Three years of returns, twenty years of fund history: streamlined filing with PFICs

Figures relate to tax year 2023-2025 streamlined window

The IRS designed the streamlined procedures as the simple way back into the American system. Three years of returns, six years of bank reports, a signed statement and the tax with interest.

Funds break that simplicity. Streamlined filing PFIC work means a separate Form 8621 for each British fund in each of the three years. The tax on those funds can also depend on events long before the window opens.

This guide explains how British funds fit inside a streamlined package, where the work really sits, and which choices are still open when the returns are late.

Key takeaways

• A British unit trust, OEIC or ETF is usually a PFIC for an American shareholder.
• Funds inside a stocks and shares ISA count, even though Britain ignores them.
• Each streamlined filing PFIC return needs Form 8621 for every fund, unless an exception applies.
• Holdings of $25,000 or less, or $50,000 on a joint return, can avoid Part I if nothing was sold or distributed.
• Sales in the window are taxed under the section 1291 rules, which reach back to purchase.
• Most elections need a timely return, so late years usually take the default rules.
• Under the foreign procedures, no penalties apply to returns filed correctly, including information return penalties.
• Plan the regime for later years before the streamlined filing PFIC package is submitted.

What is a PFIC, and why do British funds qualify?

A passive foreign investment company is a foreign company whose income or assets are mainly passive, such as interest, dividends and gains. A British fund holds shares and bonds for investors, so almost every one meets the test. As a result, an American who owns a British fund owns a PFIC.

The label covers unit trusts, open-ended investment companies, investment trusts and ETFs listed in London. It covers them whether you hold them directly, through a platform or inside an ISA.

Congress wrote the rules to stop Americans deferring tax through offshore funds. Notably, they apply in full to ordinary savers who bought a tracker fund on a bank's advice.

Do streamlined returns need Form 8621 for each fund?

Yes, where a filing requirement exists. According to the IRS instructions for the foreign procedures, each late or amended return must include the required information returns. Form 8621 is one of those, so a submission with four funds across three years can need twelve of them before any exception applies.

The IRS page names Forms 3520, 5471 and 8938 as examples, but the rule is broader. Any information return that the year required belongs in the package, written up with the streamlined label.

Leaving them out has a cost beyond penalties. An unfiled Form 8621 keeps the statute of limitations open on the whole return, so the year never closes.

When does the $25,000 exception help?

If the total value of all your PFIC stock is $25,000 or less on the last day of the year, or $50,000 on a joint return, you need not complete Part I for a fund. However, the exception fails in any year you receive an excess distribution or sell any of that fund. So small holdings can drop out of the paperwork, provided nothing moved.

The threshold counts all PFICs together, not each one. For example, three funds worth $10,000 each total $30,000, which is over the single limit even though each fund is small.

Accumulation units also need care. A fund that reinvests income does not pay a distribution, so the exception can still hold. But a sale to switch funds within an ISA is a disposal, and it ends the exception for that year.

How does the default section 1291 tax work?

Without an election, a gain on sale and any excess distribution are spread across every day you held the fund. The IRS taxes the part that falls in earlier years at the highest rate for each of those years, plus an interest charge. Only the part that falls in the current year meets your normal rate as ordinary income.

An excess distribution is any amount above 125% of the average distributions in the three prior years. So a fund that suddenly pays more than usual can trigger the rule even without a sale.

This is where the streamlined window stops being simple. To spread a gain back to a purchase in 2012, you need the price, the date and every later distribution, even though you file only three years.

Why the fund history reaches past the three years

The streamlined procedures limit the returns you file, not the history the tax rules need. A sale in 2025 of a fund bought in 2015 spreads across ten years. So the calculation for one streamlined year depends on ten years of records.

In practice, the hardest part is gathering those records. Platforms often keep statements for six years, and switches between funds or providers break the trail. Our guide to missing records in streamlined filing covers reasonable reconstruction.

Where you cannot find a purchase price at all, a defensible estimate based on the fund's published prices is better than leaving the fund out. The written method should sit in the file.

Can you still make a QEF or mark-to-market election?

Usually not for the late years, because both elections normally need a timely filed return. A qualified electing fund election also needs an annual statement from the fund, which most British funds do not provide. So most streamlined filing PFIC cases take the section 1291 default for the window, then plan elections for later years.

The mark-to-market election suits listed funds and ETFs once your filing is current. It taxes the yearly rise in value as ordinary income and avoids the interest charge. However, the first year of the election still has to deal with the gain built up before it.

There is also a purging election, which treats the fund as sold so you can start afresh under a better regime. Our guide to the PFIC purging election explains when it is worth the tax it brings forward.

How the three PFIC regimes compare

The table shows why the default dominates late filings. It is the only regime that needs no earlier choice, so it applies to every year in the window unless an election was already in place.

Can British tax on a fund sale be credited?

Often yes, where the fund sat outside an ISA. British capital gains tax on the sale is a foreign tax on the same gain, so it can generally reduce the American tax on that excess distribution. Inside an ISA there is no British tax, so there is nothing to credit and the full American charge stands.

Timing still matters. The British tax year ends on 5 April, so a sale in May 2024 falls in the British 2024-25 year and the American 2024 year. Match the tax to the sale, not to the return that reports it.

Which exchange rate do you use for fund values?

Each purchase, distribution and sale converts to dollars at the rate on its own date. The year-end value for the $25,000 test uses the rate on the last day of the year. So the same fund can pass the exception one year and fail it the next with no change in units held.

