Review the UK IHT and CGT position on the same assets.

Confirm the UK IHT position on the estate — including whether the estate paid any IHT on assets passing to the US-citizen beneficiary — and assess whether the IHT paid can be credited against any US estate tax liability where the decedent was also a US person or had US situs assets. Furthermore, confirm the UK CGT base cost of the inherited assets — which is the probate value at the date of death — and compare it with the US stepped-up basis to identify any divergence for future disposal planning. The HMRC IHT guidance is at https://www.gov.uk/inheritance-tax.

Case Study: US Citizen in Edinburgh, UK Estate

Our team was engaged by a US citizen who had lived in Edinburgh for eight years and inherited from her UK-national mother, who died in late 2023. The estate comprised a UK investment portfolio valued at £380,000 at the date of death, a UK residential property valued at £420,000, and cash in three UK bank accounts totaling £95,000. The estate paid UK IHT of £42,000, and the assets were transferred to the beneficiary in spring 2024. No Form 3520 had been considered for either 2023 or 2024.

After reviewing the timing of the estate distribution, we confirmed that the primary Form 3520 filing obligation arose for 2024 — the calendar year in which assets were actually received — since the aggregate value received was approximately $1.13 million at the applicable exchange rate, well above the $100,000 threshold. Furthermore, no Form 3520 was required for 2023 since no assets had been distributed to the beneficiary in that year. Additionally, we obtained RICS-qualified property valuations and portfolio close-of-business prices at the date of death to establish the US stepped-up basis: investment portfolio at approximately $479,800, property at approximately $530,400, and cash at the one-for-one USD equivalent.

We prepared the Form 3520 Part IV for 2024, updated the FBAR for 2024 to include the three inherited UK bank accounts from the date of receipt, and updated Form 8938 to include the investment portfolio and property — the aggregate value substantially exceeded the $300,000 threshold for UK-resident filers. Furthermore, we advised the client that if she sold the inherited property immediately, the US capital gains tax would be calculated only on the appreciation above the $530,400 stepped-up basis — not on the full proceeds — resulting in a very low US liability compared with what would have arisen without a step-up. The entire engagement was coordinated alongside the UK solicitor's probate work, ensuring both US and UK obligations were addressed in parallel.

Common Mistakes with Foreign Inheritance Reporting

Mistake 1 — Assuming No US Tax Means No US Filing

The most common mistake is assuming that because the US imposes no inheritance tax on amounts received by US citizens from foreign persons, there is no US reporting obligation at all. Furthermore, Form 3520 is an information return — it reports the existence and value of the inheritance to the IRS without creating a tax liability — and the penalty for not filing it is just as severe as if tax were owed and unpaid. The correct approach is to file Form 3520 for each year in which inheritances from foreign persons exceed $100,000, regardless of whether any US tax is due on the inherited assets.

Mistake 2 — Missing the Filing Deadline Because of Ongoing Probate

The Form 3520 due date is tied to the US income tax return due date — April 15 with extension to October 15 — not to the completion of UK probate, which may take 18 months or two years. Furthermore, the obligation arises in the calendar year in which the beneficiary actually receives the assets, not in the year the grant of probate is issued. The correct approach requires monitoring the calendar year of each distribution and filing the Form 3520 for that year on time, even if probate is not yet complete.

Mistake 3 — Not Getting Date-of-Death Valuations for US Basis

The IRC Section 1014 step-up in basis is one of the most valuable US tax benefits associated with inheriting foreign assets. Still, it can only be claimed where a reliable independent valuation of the assets at the date of death is obtained and retained. Furthermore, many UK probate valuations are conducted for IHT purposes only and may not produce the specific US dollar basis figure required. The correct approach requires commissioning a separate US-basis valuation — confirmed by a qualified independent professional — for every capital asset in the inherited estate, to be retained permanently as supporting documentation. IRS basis guidance is at https://www.irs.gov/publications/p551.

Mistake 4 — Not Adding Inherited Accounts to the FBAR

Where the inheritance includes a UK bank account transferred to the beneficiary's name, the FBAR obligation begins from the date the beneficiary becomes the account holder. Furthermore, beneficiaries who are already FBAR-compliant for their existing accounts sometimes fail to add the newly inherited account for the year of inheritance, since the account may not appear in their banking records until probate is complete. The correct approach requires reviewing the FBAR account list for the year of inheritance and adding every newly transferred account from the date of transfer.

