If you have decided a single developed-world fund will be the core of your portfolio, you quickly run into two names that keep coming up: the Invesco MSCI World UCITS ETF (usually seen as SPPW or EQQW on European exchanges) and the iShares Core MSCI World UCITS ETF (IWDA, SWDA or EUNL depending on the listing). Both are Irish-domiciled, both accumulate dividends rather than paying them out, both are priced in US dollars under the bonnet, and both track exactly the same index of roughly 1,400 large and mid-cap stocks across 23 developed markets.
So on paper they look like twins. The honest answer is that for most people the choice barely matters, and either is a decision you will not regret. But there is one real structural difference worth understanding before you commit years of contributions: iShares owns the actual shares, while Invesco tracks the index synthetically using swaps. That single choice drives everything else.
I have held a physically replicated MSCI World tracker for years, and I have also used synthetic funds for US exposure to capture that tax edge. Here is how I weigh the two, without pretending either is a secret hack or a hidden landmine.
The core difference: physical versus synthetic replication
The iShares Core MSCI World is a physical fund. When you buy it, the fund uses your money to buy the underlying stocks, from Apple and Microsoft down through the smaller constituents. It may not hold every single name at all times, using optimised sampling to keep costs down, but the assets are real equities that belong to fund shareholders. This is the structure most European investors instinctively prefer, and it is the reference product in the category.
Methodology: every shortlist on this page applies our how we compare ETFs.
The Invesco MSCI World is a synthetic, or swap-based, fund. Instead of owning the index stocks directly, it holds a basket of collateral securities and enters into a total return swap with one or more investment-bank counterparties. Those counterparties agree to pay the fund the exact return of the MSCI World index in exchange for the return on the collateral basket. You still track the same index, but through a contract rather than direct ownership. I explain the mechanics and the genuine risks of this in more depth in my guide to synthetic versus physical replication.
Why synthetic can quietly win on tax
The reason Invesco bothers with swaps is not laziness, it is US dividend withholding tax. A physical fund that owns US shares has 15% withheld on the dividends those shares pay, under the US–Ireland tax treaty. That drag is small but real, and shows up in long-run tracking. A well-structured swap-based fund can, in certain conditions, receive the index return effectively gross of that withholding, because of how US rules treat total-return swaps on indices. Since the US is around 70% of the MSCI World, even a fraction of a percent recovered each year can offset Invesco’s costs and occasionally edge it ahead of physical peers on tracking.
Cost: both are cheap, the gap is tiny
On headline fees these two are almost indistinguishable. As a 2026-vintage figure to verify on each factsheet, the iShares Core MSCI World carries a TER around 0.20% a year and the Invesco MSCI World around 0.19%. On a €10,000 holding that is about one euro a year, which is noise.
What matters more than the TER is tracking difference, the gap between the index return and what the fund actually delivered after costs and tax. This is where the synthetic structure shows up. In good years Invesco’s tracking has been very tight, sometimes tighter than physical rivals, because of the withholding advantage. But swap terms change, and the edge is not guaranteed. I would not switch a whole portfolio for a few basis points, but a data-driven investor should check recent tracking on both. The EUNL versus IUSQ fee analysis shows how small these gaps get even between two physical funds, and the cheapest MSCI World UCITS ETF comparison ranks the whole field on cost.
Fund size, liquidity and track record
This is where iShares has a genuine, measurable lead. The iShares Core MSCI World family (IWDA, SWDA, EUNL are the same fund on different exchanges) is one of the largest equity ETFs in Europe, with tens of billions of euros in assets and a track record stretching back to 2009. That scale means tight spreads, deep liquidity on every major exchange, and effectively zero risk of the fund closing for lack of interest.
The Invesco MSCI World is a serious multi-billion-euro fund, not a thinly traded curiosity. But it is smaller and younger than the iShares behemoth, and its spreads on some listings can be marginally wider. For a buy-and-hold investor placing occasional limit orders, that rarely costs anything meaningful. For very large lump sums, it is one more reason iShares feels like the default.
Counterparty risk: how worried should you be?
The word “synthetic” makes many European investors nervous, and I understand why. The fair version of the risk is this: with a swap, part of your return depends on the counterparty banks honouring the contract. If one failed, there could in theory be a shortfall between the collateral held and the index value.
In practice this is heavily mitigated. UCITS rules cap exposure to any single swap counterparty at 10% of fund assets, Invesco uses multiple counterparties, the swaps reset frequently, and the fund holds a collateral basket marked to market. The realistic exposure at any moment is small, not the whole fund. It is not zero, though, and that is the honest trade-off: a modest structural risk in exchange for a potential tax edge. A physical fund removes that particular risk but carries its own quieter one through securities lending. Neither is risk-free, they are just different risks.
