The performance of the mutual fund depends on the underlying assets that it holds. If these assets increase in value on net, so does the value of the fund's shares. Conversely, if the assets decrease in value, so does the value of the shares.

The fund manager oversees the portfolio, making decisions about how to allocate money across sectors, industries, companies, etc. based on the stated strategy of the fund. By pooling money into a large fund, investors can participate in a professionally managed, diversified group of securities that they wouldn't usually have access to as individuals. This diversification and access are a key benefit of mutual funds for individual investors.

Investors typically earn a return from a mutual fund in three ways:

1. Income is earned from dividends on stocks and interest on bonds held in the fund's portfolio, and it pays out nearly all of the income it receives over the year to fund owners in the form of a distribution. Funds often give investors a choice either to receive a check for distributions or to reinvest the earnings to purchase additional shares of the mutual fund.
2. Portfolio Distributions: If the fund sells securities that have increased in price, the fund realizes a capital gain, which most funds also pass on to investors in a distribution.
3. Capital Gains: When the fund's shares increase in price, you can sell your mutual fund shares for a profit in the market.

When researching the returns of a mutual fund, an investor will typically see "total return," or the net change in value, either up or down, of an investment over a specific period. This includes any interest, dividends, or capital gains the fund generated as well as the change in its market value over some time. In most cases, total returns are calculated for one, five, and 10-year periods as well as since the day the fund opened, or the inception date.

There are several types of mutual funds available for investment, though most mutual funds fall into one of four main categories which include stock funds, money market funds, bond funds, and target-date funds.

As the name implies, this fund invests principally in equity or stocks. Within this group are various subcategories. Some equity funds are named for the size of the companies they invest in: small-, mid-, or large-cap. Others are named by their investment approach: aggressive growth, income-oriented, value, and others. Equity funds are also categorized by whether they invest in domestic (U.S.) stocks or foreign equities. To understand the universe of equity funds, use a style box, an example of which is below.

Small-cap companies have a market capitalisation of less than ₹5,000 crores. These companies are relatively smaller in size and have a significant growth potential. What makes them risky is the low probability that they will be successful over time. This makes the stocks of such companies volatile in nature. Small-cap companies have a long history of underperformance but when an economy emerges from a recession, small-cap stocks often prove to be outperformers.

A mutual fund that generates a minimum return is part of the fixed income category. A fixed-income mutual fund focuses on investments that pay a set rate of return, such as government bonds, corporate bonds, or other debt instruments. The fund portfolio generates interest income that is passed on to the shareholders.

Sometimes referred to as bond funds, these funds are often actively managed and seek to buy relatively undervalued bonds to sell them at a profit. These mutual funds will likely pay higher returns but aren't without risk. For example, a fund specializing in high-yield junk bonds is much riskier than a fund that invests in government securities.8

Because there are many different types of bonds, bond funds can vary dramatically depending on where they invest, and all bond funds are subject to interest rate risk.

Index funds invest in stocks that correspond with a major market index such as the S&P 500 or the Dow Jones Industrial Average (DJIA). This strategy requires less research from analysts and advisors, so fewer expenses are passed on to shareholders, and these funds are often designed with cost-sensitive investors in mind.

Balanced funds invest in a hybrid of asset classes, whether stocks, bonds, money market instruments, or alternative investments. The objective of this fund, known as an asset allocation fund, is to reduce the risk of exposure across asset classes.

Some funds are defined with a specific allocation strategy that is fixed, so the investor can have a predictable exposure to various asset classes. Other funds follow a strategy for dynamic allocation percentages to meet various investor objectives. This may include responding to market conditions, business cycle changes, or the changing phases of the investor's own life.

The portfolio manager is commonly given the freedom to switch the ratio of asset classes as needed to maintain the integrity of the fund's stated strategy.

The money market consists of safe, risk-free, short-term debt instruments, mostly government Treasury bills. An investor will not earn substantial returns, but the principal is guaranteed. A typical return is a little more than the amount earned in a regular checking or savings account and a little less than the average certificate of deposit (CD).9

Income funds are named for their purpose: to provide current income on a steady basis. These funds invest primarily in government and high-quality corporate debt, holding these bonds until maturity to provide interest streams. While fund holdings may appreciate, the primary objective of these funds is to provide steady cash flow​ to investors. As such, the audience for these funds consists of conservative investors and retirees.

