ISAC is an Ireland-domiciled UCITS fund that is generally a PFIC for US persons. We have not confirmed from a primary BlackRock (iShares) source whether it publishes a PFIC Annual Information Statement for this fund, and a QEF election needs that statement for each year — without it, the routes left are mark-to-market (if the listing qualifies) or the §1291 default.
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 not yet verified against an issuer source
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 ISAC 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.
ISAC 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.
Same fund, other listings: IUSQ (Xetra) · SSAC (USD) · ISIN IE00B6R52259. They are the same legal instrument; listing venue and currency do not change its entity classification.
ISAC tracks all-country world equities, spanning dozens of markets. A reasonable worry follows: does that mean dozens of issuer-level PFIC analyses? No. The tests apply to the fund vehicle you own, not separately to each portfolio company. If ISAC is confirmed as a PFIC, it is one PFIC holding for Form 8621 analysis.
Separate fund vehicles must generally be analyzed separately. Whether each produces a Form 8621 depends on its classification and the holder's reporting triggers and exceptions; diversification inside one vehicle is therefore usually less complex to report than the same exposure spread across five vehicles. If you hold the other line instead — IUSQ (Xetra) or SSAC (USD) — the entity-classification analysis is unchanged: it is the same legal instrument under another listing.
ISAC 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 ISAC distributes no cash, so that tax has to be funded from somewhere else every year.
A word on which line this is. ISAC is the London listing, quoted in sterling, while IUSQ are the same ISIN (IE00B6R52259) on other venues or in other currencies. Form 8621 is filed in US dollars, so a sterling line means translating your purchase, your distributions, and your disposal proceeds into USD at the appropriate rates — and because §1291 allocates the gain back across the whole holding period, the exchange rate on the day you bought matters just as much as the one on the day you sold.
ISAC is the iShares MSCI ACWI UCITS ETF (GBP, LSE), ISIN IE00B6R52259. The registry also records SSAC (USD) as another line of the same iShares fund. Match the ticker — and the ISIN, where your statement shows one — to this line before reading the mechanics above as yours.
IUSQ is the same security as ISAC under another ticker — the same ISIN, IE00B6R52259. Whichever line your broker shows, ISAC and IUSQ are one holding for Form 8621: one fund, one holding period, one election history.
Nine other all-world equity funds in this registry raise the same question as ISAC: VWRA, VWRL, VWCE, VHYL, FWRG, VWRP, SPYI, VWRD and WEBN. ISAC follows an MSCI index, as SPYI does; VWRA, VWRL, VWCE, VHYL, FWRG, VWRP and VWRD follow FTSE. The §1297 analysis does not change from one issuer to the next, and each fund is its own PFIC — its own Form 8621, holding period and election history. What does change is the share class.
From one fund to the whole case
Four questions — how many funds, for how long, whether Forms 8621 were ever filed, whether the returns are current — and a route into the preparation that fits, with what it costs. Nothing you answer leaves this page.
Free, no account, nothing you answer leaves this page. Open the full portfolio scanner
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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