How to Invest in Index Funds

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Index funds are a type of investment that mirrors a market index, aiming to replicate the performance of the underlying index by investing in the same basket of assets. When you buy shares of an index fund, you own a portion of the fund's total holdings.

Like other types of investments, index funds can have different benefits and risks. One benefit of index funds is their built-in diversification. They're also known for being lower-cost and tax-efficient when compared with actively managed funds. Here are seven steps you can take to invest in index funds.

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1. Understand Index Funds

Market indexes measure the performance of a market or a sector of a market. Index funds aim to copy the performance of a specific market index by investing in the same assets. Index funds typically invest passively, mirroring an index, and as such are typically less expensive than actively managed funds.

The most popular and widely cited market index is the S&P 500, which tracks the market performance of 500 of the largest publicly traded companies in the United States. But there are many different indexes on which an index fund may be based (more on this below).

Learn more >> What Are Index Funds?

2. Know Your Goals

Getting a clear picture of your goals and investment time horizon is key for picking index funds that align with your needs. Index funds can be composed of stocks, bonds and other securities, which makes them an efficient way to achieve the right asset allocation for your goals.

There are index funds that invest primarily in stocks, which offer the potential for more growth at the cost of more risk. You may be able to afford more exposure to risk if you're investing for a far-off goal.

On the other hand, if you're investing for a near-term goal, a more conservative asset allocation is a safer play. You could choose a fund that invests in fixed income assets to ensure you're preserving wealth (more on this below).

3. Research Specific Index Funds

Once you know your goals, you're ready to dig into researching specific index funds. Here are some types of index funds to consider.

Broad Market Index Funds

Broad market funds are a diverse option that invest widely in stocks, bonds and other asset classes with the intent to match the growth of a broad market index.

For example, a broad market index fund might track the S&P 500, the Dow Jones Industrial Average (composed of 30 highly rated and robust company stocks) or the Nasdaq Composite Index (a large index made up of the stocks sold on the Nasdaq Market Exchange, known for heavy tech representation).

Learn more >> What Is a Stock Market Index?

You can also buy broad-based funds designed for ESG investing. And there are international index funds that track the performance of foreign stock markets (note that these come with their own set of risks and tax implications).

Fixed-Income Index Funds

Also called bond funds, fixed-income funds are index funds that invest primarily in debt securities, such as government and municipal bonds. These are good for a conservative investing strategy.

If you're open to some risk, you could choose an index fund that balances stocks and debt securities. For example, a fund that invests 75% in bonds and 25% in stocks would provide fixed income with some room for exposure to potential market growth.

Sector-Based and Thematic Index Funds

Sector-based funds focus on a particular sector of the economy, such as health care, technology or agriculture. Thematic funds zoom in on particular interests, such as clean energy, artificial intelligence, electric vehicles or gaming.

What sector-based and thematic index funds have in common is that they're less diversified and therefore tend to be more volatile than broad market funds. Investors might choose to put money in niche funds out of personal interest, but they're likely better off as a supplement to your portfolio, rather than your main investing strategy.

4. Compare Fund Costs

Beyond considering specific indexes to track, you should do a side-by-side comparison of the expense ratios, performance histories and turnover rates for index funds you're considering. Turnover is how often a fund buys and sells assets. High turnover rates mean more taxable events for investors.

5. Open a Brokerage Account

Choose a well-known brokerage with a reputation as a quality investment platform with good customer service. Many top brokerages offer full-service financial tools, including various types of investment accounts, wealth tracking, financial advising and other money management tools.

Compare brokerage fees to ensure you're getting a good deal. Many brokerages offer commission-free trading on index funds, which is ideal: Commissions and fees eat into your returns.

If you already have a retirement account through your workplace, you may not need to open a new brokerage account. You can invest in index funds through your 401(k) or individual retirement account (IRA).

If you're planning to invest in a standard brokerage account rather than a retirement account, you might still find it beneficial to open your standard account at the same brokerage that houses your retirement account. Some investors like to track their net worth by seeing their assets all in one place.

Once you pick a brokerage, follow their instructions to open an account. You'll typically need to provide identification documents and link to the bank you'll use to fund your account.

6. Purchase Index Funds

Next, fund your investing account by transferring money from your bank. You could complete a one-time transfer and use it to place orders of your chosen index fund. Follow instructions within your brokerage's website to complete the order. You'll need to navigate to the broker's trade entry form and enter the ticker symbol for the index fund you want to order.

Another strategy is to set up recurring transfers from your bank into your brokerage account. You can do this in tandem with setting up recurring index fund buy orders. This is a sound way to automate your investing strategy and achieve what's called dollar cost averaging, where you invest equal amounts over time and avoid trying to time market fluctuations.

7. Monitor Your Performance

The beauty of index investing is that it's perfect for a "set it and forget it" strategy. Index funds work well for investing passively over the long term, and this "boring" buy-and-hold approach can help you level-headedly ride out market fluctuations.

That said, it's smart to keep an eye on how your portfolio performs. Over time, you should rebalance your portfolio when necessary to ensure your asset allocation fits your current investment goals.

The Bottom Line

Rather than trying to beat the market, index funds typically aim to replicate broad market growth. By spreading out your investments across many different assets, such as stocks and bonds, you're less susceptible to the potential for downward swings in the value of an individual company's stock. Of course, an index fund's value goes up and down as its holdings fluctuate, so you aren't totally sheltered from market volatility.

If you need help coming up with an individualized financial strategy and choosing investments, consider reaching out to a financial advisor. They can help you come up with a plan that best fits your situation and investing goals.