Fundamentals
What is an ETF?
An Exchange-Traded Fund is a single tradable share that holds dozens or hundreds of companies inside it. One purchase, one ticker, broad market exposure, and you can buy or sell it during market hours like any stock.
6 min read
The idea, in one paragraph
An Exchange-Traded Fund, or ETF, is a basket of investments wrapped inside a single share that trades on a stock exchange. When you buy one share of an ETF that tracks the S&P 500, you are buying a fractional piece of all 500 companies that index contains, in roughly the proportions the index defines. The ETF provider does the bookkeeping for you, and you trade in and out as easily as you would trade Apple or any other stock.
The two important properties follow from that simple structure. First, you get diversification on day one. A single ETF share spreads your money across dozens or hundreds of companies, so the success or failure of any one of them barely moves your portfolio. Second, you trade during market hours at a continuously updated price, the way you would trade a stock. Unlike traditional mutual funds, which only price once a day at market close.
Most ETFs are physically replicated, meaning the fund actually owns the underlying shares. A few are synthetic, holding swap contracts with a bank that promise to deliver the index's return without owning the underlying stocks; this introduces counterparty risk and is more common in Europe than in the US. For our purposes, treat the standard case as physical replication, and treat the ETF as a thin wrapper around the basket of companies inside it.
X-Ray: see what's inside one share
Pick an ETF and see its top 25 holdings, sized by weight, grouped by sector. The point: one share is exposure to many companies across many sectors, diversification you would otherwise have to assemble one stock at a time.
Five things to remember
- One share is exposure to many companies. SPY's single share spreads your money across more than 500 firms; QQQ across about 100 of the largest non-financial Nasdaq names. The diversification is built in. You do not have to assemble it.
- Lower costs than mutual funds. The ongoing fee, called the Total Expense Ratio (TER), is typically 0.03% to 0.20% per year for broad-market ETFs, a fraction of what an actively managed mutual fund usually charges.
- Trades intraday. Unlike a traditional mutual fund, you can buy or sell an ETF at any moment during market hours at the live price. This is helpful when news breaks; it is also helpful when it tempts you to overtrade.
- Variants exist for almost any thesis. Sector ETFs, single-country ETFs, dividend-focused ETFs, factor ETFs, currency-hedged ETFs, bond ETFs. The wrapper is identical; the underlying basket is what varies.
- Tax treatment varies by your country of residence. A Mexican investor pays different withholding on US dividends than a Brazilian one; a Chilean investor faces different reporting rules than a Peruvian one. Confirm the local tax handling for foreign-asset investing before scaling positions.
Why this matters for LATAM investors
For investors in Mexico, Brazil, Colombia, Peru and Chile, ETFs are the standard vehicle for getting exposure to the US and global markets without owning individual foreign stocks one ticker at a time. Most LATAM brokers (Bitso, GBM+, XP, Avenue, BTG Pactual, Modal, Fintual, BICE) give retail clients direct access to the major US ETFs at modest commissions, often zero on a few headline names.
The wrapper matters here for a second reason: most ETFs of interest are denominated in US dollars. Buying VOO from a Brazilian or Mexican broker gives you exposure to both the underlying companies and to the dollar, historically a useful hedge against local-currency depreciation. Combined with long-term compound growth, an ETF is one of the simplest ways for a LATAM household to participate in global market returns without picking individual foreign stocks.
ETFs to compare side by side
Four widely-held ETFs that capture the broad US market through slightly different lenses. Use them as starting points for your own research, not recommendations.
Where to start
If the idea makes sense and you want a curated shortlist, our ETF starter selection picks low-cost, diversified funds across global, dividend and core US exposure.