IWDA is BlackRock's iShares Core MSCI World UCITS ETF. As an Ireland domiciled, accumulating fund with about $151 billion in assets (as of October 2026), it is a highly liquid and widely utilized ETF designed to track the MSCI World Index for broad equity exposure across 23 developed markets.
IUSQ is BlackRock's iShares MSCI ACWI UCITS ETF. It shares the exact same 0.20% Total Expense Ratio and the same accumulating structure, but tracks the MSCI All Country World Index to provide comprehensive exposure across both developed and emerging markets, holding about $36 billion in assets (as of October 2026).
Investors are often confused between these two because they are both broad global equity funds from the same provider that cost exactly the same on paper. Here is how and where their underlying portfolios differ, and which one makes more sense as the anchor for your long-term investment strategy.
| Feature | IWDA | IUSQ |
|---|---|---|
| Provider | iShares (BlackRock) | iShares (BlackRock) |
| Index | MSCI World Index | MSCI ACWI |
| TER | 0.20% | 0.20% |
| Tracking difference (2025) | +0.1% | +0.1% |
| AUM | ~$151B (Oct 2026) | ~$36B (Oct 2026) |
| Launched | September 25, 2009 | October 21, 2011 |
| Replication | Physical (optimised sampling) | Physical (optimised sampling) |
| Domicile | Ireland | Ireland |
| Structure | Accumulating | Accumulating |
| ISIN | IE00B4L5Y983 | IE00B6R52259 |
Tracking difference in the table is the fund's 2025 calendar-year return minus its index's return, as published by the issuer. A negative figure means the fund lagged its index.
Table of contents
- What IWDA and IUSQ have in common
- Where they differ
- Which should Indian investors buy?
- Already holding one? Should you switch?
What IWDA and IUSQ have in common
- Both are managed by BlackRock under the iShares brand and carry the same 0.20% Total Expense Ratio.
- Both use physical optimized sampling to replicate their indices and are heavily weighted in US mega-cap technology stocks like Apple, Microsoft, NVIDIA, Amazon, and Meta.
- Both are Ireland domiciled. This eliminates the 40% US estate tax risk for Indian investors and leverages the US-Ireland tax treaty to reduce the withholding tax on US dividends from 30% to 15%.
- Both are accumulating funds, meaning dividends are automatically reinvested internally to maximize long-term compounding without creating an annual taxable event.
- Both share the same Indian tax treatment: Short-Term Capital Gains (STCG) at your applicable slab rate if held for 24 months or less, and Long-Term Capital Gains (LTCG) at 12.5% if held for more than 24 months.
- Both are readily available on global platforms like Interactive Brokers and Paasa.
Where they differ
Index exposure and emerging markets
The most significant difference lies in their geographic mandates. IWDA tracks the MSCI World Index, which exclusively covers 23 developed markets. The fund holds about 1,250 stocks (as of October 2026) and is heavily concentrated in the United States, carrying a US weighting of over 70%.
IUSQ tracks the MSCI All Country World Index (ACWI), which covers about 85% of the investable equity market in each of 23 developed and 24 emerging markets. Because of this emerging market inclusion, IUSQ holds a broader basket of about 1,665 stocks (as of October 2026), and its US concentration is slightly diluted to roughly 63%.
Fund size and ticker variations
IWDA launched in 2009 and currently holds about $151 billion in assets, making it roughly four times larger than IUSQ. While both ETFs are highly liquid cornerstones for any portfolio, IWDA's massive size and longer history provide exceptionally tight bid-ask spreads for large execution orders.
Additionally, while IWDA is the globally recognized ticker for the developed world fund, IUSQ goes by different names depending on the exchange. IUSQ is the ticker used on European exchanges like Xetra in Germany. On the London Stock Exchange (LSE), the same fund trades as ISAC in USD and SSAC in GBP.
Tracking difference and index variants
While both funds charge a 0.20% TER, both beat the Net Return version of their benchmarks. The MSCI Net Return indices assume that the maximum withholding tax applicable to non-resident institutional investors is paid on dividends in each country, which for US dividends is 30%.
These Irish-domiciled ETFs pay only the 15% treaty rate on US dividends, and BlackRock earns extra revenue through securities lending. Together, these offset the funds' management fees.
In 2025 IWDA returned 21.2% against 21.1% for its index, and IUSQ returned 22.4% against 22.3% for its index, so both beat their benchmarks by about 0.1 percentage points.
Performance drivers and replication costs
Because IUSQ includes 24 emerging markets, buying every single small, illiquid global stock would be prohibitively expensive. BlackRock uses an optimized sampling technique for both funds, but this is particularly crucial for IUSQ to manage transaction costs while keeping tracking error minimal.
Over the last five years, performance for both funds has been driven almost entirely by the US technology sector. The emerging market allocation in IUSQ acts as a diversifier, but it has served as a slight drag on aggregate performance compared to the pure developed market focus of IWDA.
Which should Indian investors buy?
For investors seeking a one-stop, single-ticker solution for global equity exposure, IUSQ is the superior choice. It naturally rebalances between developed and emerging markets based on global market capitalization, capturing the entire investable world without requiring any manual adjustments on your part.
You should pick IWDA if you prefer absolute control over your portfolio's geographic allocations. By holding IWDA, you secure a highly efficient, liquid anchor of developed markets. This gives you the freedom to either avoid emerging markets entirely or add a separate emerging market ETF at a specific weight of your own choosing.
Ultimately, do not overthink it. Both are top-tier, highly efficient vehicles for building long-term wealth. Whether you choose the built-in global diversification of IUSQ or the targeted developed market focus of IWDA, picking either one puts you on the right path.
Already holding one? Should you switch?
If you already hold IWDA or IUSQ, do not sell your position just to switch to the other. Selling your shares triggers a capital gains event in India. If you have held the ETF for 24 months or less, you will pay STCG at your slab rate. If you have held it for more than 24 months, you will pay LTCG at 12.5%.
The structural differences between the two are not large enough to justify the taxes you will pay on the sale and the brokerage fees required to switch. If you currently hold IWDA and decide you want emerging market exposure, simply purchase a dedicated emerging market ETF alongside it, or direct all future investments into IUSQ while leaving your existing shares alone.
Building your portfolio with Ireland-domiciled UCITS ETFs is a tax-efficient way for Indian investors to access global markets. You can read our complete LRS guide to learn how to fund your global account seamlessly.
Compare more: VWCE vs IUSQ, VWCE vs IWDA.
Related: What are UCITS ETFs? and Top UCITS ETFs for Indian investors
About Paasa
Paasa is a global investing platform for Indian residents and NRIs, with access to stocks and ETFs across 11 markets: the US, Canada, the UK, Germany, France, Switzerland, the Netherlands, South Korea, Japan, Hong Kong and Singapore.
- Estate Tax Protection: Paasa gives you direct access to Ireland-domiciled (UCITS) ETFs, including IWDA and IUSQ. This allows you to legally shield your long-term wealth from the 40% US Estate Tax.
- Seamless Funding & LRS: We handle the LRS compliance process and secure competitive FX rates, ensuring your capital reaches the global markets efficiently.
- The Compliance Advantage: We generate ready-made capital gains and Schedule FA tax reports tailored for the Indian tax system, so you can focus entirely on growing your portfolio instead of managing spreadsheets.
