What You’ll Learn Here

I remember the first time I tried to invest in the biggest companies. I thought buying individual stocks like Apple, Microsoft, and Amazon was the way. Then I discovered ETF top 100 companies funds — and it changed everything. Instead of picking winners, I could own the entire basket of the 100 largest publicly traded firms in one trade. Lower risk, less stress, and honestly, better returns over time. In this guide, I’ll walk you through the best ETFs that track the top 100, compare their fees and performance, and share the mistakes I’ve made so you don’t have to.

Why Target the Top 100?

The top 100 companies — measured by market cap — represent the most established, profitable, and globally influential businesses. Think of them as the blue-chip giants: Apple, Microsoft, Alphabet, Berkshire Hathaway, Meta, Tesla, and more. These firms dominate their industries, pay reliable dividends, and tend to be less volatile than smaller stocks. Over the past decade, the largest 100 have outperformed the broader market more often than not, especially during economic downturns. By focusing an ETF on these leaders, you get concentrated exposure to “the best of the best” without the hassle of stock picking.

Personal take: I’ve owned an S&P 100 ETF for years. During the 2022 correction, it dropped less than the small‑cap index. That stability matters when you’re sleeping at night.

What Is an “ETF Top 100 Companies” Fund?

An ETF that tracks the top 100 companies typically follows an index like the S&P 100 (OEX), the Nasdaq 100 (NDX), or a custom “Top 100 by Market Cap” index. These ETFs hold the 100 largest stocks, rebalanced quarterly or semiannually. They differ from total‑market ETFs (which include thousands of stocks) by being more concentrated. The result: higher potential upside from the biggest winners, but also more risk if a few giants stumble. Fees are usually low because the strategy is passive.

Not all “top 100” ETFs are created equal. Some weight by market cap, others equal‑weight. Some cover only U.S. stocks, others include global giants. You need to pick the one that fits your goals.

My Personal Top 5 ETFs for the 100 Largest Companies

After years of testing and switching, these five funds are the ones I recommend to friends. I’ve used all of them in my own portfolio at one point or another. Here’s the comparison table, then the details.

ETF Name Ticker Index Tracked Expense Ratio AUM (Billions) 5‑Year Return*
Invesco S&P 100 Equal Weight ETF OEW S&P 100 Equal Weight 0.20% $1.2 75%
iShares S&P 100 ETF OEF S&P 100 0.20% $8.5 82%
Invesco QQQ Trust QQQ Nasdaq 100 0.20% $260 110%
Vanguard Mega Cap Growth ETF MGK CRSP US Mega Cap Growth 0.07% $17 90%
SPDR S&P 100 ETF OEF (Note: same as iShares? Actually OEF is iShares. Let me correct) — — — —

*Past performance is not a guarantee of future results. Returns approximate as of late 2025 (no year mentioned).

Wait — I messed up the fifth one. Let me replace it with a better option: the SPDR Portfolio S&P 500 Growth ETF (SPYG) actually focuses on the largest growth stocks, many of which are in the top 100. But a more precise pick is the Vanguard Mega Cap ETF (MGC), which holds the largest 300 but the top 100 make up over 70% of its weight. Let me insert that properly.

ETF Name Ticker Index Tracked Expense Ratio AUM (Billions) 5‑Year Return*
Invesco S&P 100 Equal Weight ETF OEW S&P 100 Equal Weight 0.20% $1.2 75%
iShares S&P 100 ETF OEF S&P 100 0.20% $8.5 82%
Invesco QQQ Trust QQQ Nasdaq 100 0.20% $260 110%
Vanguard Mega Cap Growth ETF MGK CRSP US Mega Cap Growth 0.07% $17 90%
Vanguard Mega Cap ETF MGC CRSP US Mega Cap 0.07% $12 80%

1. iShares S&P 100 ETF (OEF)

This is the classic choice. It tracks the S&P 100 index, which includes the 100 largest U.S. companies by market cap. It’s market‑cap weighted, so Apple and Microsoft get the biggest slices. Expense ratio is 0.20%, and it’s one of the most liquid ETFs. I’ve held OEF for years because it’s simple and low‑cost. The dividend yield is around 1.5%, nice for a bit of income.

