Differences between ETFs, mutual funds and index funds

Learning to invest is one of the most powerful financial moves you can make. For most people, that journey starts with investment funds. ETFs, mutual funds and index funds are 3 of the most common options out there—and they’re some of the easiest investments to get started with.

Understanding how ETFs, mutual funds and index funds differ is a great place to begin. This guide walks you through what each one is, how they work and what sets them apart so you can start investing with clarity and confidence.

Understanding the basics of investing

Before diving into each option, it helps to clear up a common point of confusion in beginner investing. ETFs and mutual funds are both pooled investment vehicles, but they differ in how they’re structured, priced and traded. An index fund, on the other hand, refers to an investment strategy.

Index funds are designed to track the performance of a specific market index, such as the S&P 500. An index fund can be structured as either a mutual fund or an ETF. Understanding this distinction—structure vs. strategy—can make it easier to see how these investments fit together.

What is a mutual fund?

A mutual fund is one of the most straightforward ways to start building an investment portfolio. Instead of buying individual stocks or bonds on your own, you pool your money with other investors, and a fund manager takes it from there.

How mutual funds work

When you invest in a mutual fund, your money gets combined with contributions from thousands of other investors. That combined pool is used to buy a diversified mix of assets—stocks, bonds or both—depending on the fund’s focus. Because you’re sharing the investment with so many others, you get broad exposure without needing a large sum of money to get started.

One thing that sets mutual funds apart from ETFs is how they’re priced and traded. Mutual funds are bought and sold once per day, after the market closes, at a price based on the fund’s net asset value (NAV). NAV is calculated as the total value of the fund’s assets minus its liabilities, divided by the number of shares outstanding. Depending on the fund and share class, investors may also pay sales charges or other fees.

Active vs. passive mutual funds

Mutual funds can be either actively or passively managed. An actively managed fund usually has a team led by a portfolio manager making decisions about what to buy and sell. A passively managed fund (like an index mutual fund) simply tracks a market index.

What to know about costs and minimums

Mutual funds may include sales charges (loads), depending on the fund and share class. These can be applied when you buy (front-end load) or sell (back-end load) shares. In addition, mutual funds carry an expense ratio. This is an annual fee expressed as a percentage of your investment that covers the fund’s operating costs. Actively managed funds tend to have higher expense ratios than passive ones.

Some mutual funds require a minimum initial investment, while others allow you to get started with as little as $0 to $250. Minimums vary by fund and provider.

Who mutual funds work well for

Mutual funds are a natural fit for investors who prefer to invest on a set schedule, contributing the same amount regularly, regardless of market conditions. It’s why many employer-sponsored retirement plans offer mutual funds as the primary investment option. If you’ve ever contributed to a 401(k), there’s a good chance you’ve already invested in one.

What is an exchange-traded fund (ETF)?

An ETF is a lot like a mutual fund in one important way: it pools money from many investors to buy a diversified mix of assets. However, what makes ETFs different is how they’re bought and sold. That difference has some practical implications worth understanding.

How ETFs work

When you buy an ETF, you’re buying shares of a fund that trades on a stock exchange, like individual company stocks. That means ETF prices move throughout the trading day based on supply and demand, rather than being set once at market close like a mutual fund. You can buy or sell an ETF any time the market is open.

Many ETFs are passively managed and track a market index, though actively managed ETFs have become more widely available in recent years. Passive ETFs often have lower expense ratios than actively managed funds, though costs vary depending on the fund’s strategy and management style.

Types of ETFs

ETFs come in a variety of flavors depending on what they invest in:

• Index ETFs track a specific index or a broad market index (the S&P 500 or the Nasdaq)
• Sector ETFs focus on a specific industry, like technology or healthcare
• Bond ETFs hold fixed-income investments rather than stocks

Most beginner investors start with index ETFs, which offer broad market exposure at a low cost.