An international fund, or foreign fund, invests only in assets located outside an investor's home country. Global funds, however, can invest anywhere around the world. Their volatility often depends on the unique country's economy and political risks. However, these funds can be part of a well-balanced portfolio by increasing diversification, since the returns in foreign countries may be uncorrelated with returns at home.

Sector funds are targeted strategy funds aimed at specific sectors of the economy, such as financial, technology, or health care. Sector funds can be extremely volatile since the stocks in a given sector tend to be highly correlated with each other.

Regional funds make it easier to focus on a specific geographic area of the world. This can mean focusing on a broader region or an individual country.

Socially responsible funds, or ethical funds, invest only in companies that meet the criteria of certain guidelines or beliefs. For example, some socially responsible funds do not invest in "sin" industries such as tobacco, alcoholic beverages, weapons, or nuclear power. Other funds invest primarily in green technology, such as solar and wind power or recycling.10

A mutual fund has annual operating fees or shareholder fees. Annual fund operating fees are an annual percentage of the funds under management, usually under 1%, known as the expense ratio. A fund's expense ratio is the summation of the advisory or management fee and its administrative costs.11

Shareholder fees are sales charges, commissions, and redemption fees paid directly by investors when purchasing or selling the funds. Sales charges or commissions are "the load" of a mutual fund. When a mutual fund has a front-end load, fees are assessed when shares are purchased. For a back-end load, mutual fund fees are assessed when investors sell their shares.

Sometimes, however, an investment company offers a no-load mutual fund, which doesn't carry any commission or sales charge. These funds are distributed directly by an investment company, rather than through a secondary party. Some funds also charge fees and penalties for early withdrawals or selling the holding before a specific time has elapsed.12

Traditionally, individual investors purchase mutual funds with A-shares through a broker. This purchase includes a front-end load of up to 5% or more, plus management fees and ongoing fees for distributions, also known as 12b-1 fees. Financial advisors selling these products may encourage clients to buy higher-load offerings to generate commissions. With front-end funds, the investor pays these expenses as they buy into the fund.

To remedy these problems and meet fiduciary-rule standards, investment companies have designated new share classes, including "level load" C shares, which generally don't have a front-end load but carry a 12b-1 annual distribution fee of up to 1%.

Funds that charge management and other fees when an investor sells their holdings are classified as Class B shares.14

Investing in mutual funds is a fairly straightforward process that involves the following steps:

1. Make sure you have a brokerage account with enough cash on hand, and with access to mutual fund shares.
2. Identify specific mutual funds that match your investing goals in terms of risk, returns, fees, and minimum investments. Many platforms offer fund screening and research tools.
3. Determine how much you want to invest initially and submit your trade. If you choose, you can often set up automatic recurring investments as desired.
4. Monitor and review performances periodically, making adjustments as needed.
5. When it is time to close your position, enter a sell order on your platform.

The value of the mutual fund depends on the performance of the securities it invests in. When buying a unit or share of a mutual fund, an investor buys the performance of its portfolio or, more precisely, a part of its value. Investing in a share of a mutual fund differs from investing in stock shares. Unlike stock, mutual fund shares do not give their holders voting rights. A mutual fund share represents investments in many different stocks or other securities.

The price of a mutual fund share is referred to as the net asset value (NAV) per share, sometimes expressed as NAVPS. A fund's NAV is derived by dividing the total value of the securities in the portfolio by the total amount of shares outstanding. Outstanding shares are those held by all shareholders, institutional investors, and company officers or insiders.

Mutual fund shares can typically be purchased or redeemed at the fund's current NAV, which doesn't fluctuate during market hours but is settled at the end of each trading day. The price of a mutual fund is also updated when the NAVPS is settled.16

The average mutual fund holds different securities, which means mutual fund shareholders gain diversification. Consider an investor who buys only Google stock and relies on the success of the company's earnings. Because all of their dollars are tied to one company, gains and losses depend on its success. However, a mutual fund may hold Google in its portfolio where gains and losses of other companies within the fund offset the gains and losses of just one stock.

There are a variety of reasons that mutual funds have been the retail investor's vehicle of choice, with an overwhelming majority of money in employer-sponsored retirement plans invested in mutual funds.