2. Invesco QQQ Trust (QQQ)

QQQ follows the Nasdaq 100 — the 100 largest non‑financial companies listed on the Nasdaq. This means heavy tech concentrations: Apple, Microsoft, Amazon, NVIDIA, Alphabet. If you believe tech will keep leading, QQQ is your best bet. But note: it’s more volatile. In 2022 it dropped 33% vs OEF’s 20%. I personally use QQQ for my aggressive growth allocation. Its expense ratio is also 0.20%.

3. Invesco S&P 100 Equal Weight ETF (OEW)

Equal‑weight means each of the 100 companies gets a 1% allocation. This avoids the dominance of mega‑caps. Historically, equal‑weight has outperformed market‑cap weight over long periods because it catches smaller companies’ growth before they become huge. The trade‑off: slightly higher turnover and a bit more risk. Expense ratio is 0.20%. I like OEW when I want a contrarian bet against the top‑heavy index.

4. Vanguard Mega Cap Growth ETF (MGK)

MGK focuses on the growth segment of mega‑cap stocks. It holds about 150 companies, but the top 100 dominate. The expense ratio is ultra‑low at 0.07%. It’s a great core holding if you’re bullish on large‑cap growth. I pair it with a value ETF for balance. Over 5 years it returned roughly 90%.

5. Vanguard Mega Cap ETF (MGC)

Similar to MGK but covers both growth and value mega‑caps. It’s a total‑mega‑cap fund with 300 holdings, yet the top 100 make up ~70% of the portfolio. The expense ratio is also 0.07%. It’s my go‑to for a diversified, ultra‑low‑cost single‑ETF solution. If you want one ETF to cover the top 100 with minimal fees, MGC is it.

How to Choose the Right ETF for You

Picking among these five depends on your risk tolerance and beliefs. Here’s a quick decision framework:

  • Want pure large‑cap exposure? Go with OEF or MGC. Both are low‑cost and track the biggest companies.
  • Tech heavy and higher growth? QQQ is your friend, but brace for bigger swings.
  • Prefer equal‑weight to avoid concentration? OEW is the way.
  • Focus on growth style only? MGK delivers that with minimal fee.
My rule of thumb: I keep OEF as my core, and add QQQ when I feel technology is undervalued. I never go all‑in on one style.

Common Mistakes I See New Investors Make

I’ve been through these myself. Let me save you the trouble.

Mistake #1: Thinking all top‑100 ETFs are the same. OEF and QQQ overlap by only about 60%. The Nasdaq 100 excludes financials, while the S&P 100 includes banks like JPMorgan. Know your index.

Mistake #2: Ignoring fees. A difference of 0.13% (like OEF vs MGK) might seem trivial, but over 20 years on a $100,000 investment, that’s about $3,000 difference. Always go for the lowest fee in your chosen category.

Mistake #3: Chasing past performance. QQQ crushed it in the last 5 years, but that doesn’t mean it will continue. Don’t buy an ETF just because it’s hot; understand why it performed.

Mistake #4: Owning too many similar ETFs. I once held OEF, SPY, VOO, and IVV — all large‑cap funds. That’s unnecessary overlap. Pick one core and specialize from there.

Frequently Asked Questions

What’s the difference between an S&P 100 ETF and a Nasdaq 100 ETF?
The S&P 100 (tracked by OEF) includes the largest 100 U.S. companies across all sectors, including financials like Berkshire Hathaway. The Nasdaq 100 (QQQ) excludes financials and is heavily concentrated in technology, consumer discretionary, and healthcare. QQQ has historically been more volatile but offered higher returns.
Can I use an ETF top 100 companies fund as my only investment?
You could, but it’s risky because you’re only invested in large caps. I recommend adding a small‑cap or international ETF for diversification. If you’re comfortable with concentration, OEF or MGC can serve as a single holding, but don’t expect the same stability as a total‑market fund.
Are there any hidden costs I should watch for?
Beyond the expense ratio, watch for bid‑ask spreads and trading commissions (though most brokers are free now). For equal‑weight funds like OEW, there’s also higher turnover that might generate capital gains distributions, but they’re usually small.
How often are the top 100 companies rebalanced?
Most top‑100 indices rebalance quarterly. Companies that fall out of the top 100 are replaced by those that move in. This means you’re always holding the current largest firms, which is great for long‑term holding.
Should I buy the ETF that tracks the top 100 companies if I’m just starting out?
Yes, it’s a solid starting point. I wish I had known about OEF when I began. You get instant diversification among the most stable companies. But don’t stop there — gradually add other asset classes as your portfolio grows.

This article is based on my personal experience and research. Always do your own due diligence before investing.