What Is an Index Fund ?

A mutual fund or exchange-traded fund (ETF) that tracks or matches the components of a financial market index, such as the Standard & Poor’s 500 Index, is known as an index fund (S&P 500). A broad market exposure, minimal operating expenses, and low portfolio turnover are all claimed benefits of an index mutual fund. Regardless of market conditions, these funds track their benchmark index.

Index funds are commonly regarded as appropriate core portfolio holdings for retirement accounts such as IRAs and 401(k)s. Warren Buffett, the legendary investor, has advocated index funds as a safe harbour for retirement money. Rather of choosing specific businesses to invest in, he believes it is more cost effective for the ordinary investor to acquire all of the S&P 500 firms through an index fund.

Also Read: What are equity Mutual Funds?

An Index Fund’s Operation

The term “indexing” refers to a type of passive fund management. Instead of actively stock selecting and market timing—that is, deciding which securities to invest in and when to purchase and sell them—a fund portfolio manager develops a portfolio whose holdings mimic those of a certain index. The theory is that by replicating the index’s profile—the stock market as a whole or a big section of it—the fund will be able to equal its performance.

For practically every financial market that exists, there is an index and an index fund. The most popular index funds in the United States follow the S&P 500 index. However, there are a variety of alternative indices that are extensively used, such as:

MSCI EAFE Index, which includes international companies from Europe, Australasia, and the Far East2 Wilshire 5000 Total Market Index, the largest U.S. equities index1

Bloomberg U.S. Aggregate Bond Index, which tracks the whole bond market3 Nasdaq Composite Index, which comprises 3,000 Nasdaq-listed stocks4 Dow Jones Industrial Average (DJIA), which comprises 30 large-cap businesses.

For example, an index fund tracking the DJIA would invest in the same 30 major, publicly traded firms that make up the index.

Index funds’ portfolios only change significantly when their benchmark indices change. If the fund follows a weighted index, the managers may adjust the percentage of different securities to reflect the weight of their participation in the benchmark on a quarterly basis. Weighting is a mechanism for balancing the impact of each individual position in an index or portfolio.

Actively Managed Funds vs. Index Funds

Investing in an index fund is a passive investment strategy. Active investment, as practised in actively managed mutual funds (the ones with the securities-picking, market-timing portfolios mentioned above), is the polar opposite of passive investing.


The reduced management expense ratio of index funds is one of their key advantages over actively managed alternatives. All operational expenditures, including as payments to advisers and managers, transaction fees, taxes, and accounting fees, are included in a fund’s expense ratio, also known as the management expense ratio. 

Index fund managers do not require the assistance of research analysts or anyone who aid in the company selection process because they are merely repeating the performance of a benchmark index. Index fund managers trade their assets less frequently, which means they pay less in transaction fees and charges. Actively managed funds, on the other hand, have larger staffs and execute more transactions, raising the cost of doing business.

The fund’s expense ratio reflects the additional expenses of fund management, which are passed on to investors. As a result, low-cost index funds often cost less than 1%—0.2% to 0.50% is normal, with some firms providing even lower expense ratios of 0.05% or less—in comparison to the significantly higher fees charged by actively managed funds, which typically range from 1% to 2.50%.

Expense ratios have a direct influence on a fund’s overall performance. Actively managed funds are immediately at a disadvantage versus index funds due to their frequently higher cost ratios, and thus struggle to stay up with their benchmarks in terms of overall return.

Check the mutual fund or ETF screener in your online brokerage account to determine which index funds are accessible to you.


  • Diversification reduces risk.
  • Low expenditure to revenue ratios
  • Long-term profitability.
  • It’s ideal for buy-and-hold investors.
  • Investors benefit from lower taxes.


  • Market swings and crashes make you vulnerable.
  • Flexibility is lacking.
  • There is no human aspect.
  • Gains are limited.

Better Profits?

