The Vanguard S&P 500 ETF (VOO) has taken a commanding lead over its main rival, the SPDR S&P 500 ETF Trust (SPY), becoming the world’s largest ETF. VOO now manages $648 billion in assets, giving it a $44 billion advantage over SPY. Investors have poured $59.5 billion into VOO since the beginning of the year, while withdrawing $24 billion from SPY, resulting in an $83.5 billion difference in flows.
VOO’s low expense ratio of 0.03% is a significant factor in its popularity compared to SPY’s 0.09% fee. However, cost is not the only reason for VOO’s success. The iShares Core S&P 500 ETF (IVV), which has the same 0.03% expense ratio as VOO, has only attracted $1.3 billion in inflows year to date, despite being the third-largest ETF globally with $587 billion in assets.
Vanguard’s dominance solidifies in ETF market
Vanguard’s strong brand reputation and investor loyalty have played a crucial role in VOO’s dominance. Even when other funds offer the same exposure at an identical price, investors continue to favor Vanguard.
VOO is on pace to surpass its record inflow of $116 billion from last year, having already secured nearly half that amount in 2025. The fund’s position as the leader in the S&P 500 ETF category and the broader ETF market appears stronger than ever. As VOO continues to attract significant inflows and widen its lead over SPY, it solidifies its status as the world’s largest and most popular ETF.
Investors’ preference for Vanguard’s low-cost, investor-friendly approach has been a key driver in this ongoing shift within the ETF landscape.