Investing in a total U.S. stock market fund is increasingly considered a wise choice for long-term portfolio strategies. Total market funds offer an effective means to diversify investments, encompassing the broad spectrum of the market under a single ticker symbol. Particularly compelling are two of the largest Exchange-Traded Funds (ETFs): the Vanguard Total Stock Market ETF and the iShares Core S&P Total U.S. Stock Market ETF. While both funds aim to provide a comprehensive representation of the U.S. stock market, an in-depth comparison reveals some nuanced distinctions.
The Vanguard Total Stock Market ETF tracks the CRSP US Total Market Index, which represents nearly the entirety of the investable U.S. stock market, including a wide range of large-, mid-, and small-cap stocks. In contrast, the iShares Core S&P Total U.S. Stock Market ETF follows the S&P Total Market Index, integrating the S&P 500 with the S&P Completion Index. Thus, both ETFs serve a similar purpose of capturing the complete U.S. stock market, albeit through different methodologies.
A significant difference lies in the number of individual holdings within each fund. The Vanguard ETF encompasses approximately 3,500 stocks, while the iShares version includes around 2,500. Although this disparity may initially seem substantial, its practical implications are less pronounced. Most of the additional stocks captured by Vanguard comprise micro-cap stocks, which the iShares fund excludes for reasons related to liquidity and company size. In a market-cap-weighted strategy, these smaller stocks typically constitute only about 1% to 2% of the total portfolio.
The core of both ETFs shares considerable overlap, resulting in almost identical performance records over time. Their historical track records suggest that investors can expect similar returns regardless of their chosen fund. Both ETFs charge an expense ratio of 0.03%, ensuring they remain affordable options. Additionally, they boast high liquidity, facilitating easy trading without incurring significant costs.
Considering the narrow scope for differentiation, the decision on which ETF to choose becomes a matter of personal preference. The primary divergence is that the Vanguard ETF includes those extra 1,000 micro-cap stocks. Given their minimal impact on overall portfolio performance, it could be argued that the Vanguard Total Stock Market ETF may provide a more comprehensive exposure to the total U.S. stock market.
In conclusion, while the Vanguard ETF appears to have a marginal edge due to its broader selection of stocks, investors can confidently invest in either fund. The likelihood of experiencing significant differences in performance or costs between the two is notably slim. Ultimately, both options represent solid choices for anyone looking to solidify their long-term investment strategy in the U.S. stock market.