What to know about costs and minimums

One of the biggest practical differences between ETFs and mutual funds is the minimum investment. With most ETFs, you can get started by buying as little as one share. ETFs may carry trading commissions depending on your brokerage, though many major platforms have eliminated them.

Who ETFs work well for

ETFs are a great option for investors who want flexibility and low costs. Because there’s no minimum investment requirement beyond the price of a single share, they’re accessible to investors at just about any budget. They’re also a popular choice for investors who want to build a diversified portfolio gradually over time.

ETFs vs. mutual funds: How they compare

If you’re looking for an introduction to investing, mutual funds and ETFs are both beginner-friendly options. Here are the key differences in how they stack up across the factors that matter most to new investors.

Table showing example of asset allocations

	Exchange-traded funds	Mutual funds
Trading	Throughout the day	Once per day, after market close
Management style	Mostly passive	Active or passive
Expense ratios	Generally low	Low (passive) to higher (active)
Minimum investment	Price of 1 share	Price of 1 share $0 to $250+ (varies by fund and provider)
Good for	Flexible, low-cost investing	Hands-off, scheduled investing

What is an index fund?

After looking at the differences between mutual funds and ETFs, index funds become easier to understand. An index fund, whether it’s structured as an ETF or a mutual fund, tracks a market index.

What is a market index?

A market index is a collection of securities (stocks, bonds or both) that represents a particular segment of the market. The S&P 500, for example, tracks 500 of the largest publicly traded companies in the United States. The Nasdaq Composite tracks thousands of companies listed on the Nasdaq exchange, with a heavy concentration in technology. 

When a fund tracks an index, it holds the same securities in roughly the same proportions. When the index goes up, the fund goes up with it.

How index funds are managed

Because index funds mirror an existing index, they don’t need a team of professionals making active investment decisions. In fact, most actively managed funds don’t outperform their benchmark index over the long term. 

That passive approach also helps keep costs down. Index funds tend to have some of the lowest expense ratios available. It also means index fund performance closely follows the market rather than trying to beat it, which is actually a feature for many investors. 

Who index funds work well for

Index funds are widely considered one of the best starting points for new investors. They offer instant diversification, low costs and a straightforward buy-and-hold approach that doesn’t require constant monitoring. Whether you choose an index ETF or an index mutual fund, you’re getting the same core benefit: broad market exposure without the complexity of picking individual investments.

Which one is right for you?

Understanding the differences between ETFs, mutual funds and index funds is one thing. Knowing how to apply it to your own situation is another. The best choice depends on a few personal factors:

• How much money are you starting with? If you’re working with a smaller amount, an ETF may be more accessible—just the price of a share.
• Do you want to automate your investments? Mutual funds tend to make that easier because many allow you to set up automatic contributions on a schedule.
• Are you investing through a retirement account or a taxable account? If taxes are a consideration, ETFs are generally the more tax-efficient option.

Some common starting points

Different situations call for different investment approaches. Here are a few examples to illustrate how investors commonly think about these options:

• If you’re just starting out with a small, regular contribution—$50 or $100 a month—an index mutual fund can be a simple, low-cost way to begin. Many allow automatic contributions with no trading commissions.
• If you have a lump sum to invest and want to keep costs low, index ETFs are worth a closer look. They offer broad market exposure, low expense ratios and no minimum investment beyond the share price.
• If you’d prefer to have professionals actively managing your investments, an actively managed mutual fund may be a better fit. That said, it’s worth comparing expense ratios before committing.

You don’t have to choose just one option

Many investors hold a mix of ETFs and mutual funds. If you contribute to a 401(k), for example, you’re likely already invested in mutual funds. An IRA or a taxable brokerage account might hold ETFs alongside those. They can work together as part of a balanced, diversified strategy. 

Building wealth starts with knowing your options

ETFs, mutual funds and index funds aren’t competing options; they’re tools. And, like any tools, their value depends on how you use them.  

Ready to put those tools to work? Navy Federal Investment Services’s Digital Investor makes it easy to start building a diversified portfolio on your own terms.^{Footnote [1]}