CSPX is BlackRock's iShares Core S&P 500 UCITS ETF. As an Ireland-domiciled, accumulating fund with about $157 billion in assets (as of October 2026), it is a highly efficient and liquid vehicle available to Indian investors seeking long-term U.S. large-cap market exposure.
IWDA is BlackRock's iShares Core MSCI World UCITS ETF. As a globally diversified fund tracking 23 developed markets, it manages about $151 billion in assets (as of October 2026) and serves as a foundational building block for investors seeking broad international exposure.
Indian investors are often confused between these two because both are highly popular, Ireland-domiciled iShares ETFs that hold a significant amount of US stocks. Here is how and where they differ, and which one makes more sense for Indian investors.
| Feature | CSPX | IWDA |
|---|---|---|
| Provider | iShares (BlackRock) | iShares (BlackRock) |
| Index | S&P 500 Index | MSCI World Index |
| TER | 0.07% | 0.20% |
| Tracking difference (2025) | +0.2% | +0.1% |
| AUM | ~$157B (Oct 2026) | ~$151B (Oct 2026) |
| Launched | 2010 | 2009 |
| Replication | Physical (full) | Physical (optimised sampling) |
| Domicile | Ireland | Ireland |
| Structure | Accumulating | Accumulating |
| ISIN | IE00B5BMR087 | IE00B4L5Y983 |
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 CSPX and IWDA have in common
- Where they differ
- Which should Indian investors buy?
- Already holding one? Should you switch?
What CSPX and IWDA have in common
- Ireland-Domiciled: For U.S. holdings, this reduces the dividend withholding tax rate from 30% to 15% via the U.S.-Ireland treaty. It also eliminates the 40% U.S. estate tax risk for Indian residents.
- UCITS Framework: Both follow strict European regulatory standards regarding risk management and asset segregation.
- Accumulating Structure: Dividends are automatically reinvested, removing immediate tax liabilities on yield and maximizing compounding.
- Indian Taxation: Both treated as foreign assets: STCG at slab rates (24 months or less) and LTCG at 12.5% (more than 24 months).
- Accessibility: Readily available on global platforms like Interactive Brokers and Paasa.
Where they differ
Index, sector focus, and fund size
CSPX tracks the S&P 500, capturing ~80% of the U.S. market cap. It is heavily tech-leaning (Apple, NVIDIA, Microsoft). With about $157 billion in assets, it offers massive institutional-grade liquidity and paper-thin bid-ask spreads.
IWDA tracks the MSCI World Index (23 developed markets). While U.S.-heavy (~70%), it includes exposure to Japan, Europe, and Canada. With about $151 billion in assets, it provides a broader geographical footprint in a single ticker.
Tracking difference and expenses
While the headline TER favors CSPX (0.07% vs 0.20%), tracking difference shows what you actually earn against the index. Securities lending income and the 15% treaty rate on US dividends helped both funds beat their net indices in 2025.
- CSPX: Returned 17.6% in 2025 against 17.4% for the S&P 500 net index, a tracking difference of +0.2%.
- IWDA: Returned 21.2% in 2025 against 21.1% for the MSCI World net index, a tracking difference of +0.1%, despite its higher TER.
Which should Indian investors buy?
If you want the tightest possible execution and pure exposure to the engine of the U.S. economy, CSPX is the definitive choice. Its 0.07% TER and massive scale make it one of the most efficient wealth-building tools available.
If you prefer geographical diversification beyond just the U.S. to mitigate single-country risk, IWDA is the superior foundational block. You sacrifice a small amount of cost efficiency for broader exposure across the developed world.
Already holding one? Should you switch?
Short answer: No. Selling your current holdings triggers an immediate tax event in India. The friction of paying 12.5% LTCG or slab-rate STCG will instantly erase the marginal benefit of a lower TER or a different index. If you wish to pivot, simply keep your existing shares and direct new capital into the other fund.
Building your portfolio with Ireland-domiciled UCITS ETFs is a tax-efficient way for Indian investors to access global markets.
Compare more: CSPX vs VWCE, QQQ vs CSPX.
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: Direct access to Ireland-domiciled (UCITS) ETFs to shield wealth from the 40% U.S. Estate Tax.
- Seamless Funding: We handle LRS compliance and provide competitive FX rates.
- The Compliance Advantage: Ready-made capital gains and Schedule FA tax reports tailored for the Indian tax system.