Mistake 5 — Treating Estate Income During Probate as Tax-Free

Income generated by inherited assets during the period of administration — interest, dividends, rent — is taxable as income to the beneficiary in the year it is received, regardless of whether probate has completed. Furthermore, many UK-resident US citizens assume that estate income during administration is part of the inheritance and not separately reportable, when the IRS treats such income as taxable in the year of receipt. The correct approach is to report all income received from the estate during the administration period on the US income tax return, separately from the Form 3520 inheritance report.

Mistake 6 — Missing the IHT Treaty Credit Where Both US and UK Tax Apply

Where the deceased was also a US person — a dual citizen or green card holder — the estate may have both a US Form 706 estate tax obligation and a UK IHT obligation on the same assets. Furthermore, the US-UK Estate and Gift Tax Treaty provides a credit for IHT paid in the UK against the US estate tax on the same UK situs assets, and that credit is available only if Form 706 is filed correctly, with the treaty credit specifically claimed. The correct approach requires confirming the decedent's US person status before assuming no Form 706 obligation exists. HMRC IHT guidance is at https://www.gov.uk/inheritance-tax.

Get in Touch

At US-UK Tax, our team of Chartered Tax Advisers (CTA), Enrolled Agents (EA), and Certified Public Accountants (CPA) — members of the Chartered Institute of Taxation (CIOT) and the American Institute of CPAs (AICPA) — are US and UK tax advisors who guide UK-resident US citizens through every US reporting obligation triggered by a foreign inheritance. Furthermore, we prepare the Form 3520 inheritance report, update the FBAR and Form 8938 for inherited accounts, establish the US stepped-up basis for each inherited asset through coordinated valuation work, and review the UK IHT treaty credit position where the deceased was also a US person. We work directly with UK probate solicitors, executors, and estate managers to ensure the US reporting timeline is met in parallel with the UK probate process.

Contact our team today to begin a confidential review of your inherited estate's US reporting obligations. Email hello@us-uktax.com, call 0333-8807974, or visit https://www.us-uktax.com/contact/ to book a consultation.

Conclusion

Receiving a foreign inheritance is one of the most commonly missed US reporting triggers for UK-resident US citizens, because the UK probate process does not indicate that a separate US information return is required, and because the absence of US tax on the inheritance creates a widespread assumption that no reporting obligation exists. Furthermore, the Form 3520 penalty of up to 25% of the unreported inheritance value is among the most severe in the international information-return regime. Consequently, engaging experienced US and UK tax advisors who can identify every reporting obligation from the moment of death — Form 3520, FBAR for new accounts, Form 8938, and the IRC Section 1014 stepped-up basis valuation — is the only way to manage the US dimension of a foreign inheritance correctly.

The three most important actions for any UK-resident US citizen who has recently inherited or expects to inherit from a UK relative are: first, commission professional date-of-death valuations for every capital asset before assets are sold or values change; second, file Form 3520 by the US income tax return due date for the calendar year assets are received, regardless of whether UK probate is complete; and third, update the annual FBAR and Form 8938 to include all newly inherited foreign financial accounts from the date of receipt. Contact US-UK Tax at hello@us-uktax.com or call 0333-8807974 to begin a confidential review today.

Contact Us

US-UK Tax | hello@us-uktax.com | 0333-8807974

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FAQs

Q: Do I need to file a US return when I inherit from a UK parent?

Yes, Form 3520 must be filed if the aggregate inheritance value exceeds $100,000 in a calendar year. No US tax is due on the inheritance, but the penalty for failing to file is up to 25% of the unreported value.

Q: What is the Form 3520 deadline for a foreign inheritance?

Form 3520 is due by April 15 of the year after you receive the inheritance, extended to October 15 where a Form 4868 extension was filed. The trigger is the calendar year assets are received — not the year of death or probate completion.

Q: Does inheriting a UK bank account trigger FBAR reporting?

Yes, from the date you become the account holder. The FBAR for the year of inheritance must include the account for the period you held it. If the balance exceeded $10,000 at any point during that period, the filing obligation applies.

Q: What is the IRC Section 1014 stepped-up basis for inherited assets?

Section 1014 resets your US cost basis to the fair market value at the date of death. A professional independent valuation at that date is required. This eliminates all capital gain accrued during the decedent's lifetime for US tax purposes.

Q: Is income from an inherited estate taxable in the US during probate?

Yes. Income from estate assets during administration — interest, dividends, rent — is taxable income to the beneficiary in the year received, reported on the US income tax return separately from the Form 3520 inheritance report.

Q: What is the penalty for not filing Form 3520 for a foreign inheritance?

The automatic penalty is the greater of $10,000 or 25% of the unreported inheritance value per year of non-filing. For a £400,000 inheritance, this can exceed $125,000 — making timely filing critically important even when no US tax is owed.