Comparing SPY, VOO, IVV, and CSPX: Understanding Your S&P 500 ETF Options

The S&P 500 isn’t just another stock index. It’s the heartbeat of the U.S. economy, tracking 500 of America’s largest and most influential companies across sectors from technology and healthcare to consumer goods and financials. Think of it as a ready-made, globally diversified portfolio of U.S. corporate giants — Apple, Microsoft, Amazon, JPMorgan, NVIDIA — all in one index.

And history tells a powerful story. Over the past 50 years, the S&P 500 has delivered an average annualised return of about 10%, despite recessions, oil crises, dot-com busts, and even the 2008 financial meltdown. 

A simple buy-and-hold strategy in the S&P 500 has consistently outperformed the majority of actively managed funds. For example, USD 10,000 invested in the S&P 500 in 1980 would be worth more than USD 1 million by 2025, assuming dividends were reinvested. That kind of compounding explains why the index has become a cornerstone for long-term wealth building worldwide.

In today’s climate, the appeal remains strong. With U.S. GDP is expected to grow 1.4% in 2025 and the Federal Reserve poised to ease rates after a tightening cycle, investors are gravitating toward predictable, broad-based exposure.

— The S&P 500 offers just that: low-cost diversification and a proven track record of compounding returns over time.

But here’s the real question: Which S&P 500 ETF should you buy — SPY, VOO, IVV, or CSPX? Each comes with unique differences in cost, liquidity, and tax efficiency that can significantly impact your long-term returns. This guide breaks them down for you, so you can invest smarter, not harder.

The Top 20 S&P 500 ETFs in 2025

At first glance, it might seem redundant to have dozens of ETFs all tracking the same index — the S&P 500. After all, they hold the same basket of U.S. large-cap stocks. But the differences lie in how they’re structured, where they’re domiciled, and what costs are involved.

For investors, these nuances matter:

• Domicile: Determines tax treatment. For example, U.S.-listed ETFs like SPY, VOO, and IVV face a 30% dividend withholding tax for Singapore residents, while Ireland-domiciled UCITS ETFs (like CSPX) reduce that to 15% under tax treaties.
• Total Expense Ratio (TER): Small differences compound over decades. ETFs with 0.03% fees (like VOO, IVV) will almost always outperform those charging 0.09% (SPY), all else equal.
• Liquidity: Traders may prefer highly liquid funds like SPY, while long-term investors often prioritise lower-cost funds like VOO or IVV.
• Fund Size (AUM): Larger funds generally have tighter bid-ask spreads and are less likely to be shut down.

The key takeaway: While the performance differences between S&P 500 ETFs are usually small, the right choice for you depends on your investment horizon, tax situation, and broker access.

* Fund AUM as of Sep 2025

The four heavyweights: SPY, VOO, IVV, and CSPX 

When you decide to invest in the S&P 500 via an ETF, four heavyweight options consistently dominate investor portfolios: SPY, VOO, IVV, and CSPX. Think of them as different airlines flying to the same destination — they’ll all get you U.S. large-cap exposure, but your journey (and cost efficiency) will vary based on the product’s structure, tax treatment, and total expense ratio (TER).

For long-term investors, especially those based in Singapore, these subtle differences can have a multi-thousand — or even multi-million — dollar impact on final portfolio outcomes due to dividend taxation, compounding, and cost drag.

SPDR S&P 500 ETF Trust (SPY)

Key facts:

• Issuer: State Street Global Advisors
• Structure: UIT (Unit Investment Trust)
• Expense ratio: 0.0945%
• AUM: ~$663B
• Dividend handling: Distributing
• Liquidity: Highest (70M+ shares traded daily)

Summary:
Launched in 1993, SPY is the oldest and most traded ETF in the world — the original S&P 500 tracker. Its unparalleled liquidity and tight bid-ask spreads make it the go-to choice for institutional traders, hedge funds, and investors running options strategies.

However, its UIT structure means dividends cannot be automatically reinvested, which creates slight performance drag versus modern ETFs like VOO or IVV. For long-term buy-and-hold investors, SPY is often considered less cost-efficient than its peers.

