Sector ETFs: when betting on an industry makes sense — and when it doesn't

2026-05-31

In short: A sector ETF is a fund that invests not in the whole market, but in a single industry (technology or healthcare, for instance). They look tempting — especially when "their" sector has outpaced the rest of the market for several years. But for most beginners, broad global ETFs (like VWCE or IWDA) should remain the foundation of the portfolio, with sector ETFs as a maximum 5–15% "exploratory" slice. This article covers the five most popular sectors in Europe today: Technology, Healthcare, Clean Energy, Defence, and its opposite — ESG funds. No "where to invest" recommendations — just characteristics, pros, cons, and pitfalls.

What a sector ETF is and what it's for

When you buy an MSCI World ETF (IWDA) or FTSE All-World (VWCE), you get a piece of all the major companies on the planet — and these indices today are roughly 25–28% technology, 12–15% finance, 10–12% healthcare, and so on. The sector composition of a broad ETF is already balanced on its own, without your input.

A sector ETF does the opposite: it takes only one industry. For example, Xtrackers MSCI World Information Technology is only Apple, Microsoft, Nvidia, and about 70 more developed-market IT companies. No banks, no healthcare, no commodities.

Want to see real UCITS ETFs with actual performance data?

Open the ETF navigator

Why would anyone want this? Three typical motives:

"I believe this sector will grow faster than the market." For example, the conviction that AI and the cloud will make IT the main economic engine for another 20 years. In that case, "overweighting" IT through a sector ETF should deliver above-market returns.

"I want to invest in what I understand or what matters to me." Some people work in pharma and understand healthcare well; some care about the environment and want to back clean energy; others support the defence industry on principle.

"I want to take on more risk and potential return for a smaller amount." Sector ETFs are more volatile than broad ones — meaning they can deliver both larger returns and deeper drawdowns.

An important warning before we continue: the last motive is the most dangerous. "Higher returns through higher risk" works on average, but at any given moment you can end up in a bad stretch for 5–10 years. This is especially visible in the Clean Energy example below.

Now — the five sectors in turn.

1. Technology (Tech)

The most popular, the "hottest", and the riskiest at the same time.

What's inside: Apple, Microsoft, Nvidia, Alphabet, Meta, ASML, Salesforce, Oracle, and about 70–100 more developed-market IT companies. US concentration is usually 80%+.

Specific UCITS funds:

  • Xtrackers MSCI World Information Technology UCITS ETF (ticker XDWT, ISIN IE00BM67HT60) — TER 0.25%, accumulating. It uses a "20/35 cap" — a rule that no single company can occupy more than 35% of the portfolio, and all positions above 5% together cannot exceed 60%. This is important, because otherwise Apple + Microsoft + Nvidia would take up half of the entire fund.
  • iShares S&P 500 Information Technology Sector UCITS ETF (ticker IUIT, ISIN IE00B3WJKG14) — TER 0.15% (one of the cheapest thematic ETFs), accumulating, ~€16bn in size. The narrow version — only US tech, for those who believe in continued American leadership.

Pros:

The historical return of the IT sector over the last 10–15 years has been the best of any sector. It's the most "innovative" part of the economy — the revolutions of AI, cloud, and mobile platforms. The sector is well "understood" by beginners — everyone knows what Apple and Microsoft do.

Cons and risks:

Concentration. Even with the 20/35 cap, the fund holds a huge share in 5–7 companies. If something happens to one of them (an antitrust case, a bad quarter, a CEO departure), the fund will drop harder than the broad market.

Bubbles have happened and will happen again. The dot-com bubble of 2000: NASDAQ fell 78% and didn't recover until 2015 — fifteen years in the red. No one is saying that will happen now, but the IT sector is historically prone to overheating.

You're already in it through your broad ETF. In VWCE and IWDA, technology is 25–28% of the portfolio. If you buy a Tech sector ETF on top of a broad ETF, your IT share could become 50%+ — and that's no longer diversification, it's a bet.

Who it's for: for those who consciously want to overweight IT in their portfolio, understand the concentration risk, and are ready to hold the position for 15+ years in case of another bubble.

2. Healthcare

The most "stable" of the thematic sectors — and the most underrated by beginners.

What's inside: Johnson & Johnson, Eli Lilly, UnitedHealth, Novo Nordisk, Pfizer, Roche, Novartis, medical devices, pharmaceuticals, health insurance. Also US-concentrated (~65–70%), but not as heavily as Tech.

Specific UCITS funds:

  • Xtrackers MSCI World Health Care UCITS ETF (ticker XDWH, ISIN IE00BM67HK77) — TER 0.25%, accumulating, ~€3bn in size. Launched in 2016, so there's a reasonably long history.
  • iShares MSCI World Health Care Sector Advanced UCITS ETF (ticker WHCS, ISIN IE00BJ5JNZ06) — TER 0.18% (cheaper!), with ESG screening (excludes weapons, tobacco, fossil fuels). Makes sense if you want healthcare without side effects.

