VOO and MGK Both Offer Large-Cap Exposure, But Vary on Risk Profiles, Fees, and Diversification

The Vanguard Mega Cap Growth ETF (NYSEMKT:MGK) and the Vanguard S&P 500 ETF (NYSEMKT:VOO) differ most in their sector concentrations, dividend yields, and long-term risk-return profiles.

Both MGK and VOO are Vanguard funds, but MGK zeroes in on the largest U.S. growth stocks, while VOO tracks the full S&P 500 -- offering exposure to a broader array of top U.S. companies. This comparison spotlights key differences in cost, performance, risk, and portfolio makeup.

Snapshot (cost & size)

Beta measures price volatility relative to the S&P 500. The 1-yr return represents total return over the trailing 12 months.

VOO is more affordable with its lower expense ratio and stands out for its higher dividend yield, offering a larger payout than MGK for income-focused investors.

Performance & risk comparison

What's inside

VOO holds 504 stocks, representing the S&P 500 Index. Its sector mix is broad, led by technology at 36%, followed by financial services at 13% and consumer cyclical at 11%. The top holdings -- Nvidia, Apple, and Microsoft -- each make up less than 10% of the fund, so no single stock dominates. The fund's enormous scale and diversified approach may appeal to those seeking exposure across the full U.S. equity landscape.

MGK, by contrast, is far more concentrated. Its 66 holdings are heavily weighted toward technology (69%), with smaller allocations to consumer cyclical (16%) and healthcare (5%). Its largest holdings mirror VOO, but with higher allocations. This tilt brings higher growth potential but also greater volatility and risk compared to VOO's broader portfolio.

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Foolish take

MGK and VOO both offer exposure to the largest U.S. stocks, but MGK has a much more targeted focus on mega-cap companies.

MGK's significant focus on tech stocks can result in greater gains during tech rallies (as evidenced by its higher one- and five-year returns compared to VOO), but it can also lead to more substantial volatility. With far fewer holdings, this ETF is less diversified, too -- which can increase risk.

VOO, on the other hand, offers far more variety. While it's also heavily weighted toward tech with the same top holdings as MGK, it contains far more stocks with more exposure to other industries. Also, while MGK only includes mega-cap stocks, VOO holds both large- and mega-cap companies.

Where you might choose to invest will depend mainly on your goals. If you're looking specifically for access to mega-cap stocks, MGK can provide targeted exposure to that slice of the market. For a more diversified approach, VOO's access to the S&P 500 can provide broad-market stability.

Glossary

ETF: Exchange-traded fund; a pooled investment fund traded on stock exchanges like a stock.
Expense ratio: The annual fee, as a percentage of assets, that a fund charges its investors.
Dividend yield: Annual dividends paid by a fund or stock divided by its current price, expressed as a percentage.
Beta: A measure of an investment's volatility compared to the overall market; higher than 1 means more volatile.
Assets under management (AUM): The total market value of assets that a fund manages on behalf of investors.
Max drawdown: The largest percentage drop from a fund's peak value to its lowest point over a period.
S&P 500 Index: A stock market index tracking the 500 largest publicly traded U.S. companies.
Sector diversification: The spread of investments across different industries to reduce risk.
Growth stocks: Companies expected to grow earnings faster than the market average, often reinvesting profits instead of paying dividends.
Total return: The investment's price change plus all dividends and distributions, assuming those payouts are reinvested.
Portfolio concentration: The degree to which a fund's assets are invested in a small number of holdings or sectors.

Katie Brockman has positions in Vanguard S&P 500 ETF. The Motley Fool has positions in and recommends Apple, Microsoft, Nvidia, and Vanguard S&P 500 ETF. The Motley Fool recommends the following options: long January 2026 $395 calls on Microsoft and short January 2026 $405 calls on Microsoft. The Motley Fool has a disclosure policy.