The Hidden Concentration Risk in VOO

The Hidden Concentration Risk in VOO

What You Actually Own When You Buy the S&P 500

“I can’t tell you how to invest your money, but I can let you know how I’m investing mine.”

Why did the Trail Boss start with VOO—and what should investors understand before assuming that owning an S&P 500 index fund means they are fully diversified?

In this episode of Trail Boss Radio, we take a closer look at the Vanguard S&P 500 ETF (VOO), its role in the Unbridled Nation investing journey, and the hidden concentration risk that can come with market-cap-weighted index funds.

VOO provides exposure to hundreds of major U.S. companies through one exchange-traded fund. Its low expense ratio is one of its attractive features. But there’s another side to the story: the largest companies make up a disproportionately large share of the fund.

According to the Vanguard fact-sheet figures cited in our notebook, VOO’s expense ratio is 0.03%, and its top 10 holdings account for more than 35% of the fund. That means a relatively small group of mega-cap companies can have an outsized influence on performance.

Fund holdings and weightings change over time. Check Vanguard’s latest fact sheet for current figures.

What We Explore in This Episode

What is VOO? A plain-English look at an ETF designed to track the S&P 500 Index.

What do you actually own? Understanding how market-cap weighting gives larger companies more influence.

The concentration question: Why owning hundreds of stocks does not mean every company carries equal weight.