Investors have the freedom to research and select from managers with a variety of styles and management goals. A fund manager may focus on value investing, growth investing, developed markets, emerging markets, income, or macroeconomic investing, among many other styles. This variety allows investors to gain exposure to not only stocks and bonds but also commodities, foreign assets, and real estate through specialized mutual funds. Mutual funds provide opportunities for foreign and domestic investment that may not otherwise be directly accessible to ordinary investors.

Mutual funds are subject to industry regulation that ensures accountability and fairness to investors.

Liquidity, diversification, and professional management all make mutual funds attractive options; however, mutual funds have drawbacks too.

Like many other investments without a guaranteed return, there is always the possibility that the value of your mutual fund will depreciate. Equity mutual funds experience price fluctuations, along with the stocks in the fund's portfolio. The Federal Deposit Insurance Corporation (FDIC) does not guarantee mutual fund investments.17

Mutual funds require a significant amount of their portfolios to be held in cash to satisfy share redemptions each day. To maintain liquidity and the capacity to accommodate withdrawals, funds typically have to keep a larger portion of their portfolio as cash than a typical investor might. Because cash earns no return, it is often referred to as a "cash drag."

Mutual funds provide investors with professional management, but fees that reduce the fund's overall payout are assessed to mutual fund investors regardless of the performance of the fund. Since fees vary widely from fund to fund, failing to pay attention to the fees can have negative long-term consequences as actively managed funds incur transaction costs that accumulate over each year.

"Diworsification"—a play on words—is an investment or portfolio strategy that implies too much complexity can lead to worse results. Many mutual fund investors tend to overcomplicate matters. That is, they acquire too many funds that are highly related and, as a result, lose the benefits of diversification.

Dilution is also the result of a successful fund growing too big. When new money pours into funds that have had strong track records, the manager often has trouble finding suitable investments for all the new capital to be put to good use.

The Securities and Exchange Commission (SEC) requires that funds have at least 80% of assets in the particular type of investment implied in their names.18How the remaining assets are invested is up to the fund manager. However, the different categories that qualify for 80% of the assets may be vague and wide-ranging. A fund can, therefore, manipulate prospective investors via its title. For example, a fund that focuses narrowly on Argentinian stocks could be sold with a far-ranging title like "International High-Tech Fund."

A mutual fund allows you to request that your shares be converted into cash at any time, however, unlike stock that trades throughout the day, many mutual fund redemptions​ take place only at the end of each trading day.19

When a fund manager sells a security, a capital-gains tax is triggered. Taxes can be mitigated by investing in tax-sensitive funds or by holding non-tax-sensitive mutual funds in a tax-deferred account, such as a 401(k) or IRA.20

Researching and comparing funds can be difficult. Unlike stocks, mutual funds do not offer investors the opportunity to juxtapose the price to earnings (P/E) ratio, sales growth, earnings per share (EPS), or other important data. A mutual fund's net asset value can offer some basis for comparison, but given the diversity of portfolios, comparing the proverbial apples to apples can be difficult, even among funds with similar names or stated objectives. Only index funds tracking the same markets tend to be genuinely comparable.

One of the most notable mutual funds is Fidelity Investments' Magellan Fund (FMAGX). Established in 1963, the fund had an investment objective of capital appreciation via investment in common stocks. The fund's height of success was between 1977 and 1990 when Peter Lynch served as its portfolio manager. Under Lynch's tenure, Magellan's assets under management increased from $18 million to $14 billion.21

Fidelity's performance continued strong, and assets under management (AUM) grew to nearly $110 billion in 2000. By 1997, the fund had become so large that Fidelity closed it to new investors and would not reopen it until 2008.22

As of February 2023, Fidelity Magellan has approximately $30 billion in assets and has been managed by Sammy Simnegar since February 2019. The S&P 500 is the fund's primary benchmark.23

Index funds are a type of mutual fund that aims to replicate the performance of a market benchmark, or index. For example, an S&P 500 index fund tracks that index by holding the 500 companies in the same proportions. A key goal of index funds is minimizing costs to closely mirror their index.

By contrast, actively managed mutual funds try to beat the market by stock picking and shifting allocations. The fund manager makes choices to achieve returns greater than a benchmark through their investing strategy and research.

Index funds offer market returns at lower costs, while active mutual funds aim for higher returns through skilled management that often comes at a higher price. Investors should consider costs, time horizons, and risk appetite when deciding between index or managed mutual fund investing.