Which ETF Should You Choose? The 6 Major Indices by Profile

MSCI World, S&P 500, Nasdaq 100, STOXX Europe, CAC 40, emerging markets. Behind every ETF sits an index, and each index matches a different investor profile. Rather than drowning you in 200 references, here are the 6 indices that really matter in 2026, who each one suits, and the PEA-eligible ETF to access it.

Before you choose: one ETF = one index

You don't pick an ETF at random or by past performance. It tracks an index, that is a basket of companies defined by a rule. Choosing an ETF means first choosing which slice of the world you want to own: the whole world, the United States, tech, Europe, France, or emerging markets.

Second thing to understand: the more concentrated an index, the riskier it is. A World spread across 1,500 companies absorbs shocks better than a CAC 40 limited to 40 names or a Nasdaq overloaded with tech. Higher potential return is always paid for in volatility. Keep this risk versus diversification dial in mind for the 6 indices below.

The 6 indices to know (and which profile they fit)

1. MSCI World: the beginner's Swiss army knife

The global benchmark index: about 1,500 large companies across 23 developed countries (USA, Japan, Europe, Canada...). One purchase and you own a piece of Apple, LVMH, Toyota, Nestlé and 1,496 others.

• Who it's for: the beginner who wants one line, no decisions, and long-term investing without thinking about it. It's the default choice, and for 90% of people, the only one needed.
• PEA ETF: WPEA (iShares, ISIN IE0002XZSHO1, 0.20%) or DCAM (Amundi PEA Monde, FR001400U5Q4, 0.20%). CW8 (Amundi, 0.38%) is still an option if you already hold it.
• The limit: no emerging markets, and about 70% US exposure. Details in our MSCI World guide.

2. S&P 500: the bet on America

The 500 largest US companies. It's been the engine of global performance over the past 15 years, driven by US tech.

• Who it's for: someone who believes in lasting US dominance and accepts concentrating risk on a single country. Historically stronger than the World, but with no geographic safety net.
• PEA ETF: PSP5 (Amundi PEA S&P 500, ISIN FR0011871128, 0.12%) or ESE (BNP Paribas Easy S&P 500, FR0011550185, 0.14%, the most liquid).
• The limit: 100% USA, so full exposure to the dollar and the American economy. Compare it to the World in our S&P 500 vs MSCI World guide.

3. Nasdaq 100: the aggressive tech bet

The 100 largest non-financial companies listed on the Nasdaq, heavily dominated by tech (Apple, Microsoft, Nvidia, Amazon, Meta, Tesla...). The most dynamic mainstream index, but also the most nervous.

• Who it's for: the aggressive, young profile with a very long horizon, who accepts sharp swings (drops of 30 to 40% have already happened) in exchange for high growth potential. To use as a satellite, never as the sole core.
• PEA ETF: PUST (Amundi PEA Nasdaq-100, ISIN FR0011871110, 0.30%). It's the only PEA-eligible Nasdaq 100 in 2026.
• The limit: very concentrated in a handful of tech names. In a tech correction, it falls lower and faster than the World.

4. STOXX Europe 600: European exposure

About 600 large and mid-cap European companies (France, Germany, UK, Switzerland, Netherlands...). It's the broadest way to invest in Europe.

• Who it's for: someone who wants to reduce dollar exposure, rebalance toward Europe, or who finds US valuations too high. Useful alongside a World to overweight the old continent.
• PEA ETF: ETZ (BNP Paribas Easy STOXX Europe 600, ISIN FR0011550193). It's the only PEA-eligible STOXX Europe 600, because the physical versions hold UK and Swiss stocks (about 38% of the index) which make them ineligible.
• The limit: Europe structurally has fewer tech giants than the US, which weighs on long-term performance versus the World.

5. CAC 40: the bet on France

The 40 largest French companies (LVMH, TotalEnergies, Sanofi, L'Oréal, Air Liquide...). The index you see on the news every evening.

• Who it's for: someone who wants to bet specifically on French champions and likes their often generous dividends. More of a conviction or local complement choice.
• PEA ETF: Amundi CAC 40 (ISIN FR0013380607, 0.25%, accumulating). A distributing version also exists (FR0007052782) if you want dividends paid in cash.
• The limit: only 40 companies and heavy reliance on luxury and energy. Too concentrated to be a core holding on its own.

6. MSCI Emerging Markets: the bet on growth

The large companies of emerging countries: China, India, Taiwan, Korea, Brazil... These economies represent a huge share of expected global growth, completely absent from the MSCI World.

• Who it's for: the risk-tolerant profile with a 10-year-plus horizon who wants to capture emerging growth. It's the best "second ETF" alongside a World, far more relevant than a redundant S&P 500.
• PEA ETF: PAEEM (Amundi PEA Emergent MSCI Emerging, ISIN FR0013412020, 0.30%, accumulating).
• The limit: more volatile, exposed to political risk (notably China) and local currencies. Keep it to 10-15% max as a beginner.

Summary table

So, which profile are you?

Here's how to translate your profile into a concrete choice. Reminder: one or two lines are always enough.

• "I'm starting out, I don't want to manage anything": 100% MSCI World (WPEA). Full stop. It's the best choice for most people.
• "I want the whole world, emerging markets included": 85-90% MSCI World + 10-15% Emerging (PAEEM).
• "I believe in America": S&P 500 (PSP5) as the core, optionally a touch of Nasdaq for the aggressive side.
• "I want to back Europe / reduce the dollar": MSCI World + a STOXX Europe 600 (ETZ) or CAC 40 sleeve.
• "I'm aggressive and young": MSCI World as the base + a small Nasdaq 100 (PUST) sleeve, accepting the volatility.

The combination to avoid: stacking MSCI World + S&P 500 + Nasdaq. Since the World is already 70% American and packed with tech, you're just tripling the same dose. That's not diversification, it's a concentrated US bet in disguise.

How to choose an ETF (the 4 criteria that matter)

1. The index tracked: the most important point, and the subject of this whole article. First choose the slice of the world you want to own.
2. Fees (TER): between 0.12% and 0.40% for a good index ETF. Over 30 years, an extra 0.2% in fees costs thousands of euros. Avoid the 1.5% bank funds.
3. PEA eligibility: in a PEA, the ETF often needs to be synthetic to track a non-European index. All the ETFs listed here are. See our PEA vs CTO guide.
4. Accumulating vs distributing: to grow your capital without touching it, choose accumulating. Details in our dedicated guide.

What about taxes?

The choice of account matters as much as the choice of index. In 2026:

• PEA after 5 years: only 18.6% social charges on gains, exempt from income tax. It's the king account for eligible ETFs.
• CTO: 31.4% flat tax on capital gains, but access to all ETFs (including physical World funds and cheaper All-World funds).

For the full breakdown, see our PEA tax guide.

How to buy it in practice

1. Open a PEA with Trade Republic, Bourse Direct or BoursoBank. See our guide to opening a PEA.
2. Transfer the amount you want to invest (for example 200€).
3. Search your ETF ticker (for example "WPEA") in your broker's search bar.
4. Buy "at market" (simple order), or better, set up a monthly savings plan.
5. Set up a DCA and let it run. See our DCA guide.

Frequently asked questions