Vanguard S&P 500 ETF (VOO)

Key facts:

• Issuer: Vanguard
• Structure: ETF (Open-end Fund)
• Expense ratio: 0.03%
• AUM: ~$746B
• Dividend handling: Distributing
• Liquidity: High (6.8M shares daily)

Summary:

VOO is Vanguard’s low-cost flagship S&P 500 ETF, launched in 2010 as a modern, more efficient alternative to SPY. It uses an open-end ETF structure that allows for internal dividend reinvestment, resulting in slightly better tracking performance over time.

Its biggest draw is its ultra-low 0.03% expense ratio, making it one of the cheapest ways to own the entire S&P 500. This cost advantage, combined with Vanguard’s investor-owned structure, has made VOO the preferred choice for long-term, buy-and-hold investors.

In fact, by 2025, VOO has overtaken SPY as the largest S&P 500 ETF by assets under management (AUM) — a sign that more investors are prioritizing cost efficiency and compounding over short-term trading liquidity.

iShares Core S&P 500 ETF (IVV)

Key facts:

• Issuer: BlackRock iShares
• Structure: ETF (Open-end Fund)
• Expense ratio: 0.03%
• AUM: ~$660B
• Dividend handling: Distributing
• Liquidity: High (5.6M shares daily)

Summary:

IVV is BlackRock’s answer to VOO, offering identical low fees (0.03%), physical replication, and efficient dividend reinvestment. It is deeply integrated into the iShares ecosystem, making it a favourite among large institutions and model portfolios built on BlackRock’s Aladdin platform.

Functionally, IVV and VOO are nearly interchangeable. Choosing between them often comes down to broker availability or investor preference for Vanguard vs iShares.

iShares Core S&P 500 UCITS ETF (CSPX)

Key facts:

• Issuer: BlackRock (Ireland)
• Structure: UCITS ETF (Physical replication)
• Expense ratio: 0.07%
• AUM: ~$132B
• Dividend handling: Accumulating (reinvested)
• Liquidity: Moderate (109k daily volume on LSE)

Summary:

CSPX is the go-to S&P 500 ETF for international investors, especially those in Singapore. Its Ireland domicile gives it a major tax edge — dividends are subject to only 15% withholding tax at the fund level (versus 30% for U.S.-domiciled ETFs). And because it is accumulating, dividends are automatically reinvested, creating superior long-term compounding.

Although its expense ratio (0.07%) is slightly higher and liquidity is lower than U.S.-listed ETFs, these disadvantages are dwarfed by the tax savings over time.

Comparing SPY, VOO, IVV, and CSPX

While these four ETFs may track the same index, their structural and tax differences lead to significantly different outcomes — especially for non-U.S. investors.

Below is a side-by-side comparison updated for September 2025:

* data as of 10th Sep 2025

What this means for investors

For short-term traders, SPY remains unmatched in liquidity. But for long-term investors, CSPX is often the superior choice due to its tax-efficient structure and compounding features.

Even though its expense ratio is slightly higher (0.07%), the 15% dividend withholding rate vs. 30% on U.S.-listed funds more than offsets the cost difference over time. And because CSPX is accumulating, you won’t receive taxable dividends into your cash account — everything is reinvested, helping you stay hands-off and growth-focused.

Meanwhile, VOO and IVV remain best-in-class for U.S.-domiciled options if you're investing through tax-advantaged accounts like U.S. IRAs — or if you're prioritising ultra-low costs and receiving your dividends elsewhere.

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Fees and tax deep dive for investors

Tax and fee structure can quietly erode your returns over time — or, if managed smartly, supercharge your compounding.

And the biggest variable isn’t performance, timing, or even risk appetite. It’s where your ETF is domiciled.

1. The dividend withholding tax trap

Let’s start with the single biggest tax drag Singaporeans face when investing in U.S. equities: the 30% dividend withholding tax.

