WSML is an Ireland-domiciled UCITS fund that is generally a PFIC for US persons. The iShares III plc prospectus names this fund and makes no provision for a PFIC Annual Information Statement, which a QEF election needs for each year — so unless BlackRock (iShares) supplies one, the routes left are mark-to-market (if the listing qualifies) or the §1291 default.
Source: iShares III plc prospectus, checked .
As an accumulating share class, it reinvests income rather than paying it out. A later sale can still trigger §1291 tax and interest; the outcome depends on your holding period, transactions and election history.
By Danilson Ramos · Founder, Atamatax
Fund facts verified against issuer sources ·
No card · free draft · professional per-form preparation starts at $170 per Form 8621 (Bright!Tax’s published floor, no distributions); the PFIC package is a flat $499 for up to 25 Forms 8621, which you review and file.
If WSML is confirmed as a PFIC, you may need a separate Form 8621. For supported inputs the paid package gives a Form 8621 for each supported PFIC — a pre-filled official PDF only for a tax year whose official form is integrated and released, otherwise a worksheet with every figure mapped to the form's lines; review its notes and complete any remaining fields before filing outside Atamatax.
WSML pays out nothing, so there may be no cash distribution to enter in a §1291 excess-distribution calculation while you hold. Separate annual Form 8621 reporting can still apply.
Mark-to-market (§1296) taxes the annual paper gain as ordinary income — and an accumulating fund sends you no cash to pay it with. Worth planning before you elect.
WSML tracks global developed-market small-cap equities. Small-cap sleeves are typically bought as a long-horizon satellite position and then left alone — which is precisely the holding pattern §1291 is built to penalise.
A disposition gain under the default rules is allocated across the days you held WSML. Earlier PFIC-year amounts use that year's highest applicable tax rate and can carry interest; current-year and pre-PFIC amounts are ordinary income in the current return. The holding period, gain and election history determine the result for this position.
WSML pays you nothing. The dividends from the underlying shares are reinvested inside the fund instead of hitting your account. Under the default §1291 rules, there may be no cash distribution to test as an excess distribution while you simply hold, while a later disposition can still trigger the allocation and interest-charge regime. Separate annual Form 8621 reporting can also apply during the holding period.
A sale at a gain can still create a substantial bill. Under §1291, the gain is allocated across the holding period: current-year and pre-PFIC amounts are ordinary income, while earlier PFIC-year amounts use the highest applicable tax rate for each year and can carry interest. That interest runs between the relevant return due dates without extensions. Accumulation alone does not establish which share class produces the larger tax bill.
One knock-on worth planning around: a mark-to-market election under §1296 taxes the annual paper gain as ordinary income — but WSML distributes no cash, so that tax has to be funded from somewhere else every year.
WSML is the iShares MSCI World Small Cap UCITS ETF (Accumulating), ISIN IE00BF4RFH31. Match the ticker — and the ISIN, where your statement shows one — to this line before reading the mechanics above as yours.
WSML follows an MSCI index; no other global developed-market small-cap equities fund in this registry shares its wrapper and domicile, so there is no like-for-like sibling page to compare it with.
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A routing read, not a determination. Whether a fund is a PFIC, whether an exception applies and what a prior year needs are established when the holdings are screened; the route above says where that happens and what it costs.
This is a screening assessment based on published vehicle facts and the statutory tests—not a classification based on domicile alone, and not individualized tax, legal, or investment advice — see our methodology (IRC §1297 et seq.). Confirm your specific situation with a licensed professional.
Primary sources (Cornell Legal Information Institute for the US Code and CFR; IRS.gov for forms, procedures, and treaty documents). This page is general information, not individualized tax or legal advice.
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