Pros:

Demographics — the ageing population of developed countries and China means growing demand for medicine for at least the next 30 years. This is a long-term structural trend, not a "fad".

Lower volatility than Tech. Healthcare companies pay dividends, generate steady cash flow, and in crises fall less than the broad market (people keep buying medicine even in recessions).

Less dependence on economic cycles. When the economy turns sour, Tech and Industrials suffer first. Healthcare last.

Cons and risks:

Regulatory risk — the main threat. Changes to the US health insurance system (Medicare, Medicaid), drug pricing reforms, patent restrictions — all of this can hit the sector hard. Against this backdrop, individual large companies can drop 10–20% in a week on a single piece of news.

US concentration. Even "World Health Care" is mostly the American pharma complex. If the US introduces strict price regulation, the fund will fall.

Hidden GLP-1 risk. Today, a large chunk of healthcare sector growth comes from Novo Nordisk and Eli Lilly with their diabetes/obesity drugs (Ozempic, Mounjaro). If competitors release more effective or cheaper versions, that's concentrated risk.

Who it's for: for those who want to add stability to their portfolio, believe in the long-term demographic trend, and aren't afraid of regulatory risk. Possibly the best "second ETF" after a broad World fund for a conservative investor.

3. Clean Energy

The disappointment sector of recent years — and a useful lesson about sector ETFs in general.

What's inside: solar and wind energy companies (First Solar, Vestas, Enphase), electric vehicle makers, hydrogen, lithium, renewable grid operators.

The specific UCITS fund:

  • iShares Global Clean Energy Transition UCITS ETF (ISIN IE00B1XNHC34, ticker INRG) — TER 0.65% (significantly more expensive than broad ETFs), distributes dividends semi-annually, ~£2.6bn under management. This is the largest and best-known Clean Energy fund in Europe.

Pros:

The energy transition is a real trend. The EU has set Net Zero by 2050, Germany has shut down its nuclear plants, investment in renewable sources is rising. On a 20-year horizon this sector should grow.

Ethically appealing — many people care about what they invest in, and Clean Energy is "investing with a conscience".

Cons and risks — serious ones:

Catastrophic drawdown 2021–2024. INRG peaked in early 2021 and then fell more than 60% by 2024. Those who bought at the peak are still in the red. The recovery is underway, but slow.

Strong dependence on interest rates. Clean energy companies are capital-intensive — they need huge investment in installations, so they suffer when rates are high (expensive financing). When rates rose in 2022–2023, the sector collapsed.

Political dependence. Subsidies, tax credits, tariffs — all of this is determined by politics. The change of administration in the US in 2024 has worsened expectations for the sector.

High TER (0.65%) — almost three times more expensive than broad ETFs. Over 20 years this will eat a noticeable chunk of returns.

Who it's for: for those who genuinely believe in the energy transition on a 20+ year horizon, are ready to survive deep drawdowns without panicking, and accept the higher TER. Not for "let me try to make money on a trend."

The Clean Energy lesson for beginners: even "correct" long-term trends have periods of 5+ years when they stagnate or fall. If you're not psychologically ready for this, sector ETFs aren't for you.

4. Defence

The hottest sector in Europe in 2024–2026, and at the same time the most ethically loaded. So an honest presentation: not "invest because it's rising", but "here are the data, decide for yourself".

What's inside: arms manufacturers (Lockheed Martin, RTX, BAE Systems, Rheinmetall, Leonardo, Thales), plus dual-use companies — cybersecurity, satellites, defence electronics.

Context for the growth: after 2022, European countries sharply increased defence budgets. Germany announced a €100bn special fund. The EU is discussing joint defence programmes. This led to an explosive rise in defence stocks: VanEck Defense ETF rose 68.8% in 2025.

Specific UCITS funds:

  • VanEck Defense UCITS ETF (ISIN IE000YYE6WK5, ticker DFNS) — TER 0.55%, accumulating, ~€7bn AUM. Global coverage — includes American, European, and Israeli companies.
  • HANetf Future of Defence UCITS ETF (ISIN IE000OJ5TQP4, ticker NATO) — TER 0.49%, ~€2.8bn AUM. Focused on NATO countries.
  • HANetf Future of European Defence Screened UCITS ETF (ISIN IE000I7E6HL0, ticker ARMY) — TER 0.39%, European defence companies only, SFDR Article 8 (i.e. with ESG screening: excludes manufacturers of banned weapon types — cluster bombs, mines, nuclear weapons).

⚠️ Ethical caveat.

By buying a Defence ETF, you're investing in companies that produce weapons. For some people this is fine (support for the defence capability of their country or its allies), for others it's unacceptable on moral or religious grounds. This is a personal decision, and Strean takes no position either "for" or "against". But we are obliged to highlight the fact: a fund showing good returns doesn't make the ethics question any less real. Settle it before buying, not during.