Because Singapore has no tax treaty with the U.S., any dividends paid out by U.S.-listed ETFs (like SPY, VOO, IVV) are subject to this flat 30% tax. That means nearly a third of your dividends are withheld by the IRS before you even see a cent.

Example:

• S&P 500 dividend yield: 1.5%
• Investment: S$100,000
• Gross dividends: S$1,500/year
• Withholding tax (30%): S$450
• Net dividends received: S$1,050

That’s money you never see. And over 10, 20, 30 years, this "tax drag" significantly reduces your compounding returns.

2. The UCITS advantage: How CSPX saves you money

This is where Ireland-domiciled ETFs like CSPX become a game-changer. Thanks to a U.S.–Ireland tax treaty, ETFs domiciled in Ireland pay only 15% withholding tax on U.S. dividends.

But CSPX goes a step further — it’s an accumulating ETF. This means it doesn’t distribute dividends at all. Instead, any net dividends left after the 15% tax are automatically reinvested inside the fund, before reaching your account.

Using the same example:

• Gross dividends: S$1,500
• Withholding tax (15%): S$225 (applied inside the fund)
• Reinvested automatically: S$1,275

You pay no further taxes on these reinvested dividends, and you benefit from full compounding, tax-efficient growth.

Compared to VOO, which pays out S$1,050 in taxed dividends, CSPX keeps S$1,275 working inside your portfolio — a difference of S$225 every year, or thousands over time.

3. U.S. estate tax

Beyond annual dividends, there’s another tax most Singapore investors never see coming: the U.S. estate tax.

If you hold more than US$60,000 in U.S.-sited assets (like SPY, VOO, or IVV) at the time of your death, your heirs could be subject to estate taxes of up to 40%. This applies even if you're not a U.S. citizen or resident.

That’s right — your legacy could be taxed just because your ETFs are listed in the U.S.

By contrast, UCITS ETFs like CSPX are not considered U.S.-sited assets. Holding CSPX legally and cleanly avoids U.S. estate tax exposure, providing peace of mind for high-net-worth individuals and long-term investors.

4. Brokerage and FX costs

While fund-level taxes get the spotlight, your broker choice also matters. Trading costs, currency conversion spreads, and platform fees can quietly eat into your returns.

Here’s a breakdown of the most relevant platforms for Singapore-based investors buying U.S. or Ireland-listed ETFs in 2025:

5. Beyond commissions: The hidden costs

1. FX spreads
   When you convert SGD to USD (or GBP for CSPX), brokers typically charge an FX spread of 0.30%–0.70% above interbank rates. This fee isn’t always visible, but it’s real.  
2. Custody and platform fees
   Some banks (like DBS Vickers) may charge custody fees (e.g., S$2 per stock per quarter). Most modern brokers (Moomoo, Tiger) do not.  
   
3. Fund-level expense ratio (TER)
   You also pay internal fund fees — VOO and IVV are cheapest at 0.03%, SPY is higher at 0.09%, while CSPX sits at 0.07%. Though minor, these differences compound over decades.  

Understanding distribution and replication in S&P 500 ETFs

When evaluating S&P 500 ETFs like SPY, VOO, IVV, or CSPX, investors often come across terms like “accumulating vs distributing” and “replication method.” These aren't just technical distinctions — they directly affect how you receive returns, how your investment compounds, and how efficiently your ETF tracks the index.

A. Distribution: Accumulating vs distributing

This describes how the ETF handles dividends paid by the companies in the S&P 500.

S&P 500 ETF examples:

• Distributing: SPY, VOO, IVV
• Accumulating: CSPX (iShares Core S&P 500 UCITS ETF)

Accumulating ETFs like CSPX are more tax-efficient for Singapore investors. You avoid unnecessary dividend withholding taxes and benefit from automatic reinvestment.

B. Replication method: Full vs swap-based (synthetic)

This refers to how the ETF replicates the performance of the S&P 500 index — either by holding the stocks directly or using derivative contracts.

What investors should know:

• Most mainstream S&P 500 ETFs use full replication, including CSPX.
• Unfunded swap-based ETFs exist in Europe, but are rarely used for S&P 500 exposure unless you're accessing niche synthetic UCITS products.