For example, £20,000 of funds is $25,400 at $1.27 but $24,000 at $1.20. The first is over the limit and the second is under it. Our guide to exchange rates on a US return covers the sources the IRS accepts.

Are investment trusts and reporting funds different?

An investment trust is a listed company, but it is still usually a PFIC because its assets are passive. British reporting fund status helps with British tax on offshore funds, yet it does not make a fund a qualified electing fund for America. So neither label takes a fund outside the American rules.

Shares in an ordinary trading company are different. A British bank or supermarket share is not a PFIC, so it is reported as a normal capital gain. Separating funds from company shares is often the first useful step in a streamlined review.

What happens after the streamlined years?

Once your filing is current, you file Form 8621 every year on time like anyone else. That is the moment to choose a better regime, such as mark-to-market for listed funds. Many people also move their savings into American-domiciled investments held through a platform that accepts American clients, which ends the problem for new money.

Think of a streamlined filing PFIC package as a one-off catch-up, not a template for every later year. The window uses the default rules because it has to. After it, you can choose, and a good choice made early saves the interest charge on every future sale.

What about funds inside an ISA?

They are PFICs in exactly the same way, because America does not recognise the ISA shelter. Interest and dividends inside the ISA are taxable on the American return, and the funds need Form 8621 where no exception applies. Britain still treats the whole ISA as tax free.

That mismatch means no British tax to credit against the American tax. So the American tax on ISA funds is often the one real cost in a package that otherwise shows nothing owed.

Cash ISAs are simpler. They hold no funds, so the interest is just taxable interest, reported without Form 8621.

What about funds inside a British pension?

Funds inside a British pension generally follow different rules. The treaty usually defers American tax on pension growth, and the Form 8621 regulations include an exception for funds held through such a pension. So a workplace pension or SIPP invested in British funds does not normally create a separate PFIC filing.

The pension still needs reporting elsewhere, often on the FBAR and Form 8938. Our guide to Form 8938 and FATCA reporting explains which values go where.

Which route suits a streamlined filing PFIC case?

Americans living in Britain usually qualify for the foreign procedures, which carry no penalty. According to the IRS, returns properly filed under them are not subject to failure-to-file, accuracy or information return penalties. The domestic procedures, for those who do not meet the residency test, carry a 5% penalty on the highest year-end value of the unreported assets.

That 5% base can include the funds themselves. So a domestic filer with large British fund holdings pays a penalty on them as well as the PFIC tax, which makes the residency test worth checking carefully.

A worked example

Take an illustrative example of an American in Manchester with two funds in a stocks and shares ISA. Fund A was bought in 2016 for $20,000 and sold in 2024 for $32,000. Fund B is worth $15,000 and was never sold. The window covers 2023 to 2025.

1. PFIC value test: at the end of 2023, the two funds total about $43,000, above $25,000, so both need Part I for that year.
2. 2024: Fund A is sold, so its $12,000 gain is an excess distribution under section 1291.
3. The gain is spread over the roughly eight and a half years held, about $1,400 per year.
4. The 2024 share is taxed at the normal rate; earlier shares take each year's top rate plus interest.
5. Fund B alone at the end of 2024 and 2025 is $15,000 with no sale, so the exception removes Part I.
6. Result: three Forms 8621 for 2023 and 2024, with tax and interest on Fund A in the streamlined filing PFIC package.

We have rounded the figures and simplified the allocation. However, the shape is typical. One sale in the window drives almost all of the PFIC tax, and that sale needs records from 2016.

Does a non-willful statement need to mention the funds?

It should explain your whole failure, and funds often form part of the story. Form 14653 asks for specific reasons why you did not report income and file information returns. A clear account of buying an ISA on a bank's advice, without knowing the American rules, fits the non-willful standard well.

Vague statements are the main reason the IRS questions a certification. So name the accounts, say when you opened them and say how you learned of the rules.

Common mistakes and penalties with British funds

The most common mistake is treating an ISA as invisible because Britain does. The second is filing Form 8621 only in the year of sale. Both leave a gap that keeps the returns open.

• Leaving ISA funds off the American returns entirely.
• Applying the $25,000 test fund by fund rather than in total.
• Missing a switch between funds, which counts as a sale.
• Using a late election that the rules do not allow.
• Reporting a fund gain as an ordinary capital gain on Schedule D.
• Omitting the streamlined filing PFIC detail from the Form 14653 narrative.

Steps to include funds in a streamlined package

1. List every fund held at any time in the three years, inside and outside ISAs.
2. Gather purchase dates, prices and all distributions back to purchase.
3. Test the $25,000 or $50,000 exception at each year end.
4. Work out section 1291 tax and interest on every sale or excess distribution.
5. Complete Form 8621 for each fund and year that needs it, marked as streamlined.
6. Plan the election you want for the first year after your filing is current.

How US UK Tax Accountants helps

We prepare streamlined packages for Americans in Britain, with the fund work built in from the start rather than bolted on. That includes rebuilding fund histories from platform statements and published prices. Our streamlined filing service covers the returns, the FBARs and the certification.

In our practice, most fund holders find the tax far smaller than they feared, because the exception covers small holdings. The real effort is the records, and that is work we do every week.

If you hold British funds and have not filed, contact us and we will scope the package before you commit.

This article is general information, not personal tax advice. PFIC calculations depend on your own history, so take advice on your funds.

Last reviewed: 11 November 2026.