Why Invest in Index Funds?

Advantages of Using Index Funds

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Index funds are mutual funds or exchange-traded funds (ETFs) that invest in such a way that the performance of the fund closely tracks that of the target benchmark index, such as the S&P 500. Because of their passive nature, index funds generally have lower expenses and potentially higher long-term returns than actively-managed funds.

Most investors have heard of index funds and that they are smart choices for building a portfolio of mutual funds. But not everyone knows the real advantages that index funds provide. Let's start with the basics of index investing and then to the advantages of index funds.

What is an Index?

An index, with regard to investing, is a sampling of stocks or bonds that represent a particular segment of the overall financial markets. For example, the Standard & Poor’s 500 (S&P 500), is an index representing roughly 500 of the largest US companies, such as Apple, (AAPL), Amazon (AMZN), Wal-Mart (WMT), Microsoft (MSFT) and Exxon Mobil (XOM).

What Are the Advantages of Index Funds?

There are three primary reasons that investors should consider using index funds for their own investment strategies. The primary advantages of index funds are passive management, low expenses, and broad diversification.

  • Passive Management: Mutual funds can either be actively-managed or passively-managed.The manager of an actively-managed stock mutual fund, for example, is actively buying and selling stocks with the goal of "beating the market," which is measured by a particular benchmark, such as the S&P 500. There is significant risk, however, that the active manager will make poor decisions and under-perform the S&P 500 (more than two-thirds of actively-managed funds do not outperform the indexes for periods longer than 10 years). In contrast, the manager of an index fund, which is passively-managed, is seeking only to buy and hold securities that represent the given index for purposes of matching the performance of the index, not to beat it. In summary, the reason passive management is good for the investor is captured in the saying, "If you can't beat 'em, join 'em."
  • Low Expenses: Keeping costs low are a large advantage for index funds and the cost savings translate to higher returns for the investor. The low costs of index funds are a function of their passive management. When managers are not spending their time and money researching stocks and/or bonds to buy and sell for the portfolio, the costs in managing the fund are much lower than that of actively-managed funds. These costs savings are then passed along to the investor. For this reason, look for the index funds with the lowest expense ratios.
  • Broad Diversification: An investor can capture the returns of a large segment of the market in one index fund. Index funds often invest in hundreds or even thousands of holdings; whereas actively-managed funds sometimes invest in less than 50 holdings. Generally, funds with higher amounts of holdings have lower relative market risk than those with fewer holdings; and index funds typically offer exposure to more securities than their actively-managed counterparts.

The most reputable mutual fund companies with a good variety of low-cost index funds include Vanguard and Fidelity. You can also buy index funds through an online discount broker, such as Charles Schwab or TD Ameritrade.

Disclaimer: The information on this site is provided for discussion purposes only, and should not be misconstrued as investment advice. Under no circumstances does this information represent a recommendation to buy or sell securities.