Summary: What to choose

Understanding these mechanics ensures you're not just picking any ETF, but selecting one that’s optimised for your residency, goals, and long-term compounding efficiency.

Performance: Do returns really differ?

A common question investors ask is: If all these ETFs track the same index, won’t they all deliver the same returns?

At first glance, the answer is yes — on a gross basis, SPY, VOO, IVV, and CSPX have nearly identical performance. But the reality is more nuanced. Once you factor in fees and taxes, your net, take-home return — the only number that truly matters — can diverge meaningfully over time.

They all track the same 500 companies

The S&P 500 index includes household names like Apple, Microsoft, Amazon, Nvidia, and JPMorgan. All four ETFs — SPY, VOO, IVV, and CSPX — aim to replicate this exact basket of stocks as closely as possible.

If you were to plot their 10-year total return charts, the lines would appear almost indistinguishable. This isn’t a coincidence — it’s because they all follow the same benchmark with near-perfect accuracy.

But let’s break down the subtle forces that cause small differences in performance over time:

1. Tracking error

This measures how closely an ETF mirrors its benchmark. All four ETFs have exceptionally low tracking error, typically under 0.05% annually. That’s a rounding error — and a testament to their fund managers' operational efficiency.

2. Fee drag

Fees may look tiny, but they’re guaranteed and ongoing.

• VOO and IVV charge just 0.03%
• SPY charges 0.09%
• CSPX sits at 0.07%

On a S$100,000 portfolio, that’s the difference between paying S$30 or S$90 a year. Over time, this matters — but not nearly as much as tax.

3. Tax drag

This is where the real difference emerges, especially for Singaporean investors.

• U.S.-domiciled ETFs like SPY, VOO, and IVV suffer a 30% dividend withholding tax
• CSPX, domiciled in Ireland, benefits from a 15% treaty rate, and reinvests dividends internally

The result? CSPX retains more of the S&P 500’s yield, and automatically compounds it back into the fund without distributing taxable cash to you.

Same engine, different fuel efficiency

Think of SPY, VOO, IVV, and CSPX as four identical race cars — all equipped with the same engine (the S&P 500). The only difference is how much friction each one faces:

Over a 30-year horizon, that lower dividend tax and automatic reinvestment give CSPX a clear compounding edge — often outperforming its U.S.-domiciled peers despite having a slightly higher TER.

How to buy S&P 500 ETFs in Singapore (step-by-step)

Buying your first S&P 500 ETF is simple — but choosing the right platform can significantly affect your long-term returns. Whether you're buying CSPX via a broker or using a robo-advisor, here’s a streamlined guide to get started.

Step 1: Choose your platform

You have three main options:

A. Global brokers

Ideal for long-term, cost-conscious investors.

• Interactive Brokers (IBKR): Tight FX spreads (~0.002%), low commissions, access to CSPX (LSE).
• Saxo Markets: Clean interface, higher platform and FX fees.
• Moomoo SG / Tiger Brokers: Beginner-friendly, low minimums, access to U.S. and LSE-listed ETFs.

Interactive Brokers (IBKR): 

B. Local bank brokers

Bank-linked platforms like DBS Vickers, OCBC Securities, UOB Kay Hian offer convenience since they are directly linked to a bank, but charge higher fees and FX spreads. Suitable if you prioritise banking integration over cost efficiency.

C. Robo-advisors

For a fully automated experience, StashAway allows direct allocation to the S&P 500 through its Flexible Portfolios, giving you control over exposure without managing execution or FX.

• Platform fee: 0.30% (if single asset class)
• No trading, currency conversion, or custody hassle
• Ideal for hands-off investors who still want targeted ETF access

Step 2: Open and fund your account

Once you've chosen a platform, create your account by completing the online application process. Most platforms approve within 1–2 business days.

You’ll then fund your account using FAST transfer from your local bank (e.g., DBS, UOB, OCBC). Robo-advisors typically allow eGIRO or PayNow as well.

