Strategy Snapshot
Form 8621 is often the surprise form that shows up after someone buys a foreign mutual fund or holds investments through a non-U.S. account. The real issue is not just the filing burden. It is that PFIC taxation can turn otherwise normal investment gains into a very expensive U.S. tax problem.
Owning foreign mutual funds, foreign ETFs, or stock in a foreign corporation that mostly earns passive income.
A separate Form 8621 may be required for each PFIC, and the default tax regime can produce punitive results.
Assuming a non-U.S. brokerage account is fine as long as it is reported on FBAR or Form 8938.
What Is Form 8621?
Form 8621 is the IRS information return used by a U.S. person that owns shares in a Passive Foreign Investment Company (PFIC) or a Qualified Electing Fund (QEF). In practice, this is one of the most common international tax traps for Americans who invest outside the U.S., especially through foreign brokerage accounts.
Under the current IRS instructions, a U.S. person generally files Form 8621 if they:
- Receive certain direct or indirect distributions from a PFIC
- Recognize gain on a direct or indirect sale of PFIC stock
- Report information for a QEF election or mark-to-market election
- Make an election reportable in Part II of the form
- Are required to file an annual report under section 1298(f)
What Counts as a PFIC?
Under the IRS instructions, a foreign corporation is generally a PFIC if it meets either of these tests:
- Income test: at least 75% of its gross income is passive income
- Asset test: at least 50% of its assets produce or are held to produce passive income
That definition sweeps in far more than people expect. Common examples include:
- Foreign mutual funds
- Many foreign ETFs
- Non-U.S. money market or investment funds
- Some foreign holding companies
- Certain foreign corporations held for investment rather than active operations
For many expats, the practical problem is simple: the “normal” investment products offered in their country of residence may be PFICs for U.S. tax purposes.
Why the PFIC Rules Are So Expensive
The filing burden is bad enough, but the real problem is the tax regime. If you hold a PFIC under the default section 1291 rules, excess distributions and gains can be allocated back across prior years and taxed in a much harsher way than a normal capital gain.
That is why PFIC planning is less about filling out a form and more about avoiding the wrong investment structure in the first place.
One Form Per PFIC
The IRS instructions are explicit on one point that catches people off guard: you may need a separate Form 8621 for each PFIC. If you own five foreign funds, the compliance burden may not be “one international form.” It may be five separate PFIC filings attached to the return.
The pain of Form 8621 is not just complexity. It is repetition across every foreign fund in the portfolio.Where the compliance burden comes from
Elections Matter
Not every PFIC is taxed the same way. The form is also used for elections that can change the tax result, including:
- QEF election
- Mark-to-market election under section 1296
These elections can improve the outcome in the right facts, but they depend on timing, available records, and whether the fund provides the information required to support the election. Inference: for many retail investors, the hardest part is not choosing the election conceptually, but getting the underlying annual data needed to make it work.
The current IRS instructions for Form 8621 were revised in December 2025, including updates to Part V for currency-code and U.S.-dollar reporting lines. That is a reminder that this is an actively maintained filing area, not stale legacy paperwork.
FBAR, Form 8938, and Form 8621 Are Different Problems
Taxpayers often ask whether reporting the account on FBAR or Form 8938 is enough. It is not.
Quick Comparison
| Form | What it does | Why it does not replace Form 8621 |
|---|---|---|
| FBAR | Reports foreign financial accounts to FinCEN | Does not determine PFIC tax treatment |
| Form 8938 | Reports specified foreign financial assets to the IRS | Does not replace PFIC reporting |
| Form 8621 | Reports PFIC ownership, elections, distributions, and gain | Drives the actual PFIC compliance and tax result |
Common Situations That Trigger Review
- A U.S. expat buys local-country mutual funds through a non-U.S. broker
- A dual resident keeps legacy investments in a home-country fund
- A U.S. taxpayer inherits foreign pooled investments
- A foreign corporation in the ownership chain turns out to be passive rather than operating
This is also why Form 8621 often shows up alongside other international filings such as Form 5471, Form 3520 analysis, or FBAR / FATCA review.
When to Seek Help
If you already own non-U.S. pooled investments, Form 8621 is worth reviewing before the return is filed rather than after. If you have not invested yet, the best planning move is often selecting the right investment structure up front. PFIC problems are much cheaper to avoid than to unwind after several years of unfiled forms or bad elections.
Last updated: 2026