Passive funds, according to proponents, have outperformed most actively managed mutual funds. In fact, the vast majority of mutual funds do not outperform their benchmark or broad market indices. According to SPIVA Scorecard data from S&P Dow Jones Indices, about 75% of large-cap U.S. funds achieved a return that was less than the S&P 500 for the five-year period ending Dec. 31, 2020.

Passively managed funds, on the other hand, don’t try to outperform the market. Instead, their method is to equal the market’s overall risk and return, assuming that the market always wins.

Over time, passive management tends to result in favourable results. Active mutual funds fare better over shorter time periods. Only approximately 60% of large-cap mutual funds underperformed the S&P 500 over the course of a year, according to the SPIVA Scorecard. To put it another way, around two-fifths of them defeat it in the near run. Actively managed money rules in other areas as well. Over 86% of mid-cap mutual funds, for example, outperformed the S&P MidCap 400 Growth Index over the course of a year.

Also Read: What are Debt Funds, exactly?

Index Funds in the Real World

Since the 1970s, index funds have been around. In the 2010s, the popularity of passive investing, the allure of cheap fees, and a long-running bull market all conspired to drive them skyrocketing. Investors put more than $400 billion into index funds across all asset classes in 2021, according to Morningstar Research. Actively managed funds saw $188 billion in withdrawals during the same time period.

The fund that started it all, launched by Vanguard chairman John Bogle in 1976, is still one of the finest in terms of long-term performance and low cost. In terms of composition and performance, the Vanguard 500 Index Fund has closely followed the S&P 500. Vanguard’s Admiral Shares had an average annual return of 7.84 percent as of June 2021, compared to 7.86 percent for the S&P 500. The expenditure ratio is 0.04 percent, with a $3,000 minimum commitment.

What are index exchange-traded funds (index ETFs) and how do they work?

ETFs are a type of index fund that can be organised in a variety of ways (ETFs). These are basically stock portfolios managed by a professional financial firm, with each share representing a modest ownership position in the overall portfolio. The objective of an index fund is not to beat the underlying index, but rather to mimic its performance. If a certain stock makes up 1% of the index, for example, the index fund manager will try to replicate that composition by having that stock make up 1% of its portfolio.

Are there any expenses associated with index funds?

Index funds do charge fees, although they are often substantially cheaper than those charged by comparable products. Many index funds charge less than 0.20 percent in fees, but active funds frequently charge more than 1.00 percent in costs. When accumulated over longer time periods, this difference in costs can have a significant impact on investors’ results. One of the key reasons why index funds have grown so popular in recent years is because of this.

Frequently Asked Questions about Index Fund

Is it good to invest in index funds?

Index funds have consistently outperformed other forms of mutual funds over time. Low costs, tax advantages (they create less taxable income), and low risk (due to their wide diversification) are all advantages of index funds.

What is an example of an index fund?

A mutual fund or exchange-traded fund that attempts to match the returns of a market index is known as a “index fund.” Index funds may strive to track market indexes such as the S&P 500 Index, the Russell 2000 Index, and the Wilshire 5000 Total Market Index, to name a few.

Do index funds pay dividends?

In most circumstances, they are required to do so by law. As a result, index funds distribute any interest or dividends produced by the fund’s individual investments. After subtracting the fund’s costs.

Can you lose money investing in index funds?

An index fund, like any other investment, has the potential to lose money. However, if you invest in an index fund and keep it for the long term, your investment is far more likely to grow in value. You may then be able to benefit from your investment.

Do I have to pay taxes on index funds?

For a handful of reasons, index funds—whether mutual funds or exchange-traded funds—are naturally tax-efficient: Index funds do not move in and out of assets as often as active funds do since they merely mimic the holdings of an index.

Which is better equity fund or index fund?

In an index fund, you just have to worry about market risk or systematic risk, however in an equity fund, you also have to worry about unsystematic risk variables affecting your fund returns. Active investing, on the other hand, assumes that stock selection will result in better returns.