The race to become the first $1 trillion exchange-traded fund (ETF) is heating up, and Vanguard's VOO is poised to cross that historic threshold. Meanwhile, investors in State Street's SPY are paying significantly higher fees for exposure to the exact same S&P 500 index. This divergence highlights a growing trend among cost-conscious investors who are shifting their assets to cheaper alternatives.

VOO's Meteoric Rise to $1 Trillion

VOO, the Vanguard S&P 500 ETF, has been on a remarkable trajectory, with assets under management now approaching the $1 trillion mark. If achieved, VOO would become the first ETF in history to reach this milestone, cementing its position as a dominant force in the investment landscape. The fund's low expense ratio of just 0.03% has been a major draw for both retail and institutional investors, fueling consistent inflows over the past several years.

Industry analysts attribute VOO's rapid growth to a combination of factors, including the broader shift toward passive investing, the appeal of Vanguard's low-cost model, and the performance of the S&P 500 itself. As of August 2026, VOO's assets stand at approximately $980 billion, according to the latest data, and it could hit the trillion-dollar mark within the next few weeks if market conditions remain favorable.

Why VOO Is Outpacing SPY

One of the key reasons VOO is outpacing SPY is its fee structure. SPY, which was launched in 1993 as the first U.S. ETF, charges an expense ratio of 0.0945%—more than three times VOO's fee. On a $10,000 investment, that difference amounts to about $6.45 per year, but on a $1 trillion asset base, the gap becomes staggering. Over time, even small fee differences can erode returns, and investors have taken notice.

Additionally, VOO benefits from Vanguard's unique share class structure, which allows the ETF to share expenses with the mutual fund, further reducing costs. SPY, on the other hand, is a standalone ETF with no such arrangement, making it inherently more expensive to operate.

The Fee Gap: A Closer Look

To understand the magnitude of the fee disparity, consider this: SPY investors pay roughly three times more in annual fees for the same index exposure. With $1 trillion in assets, that translates to an additional $645 million in annual fees for SPY holders compared to VOO holders. This has prompted many financial advisors to recommend VOO over SPY, especially for long-term investors who want to minimize costs.

The fee difference is not just a minor annoyance; it can have a significant impact on long-term returns. For example, a $100,000 investment in SPY over 30 years, assuming a 7% annual return, would cost an investor approximately $33,000 in fees, while the same investment in VOO would cost only $12,000. That's a $21,000 difference—money that could have grown to over $70,000 if reinvested.

Institutional Adoption and ETF Evolution

The shift from SPY to VOO is also evident in institutional flows. Many pension funds, endowments, and asset managers have been reallocating their S&P 500 exposure to VOO to cut costs, further accelerating VOO's growth. Meanwhile, SPY remains the most heavily traded ETF by volume, but its asset growth has been slower, as new money increasingly flows into cheaper alternatives.

This trend underscores a broader evolution in the ETF industry: investors are becoming more fee-sensitive, and product providers are responding with lower-cost options. The success of VOO has prompted other issuers to slash fees on their own S&P 500 ETFs, benefiting all investors.

Key Takeaways

  • VOO is on track to become the first $1 trillion ETF, driven by its ultra-low expense ratio of 0.03%.
  • SPY holders pay more than three times the fee for the same S&P 500 index exposure.
  • Fee differences compound over time, potentially costing SPY investors tens of thousands of dollars in foregone returns.
  • Institutional and retail investors are shifting to VOO, accelerating its asset growth.
  • The ETF industry is evolving toward lower fees, benefiting all investors.

Conclusion

As VOO approaches the $1 trillion milestone, it serves as a powerful reminder of the impact of fees on investor outcomes. While SPY remains a liquid and widely traded fund, its higher cost structure is a growing deterrent for cost-conscious investors. The shift toward VOO is not just a trend; it's a rational response to a simple economic reality: why pay more for the same thing? With VOO on the verge of making history, the message is clear—low costs win.