Invesco MSCI World versus iShares Core MSCI World at a glance
| Feature | Invesco MSCI World (SPPW/EQQW) | iShares Core MSCI World (IWDA/SWDA/EUNL) |
|---|---|---|
| Index | MSCI World (23 developed markets) | MSCI World (23 developed markets) |
| Replication | Synthetic (swap-based) | Physical (owns the stocks) |
| Domicile | Ireland | Ireland |
| Distribution | Accumulating | Accumulating |
| TER (approx, verify) | ~0.19% | ~0.20% |
| Fund size | Multi-billion €, growing | One of Europe’s largest, tens of billions € |
| US withholding on dividends | Can be reduced via swap structure | 15% treaty rate withheld inside the fund |
| Main structural risk | Swap counterparty risk (capped, collateralised) | Securities-lending risk (limited, collateralised) |
Treat every number here as approximate and 2026-vintage. Check the current TER and tracking data on each provider’s factsheet, and use the UCITS ETF comparison tool to see them side by side with live figures.
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Tax treatment is the same for you
One point that reassures a lot of readers: because both funds are Irish-domiciled and accumulating, your own tax treatment as a European investor is identical between them. Whether your country taxes accumulating ETFs on realised gains, on a deemed annual basis, or via a wealth-style regime, choosing Invesco or iShares does not change which rules apply. The withholding-tax difference happens inside the fund, so it affects performance rather than your tax return. Confirm your national rules the usual way, and check the exact ISIN and share class on the IWDA factsheet breakdown before you order.
My verdict: which one I would actually buy
If you want the simplest, most bulletproof default, buy the iShares Core MSCI World. It owns real stocks, it is enormous and liquid, it has a long record, and you never have to think about swaps again. For a beginner who wants to set up a savings plan and forget it, this is the answer, and the one I point most people toward.
If you are cost-obsessed and comfortable with how synthetic replication works, the Invesco MSCI World is a legitimate, sometimes cheaper-tracking alternative, thanks to the US withholding edge. I would happily hold it as a core and would not lose sleep over the counterparty risk given the UCITS safeguards. What I would not do is chop and change chasing a few basis points, or hold both and create needless overlap. Pick one structure you understand, and let it compound. My roundup of the best MSCI World ETFs for European investors puts both in context.
For the index rules both funds follow, MSCI publishes the official MSCI World Index, and iShares hosts the live iShares Core MSCI World factsheet with current holdings and tracking data.
Frequently asked questions
Q: Is the Invesco MSCI World ETF safe despite being synthetic?
A: It is a fully regulated UCITS fund with the same investor protections as any physical ETF, including a 10% cap on exposure to any single swap counterparty, multiple counterparties and a marked-to-market collateral basket. The synthetic structure adds a modest counterparty risk rather than a large one, and the fund’s assets are ring-fenced from Invesco as the manager. It is reasonable to hold, provided you understand the trade-off.
Q: Which has the lower fee, Invesco or iShares?
A: They are extremely close, with Invesco typically around 0.19% and iShares around 0.20% as a 2026 illustration. The difference is roughly one euro a year on €10,000, so it should not decide your choice. Verify both figures on the current factsheets, since providers do adjust fees.
Q: Do IWDA, SWDA and EUNL differ from each other?
A: No, they are the same iShares Core MSCI World fund with the same ISIN, simply listed on different exchanges and in different trading currencies. IWDA trades in Amsterdam, SWDA on the London Stock Exchange, and EUNL on Xetra. Buy whichever line matches your account currency to avoid an unnecessary foreign-exchange conversion.
Q: Why does the synthetic Invesco fund sometimes track better?
A: Because a swap-based structure can receive the US portion of the index return with reduced dividend withholding tax, and the US is about 70% of the MSCI World. A physical fund has 15% withheld on those dividends under the tax treaty. That recovered fraction can offset Invesco’s costs and occasionally push its tracking difference below physical rivals, though it is not guaranteed every year.
Q: Are both funds accumulating, and does that affect my tax?
A: Yes, both automatically reinvest dividends inside the fund rather than paying them out. Your tax treatment depends on your country of residence, not on which of these two you choose, since both share the same Irish domicile and accumulating structure. Check your national rules, and speak to a local tax adviser if your situation is complex.
Q: Can I hold both to diversify provider risk?
A: You can, but there is little point because both track the identical index, so you gain no diversification of holdings, only a mix of two replication methods. That mainly adds admin and two sets of spreads. It is cleaner to pick the structure you are comfortable with and concentrate your contributions there.
European UCITS/ETF investor with 11+ years building a global dividend and index portfolio, and founder of Financial Expert Class. I write every guide here from first-hand experience investing across EU brokers and tax regimes — not theory. More about me →