Short answer: An exchange-traded fund (ETF) is a basket of investments — usually hundreds of stocks or bonds — that you buy and sell on a stock exchange like a single share. One share of a broad-market ETF gives you instant diversification for as little as 0.03% a year in fees. For most beginners, a low-cost index ETF is the simplest way to start investing.
What an ETF actually is
An ETF pools money from many investors and uses it to buy a portfolio of securities: stocks, bonds, commodities, or a mix. Each share you buy represents a small slice of that whole portfolio. The U.S. Securities and Exchange Commission’s investor education site has a plain-English overview of how ETFs work.
The first ETF, the SPDR S&P 500 ETF (SPY), began trading in January 1993. By the end of 2025, there were 4,495 U.S. ETFs holding about $13.4 trillion, according to the Investment Company Institute — about 89% of it in index ETFs.
Most ETFs are index ETFs: they track a benchmark such as the S&P 500 or the total U.S. stock market. A smaller, growing group are actively managed ETFs, where a manager picks securities trying to beat a benchmark.
How an ETF works: price, NAV, and creation
You buy and sell ETF shares through a brokerage account, any time the market is open, at a price that moves during the day — exactly like a stock. A mutual fund, by contrast, trades once a day, after the market closes.
Behind the price sits the net asset value (NAV): the value of everything in the basket, divided by the number of shares. Price and NAV are usually close but rarely identical.
What keeps them close is creation and redemption. Large brokerage firms known as authorized participants can swap a basket of the underlying stocks for new ETF shares, or hand shares back for the stocks. If the price drifts above the value of its holdings, they create shares and sell them, pulling the price back down; if it drifts below, they do the reverse.
The main types of ETFs
- Stock ETFs track a stock index (S&P 500, total market), a sector, or a style (growth, value, small-cap).
- Bond ETFs hold government or corporate bonds and pay interest; they are the calmer half of many portfolios.
- Dividend ETFs focus on companies that pay regular dividends. See our JEPQ dividend calculator and QQQI dividend calculator for two popular dividend-focused ETFs.
- Leveraged and inverse ETFs aim for two or three times the daily return of an index, or the opposite of it. These are trading tools, not long-term holdings: the SEC notes a real case where an index gained about 8% over four months while a fund aiming for three times its daily return fell 53%.
What an ETF costs
The main cost is the expense ratio, an annual fee deducted from the fund’s assets. Broad index ETFs are famously cheap: the Vanguard S&P 500 ETF (VOO) charges 0.03% a year. In 2025, asset-weighted averages were roughly 0.14% for index ETFs and 0.43% for active ETFs, against 0.36% for index mutual funds and 1.02% for active mutual funds.
On $10,000, a 0.03% expense ratio costs $3 a year; a 1.00% fund costs $100 a year.
Verified example: $10,000 invested for 30 years at a 7% gross annual return, with the fee taken out each year.
- At a 0.03% expense ratio: $10,000 × 1.0697³⁰ = $75,485
- At a 1.00% expense ratio: $10,000 × 1.06³⁰ = $57,435
- Difference: $18,050 — on the same starting amount, the same market return
The fee is silently deducted from returns, never billed — which is why it is so easy to ignore, and so expensive to ignore. Our compound interest calculator lets you run the same comparison with your own numbers.
ETF vs mutual fund
ETFs trade all day on an exchange, like a stock; mutual funds trade once a day, after the market closes. ETFs typically charge 0.03%–0.20% for index funds, against 0.10%–1.00% for mutual funds, and you can buy one with the price of a single share, while mutual funds often require $1,000–$3,000 to start.
ETFs are also more tax-efficient: because they mostly exchange securities “in kind” rather than selling them for cash, they rarely distribute capital gains. In 2025, only about 7% of ETFs distributed capital gains, compared with about 52% of mutual funds — fewer surprise tax bills in a taxable account. Inside a 401(k) or IRA, there is no tax difference; see our guide to 401(k) vs IRA to decide which account to fund first. See also our VOO vs QQQ comparison.
How to buy your first ETF
- Open a brokerage account — a taxable brokerage account, an IRA, or a 401(k) if your employer offers one.
- Pick a broad index ETF — a total U.S. stock market or S&P 500 fund with an expense ratio under 0.10% is the usual starting point.
- Buy one share — most brokers let you buy fractional shares, so you can start with as little as $1.
- Keep buying on a schedule — see our guide to dollar-cost averaging.
Before buying, check the expense ratio and the number of holdings.
Frequently asked questions
Is an ETF a good investment for beginners?
Yes — a broad, low-cost index ETF is one of the best starting points for a beginner. One purchase spreads your money across hundreds of companies at some of the lowest fees in investing. The risk is market risk: your balance falls when the market falls, so an ETF only works if you can hold it through downturns.
Do ETFs pay dividends?
Yes, if the securities inside them pay dividends or interest. A stock ETF passes through the dividends its companies pay, usually quarterly; a bond ETF passes through interest monthly.
Can you lose money in an ETF?
Yes. An ETF is only as safe as what it holds. A broad stock-market ETF can fall 20% or more in a bad year — the S&P 500 fell about 18% in 2022 — and a sector or single-country ETF can fall much further. ETFs protect you from the risk of a single company failing, not from market losses.
How is an ETF different from a stock?
A stock is ownership in one company; an ETF is ownership in a basket of many securities. Buying one share of an S&P 500 ETF is roughly equivalent to buying tiny pieces of about 500 companies at once.