How to Invest in the S&P 500

To invest in the S&P 500, you buy shares of a fund that tracks the index, usually an index mutual fund or an exchange-traded fund (ETF), through a 401(k), an IRA or a regular brokerage account. You can't buy the S&P 500 itself, because an index is just a list of companies; the fund owns those companies for you.

That makes the real decisions simpler than they look: which account to use, which kind of fund, what it costs and how often you'll buy. This guide walks through each one. It's education, not advice, and we don't recommend any specific fund. Investing involves risk, including loss of principal, and returns are never certain.

What are you actually buying when you invest in the S&P 500?

You're buying a small slice of about 500 of the largest US public companies, held through a fund. S&P Dow Jones Indices describes the S&P 500 as covering 500 leading companies and roughly 80% of the available US stock market value.

Three things about the index matter for a beginner:

• It's weighted by size. The SEC's index fund bulletin explains that many indexes use market capitalization (share price times shares outstanding) to set each company's weight. Bigger companies count for more, so a handful of giants can drive a large share of the index's moves.
• It's US large companies only. Small and mid-sized US companies, and every company outside the US, are left out.
• It changes over time. Companies are added and removed under the index provider's published rules, so what the fund holds shifts a little without you doing anything.

If you're still getting your bearings on how shares and exchanges work, our plain-English guide to how the stock market works covers the basics first. For where an S&P 500 fund fits among your first decisions, start with our investing for beginners guide.

What are the ways to invest in the S&P 500?

Most people use one of four routes, and they all end with you owning shares of an S&P 500 fund. The difference is the account wrapper and how the buying happens.

As of 2026, the IRS limit for employee contributions to a 401(k) is $24,500, and the IRA limit is $7,500, with higher catch-up amounts for people 50 and older. If your employer matches contributions, the workplace plan is often the first stop, provided it offers a low-cost S&P 500 or broad stock fund.

Robo-advisors usually build a mix of several funds rather than holding the S&P 500 alone; see our robo-advisors explainer for how their fees work.

Mutual fund or ETF?

Both can track the same index; they differ in how you buy them. A mutual fund is bought from the fund company at the end-of-day price and may have a minimum first purchase. An ETF trades on an exchange during market hours at whatever the market price is, and you need the price of one share, or less where your broker offers fractional shares. Our guide to index funds for beginners explains the wrapper differences and how to compare two funds in detail, so we won't repeat it here.

How do you invest in the S&P 500, step by step?

Pick the account, pick the fund, set an amount and automate it. Here's the order most beginners follow.

Step 1: Make sure the money is long-term money

The S&P 500 is entirely stocks. Investor.gov notes that large-company stocks as a group have lost money in about one out of every three years, and sometimes the losses have been dramatic. Money you'll need in the next few years usually belongs somewhere steadier, such as savings or short-term Treasuries.

Step 2: Choose the account

Use any employer plan with a match first, then a tax-advantaged account such as an IRA or Roth IRA if you qualify, then a taxable account. If you don't have a brokerage account yet, our step-by-step guide on how to open a brokerage account covers the application, and why you should choose a cash account rather than margin.

Step 3: Choose the fund

Look up the S&P 500 funds your provider offers. Check that the fund's name and documents say it tracks the S&P 500 itself, not a "500"-style index with different rules, a sector slice of it, or a leveraged or "buffered" version built with options. Those products behave very differently from a plain index fund.

Step 4: Decide how much and how often

You can invest a lump sum, a fixed amount every month, or both. Investor.gov describes dollar-cost averaging as investing equal amounts at regular intervals, regardless of market ups and downs, which means you buy more shares when prices are low and fewer when they're high. Setting up an automatic monthly purchase also removes the temptation to time the market.

Step 5: Choose what happens to dividends

Many S&P 500 companies pay dividends, which the fund passes on to you. Most providers let you reinvest them automatically, which buys more shares. In a taxable account, dividends are generally taxable in the year you receive them, even if reinvested; see how dividends are taxed for qualified vs ordinary rates.

How much does it cost to invest in an S&P 500 fund?

The fund's expense ratio is the main ongoing cost, but account fees and taxes can matter as much. S&P 500 index funds are among the cheaper funds available, but costs still differ between providers, so check each layer:

• Expense ratio: the annual fund cost, taken from the fund's assets. Find it in the fund's fact sheet or prospectus.
• Account or plan fees: some workplace plans and brokers charge administration or account fees on top.
• Trading costs: many brokers no longer charge commissions on ETFs, but the gap between buy and sell prices (the spread) is still a small cost.
• Advisory fees: a robo-advisor or adviser charges for managing the account.
• Taxes: none while inside a 401(k) or IRA; dividends and realized gains in a taxable account are taxed.

The SEC's index fund bulletin also warns that index funds can trail their index because of fees, trading costs and tracking error. When two funds track the same index, the SEC notes, the one with lower costs generally leaves you with a higher return.

Example (hypothetical): two funds track the S&P 500 and the index earns the same in both. One charges 0.05% a year, the other 0.50%. On a $10,000 balance, that's about $5 versus about $50 in a single year, and the gap compounds every year you hold.

What are the risks of investing only in the S&P 500?

An S&P 500 fund spreads your money across hundreds of companies, but it is still one slice of one country's stock market.

• Stock market risk: if US large-company stocks fall, the fund falls with them. There's no cash cushion and no manager moving to safety.
• Concentration: because the index is weighted by size, a small group of the largest companies can make up a big share of the fund. Check the fund's top holdings on its fact sheet.
• Country risk: everything is in US companies and US dollars. Many investors add international stocks.
• Size risk: small and mid-sized companies are missing. A total-market fund covers more of the US market.
• Behavior risk: the biggest danger is often selling after a fall. A written plan helps, and our list of beginner investing mistakes covers panic selling and timing the market.

Also know what account protection covers. SIPC protects up to $500,000, including $250,000 for cash, if a member brokerage fails and assets are missing, but it does not protect against a fall in the value of your investments.

Should the S&P 500 be your whole portfolio?

For some people it's the core of their stock holdings, but few portfolios stop there. Your mix depends on your goals, timeline and how much of a drop you could live through without selling.

A common approach is to treat an S&P 500 fund as one building block alongside bonds, cash for near-term needs and possibly international stocks. Investor.gov's asset allocation guide describes stocks, bonds and cash as the three main categories and explains why mixing them can reduce the impact of a bad year in any one. Our guide on how to build an investment portfolio walks through that process.

Can you invest in the S&P 500 from outside the US?

Usually yes, through locally available funds that track the index. The account rules are what change:

• UK: S&P 500 trackers are commonly held inside a stocks and shares ISA, a SIPP or a workplace pension. Some US-listed funds may not be offered to UK retail investors, so you'll often see UK- or Ireland-domiciled versions.
• Canada: through a TFSA, RRSP or non-registered account, using funds listed in Canada or the US.
• Australia: through ASX-listed funds via a broker, or through your super fund's investment options where available.

For investors outside the US, currency moves add a second layer of ups and downs: a rising US dollar lifts your returns in local terms, and a falling one cuts them. Withholding tax on US dividends can also apply; check your national tax authority's guidance.

Next steps

• If your money still needs a safety buffer, read emergency fund vs investing before buying any fund.
• Compare fund types and costs in index funds for beginners.
• Put the S&P 500 in context with our step-by-step guide to start investing.
• Or return to our guide to making money online to look at ways to grow the income you invest.