Step 3: Convert your currency

Most S&P 500 ETFs, including CSPX, are traded in USD (CSPX also has a GBP version, but USD is more liquid).

• Brokers allow you to convert SGD to USD before placing your order.
• Some platforms offer conversion at interbank-like rates (e.g., IBKR), while others charge wider FX spreads (up to 0.70%).
• Robo-advisors handle this automatically, though the FX spread is baked into the platform's operations.

Step 4: Search and place your order

Once your funds are in USD:

1. Search for the ETF by ticker — e.g., CSPX on the London Stock Exchange.
2. Select the correct exchange — CSPX is listed on LSE (USD). Don’t confuse this with similarly named tickers.
3. Place a limit order — Set the maximum price you're willing to pay. This is crucial for less-liquid ETFs like CSPX, especially outside London trading hours.

Avoid market orders unless you are trading during peak LSE hours and see a tight bid-ask spread.

Step 5: Monitor and hold long-term

Once your trade is filled:

• Track your portfolio performance, not just price.
• Be aware of ongoing platform fees, FX costs for future top-ups, and the fund’s internal expense ratio (e.g., CSPX = 0.07%).

Remember, the S&P 500 is a long-term asset — resist the temptation to trade based on short-term noise.

Alternatives to S&P 500 ETFs

While S&P 500 ETFs are a core building block in many global portfolios, they’re not the only option. Depending on your investment goals—whether you’re seeking short-term stability, income, or thematic growth—there are other ETF strategies and low-risk instruments that may be more appropriate for your needs.

Here are two broad categories to consider: money market funds and alternative equity ETFs.

A. Money market funds: for safety and liquidity

Money market funds are ideal for investors who prioritise capital preservation, liquidity, and short-term yield. They invest in high-quality, short-duration debt instruments such as Treasury bills, commercial paper, and bank deposits. Unlike S&P 500 ETFs, they don’t expose you to equity market volatility.

They’ve become especially attractive in 2025 as short-term interest rates remain elevated, with several SGD-denominated MMFs offering yields between 1.8% and 3.0%, depending on the provider and product risk profile.

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B. Other equity ETFs: for growth and diversification

If you’re already invested in the S&P 500 or want to broaden your equity exposure, consider equity ETFs that offer global diversification, sector focus, or alternative income strategies. These ETFs allow you to tailor your portfolio based on your views, goals, or desired risk profile.

Popular options include international ETFs, emerging markets, tech-focused themes, and dividend-paying equity funds. Many of these are listed on the same U.S. or European exchanges as the S&P 500 ETFs and offer similar cost structures and liquidity.

FAQs

Is VOO better than SPY?

Yes — for long-term investors, VOO is more cost-efficient with a lower expense ratio (0.03% vs 0.09%) and better dividend handling. But if you're in Singapore, CSPX is often better due to tax advantages.

Which S&P 500 ETF is best for Singapore investors?

CSPX is generally the best choice. It’s Ireland-domiciled, enjoys a 15% dividend withholding tax rate, and avoids U.S. estate tax — making it more efficient for non-U.S. investors.

Can I buy CSPX in SGD?

No. CSPX trades in USD or GBP on the London Stock Exchange (LSE). You’ll need to convert SGD into one of those currencies before purchasing it via your broker.

Do all S&P 500 ETFs have the same performance?

Gross returns are nearly identical, but net returns differ due to fees and dividend taxes. CSPX often outperforms over time due to lower tax drag and internal reinvestment.

What's the cheapest way to buy an S&P 500 ETF in Singapore?

Use Interactive Brokers (IBKR) or another low-cost broker with tight FX spreads. Avoid high-fee bank platforms or products with wide currency conversion margins.

Is CSPX risky due to lower liquidity?

CSPX has lower daily trading volume than SPY, but it's a large, liquid fund. Use limit orders, especially outside London trading hours, to avoid bad fills.

Will I get dividends from CSPX?

No — CSPX is an accumulating ETF. Dividends are reinvested internally, which boosts long-term compounding and reduces immediate tax liability.