Pros:

A long-term trend after 2022 — European countries have set a course for rebuilding defence capacity, which will take at least 10 years. Order books at these companies are filled for years ahead.

Low correlation with the broad market. The defence sector often rises during periods of geopolitical tension, when other sectors fall. This gives the portfolio some protection.

Cons and risks:

Dependence on political decisions. One peace agreement — and the sector can turn down. What drives growth today (the war in Ukraine, the tensions) can end.

Already up sharply. +68.8% in 2025 is a lot. Buying now means buying after the main run-up. Prices may be "overheated" — that's the typical "chasing past returns" pattern.

High TER — 0.39–0.55% vs. 0.19% for broad VWCE. That's the price of a "narrow" structure.

ESG-filter ethical risk. If regulators or index providers introduce stricter ESG criteria in the future, you might end up with a fund that no longer fits "decent" portfolios.

Who it's for: for those who are consciously comfortable with the moral side, believe in the continuation of Europe's defence rebuild over 10+ years, and are prepared for high volatility on political news.

5. ESG / SRI — the opposite pole

Since we mentioned Defence, it's worth immediately showing its opposite — funds with ethical screening.

What ESG/SRI means: ETFs that exclude companies from certain industries or with low sustainability ratings. The acronyms: ESG (Environmental / Social / Governance), SRI (Socially Responsible Investing). In practice — they usually exclude tobacco, weapons, fossil fuels, gambling, and companies with serious ESG scandals.

Specific UCITS funds:

  • Xtrackers MSCI World ESG UCITS ETF (ticker XZW0, ISIN IE00BZ02LR44) — TER 0.20% (very cheap!), accumulating, ~€5bn in size. Tracks MSCI World Low Carbon SRI Selection — picks companies with the best ESG ratings and low carbon emissions (a double filter).
  • iShares MSCI World SRI UCITS ETF (ticker SUSW, ISIN IE00BYX2JD69) — TER 0.20%, accumulating, ~€10bn (one of the largest ESG funds in Europe). Tracks MSCI World SRI Select Reduced Fossil Fuel — excludes companies with low ESG ratings and major fossil-fuel producers.

Pros:

Pricing comparable to ordinary broad ETFs — TER 0.20%, almost like VWCE/IWDA. So the "ethical filter" doesn't cost much.

Returns are often close to the broad market. Years of research show: ESG funds deliver returns no worse than ordinary ones, sometimes slightly better, sometimes slightly worse — within statistical noise.

Alignment with values. If it matters to you not to invest in weapons and tobacco, this is a working way to invest "with a conscience" without major loss of return.

Cons:

"Greenwashing" is a real problem. Not all ESG funds are strict. Some are called "sustainable" but hold problematic companies. Read the index methodology, not just the name.

Less diversification. ESG filters exclude 30–50% of companies from the parent index. That's less diversification than a pure MSCI World.

Tilt toward Tech. ESG funds are often overweight technology (these have "clean" business models — no smoke, no commodity use). That means you get more Tech risk than you thought.

Who it's for: for those who care about investment ethics, are willing to accept slightly less diversification, and understand that "ESG ≠ moral purity" (it's just a filter by criteria).

The main rule for all sectors

If you take away just one thought from this whole article, let it be this:

Sector ETFs are not a replacement for a broad ETF, they're an addition to it. A typical sensible portfolio structure for a beginner:

  • 70–85% — a broad world ETF (VWCE or IWDA) — this is the core.
  • 5–15% — one or two sectors you want to overweight by conviction.
  • 0–10% — bonds/gold for stability.

And no more than 15% in sector ETFs total. Otherwise you turn your portfolio from "investing" into "betting", and concentration risk can disappoint you seriously.

Checklist: how NOT to pick a sector ETF

Don't pick by past returns. "This sector is up 50% this year — I'll buy it" is the worst possible strategy. Past returns are precisely what tells you the growth has already happened, and a correction is more likely ahead.

Don't pick just because of a "trending theme". AI, hydrogen, the metaverse, biotech — every year there's a new "next big thing". Most thematic ETFs launched at the peak of a fad underperform the broad market for 3–5 years afterward.

Don't buy small funds. Fund size below €100m means closure risk (the provider can liquidate an unprofitable fund, and you get tax consequences). Better to pick funds €500m and above.

Don't ignore the TER. 0.5% per year instead of 0.2% is 150% of 0.2% — that's 2.5 times more expensive. Over 30 years, that can eat tens of thousands of euros.

Don't buy more than 2–3 sectors. If you have 5 sector ETFs in your portfolio, you've effectively assembled your own mini-index — only worse and more expensive than a simple MSCI World. Less is more.

Bottom line

Sector ETFs are a tool for those who want to consciously skew the structure of their portfolio in one direction. They're neither "better" nor "worse" than broad ETFs — they're different. Their role is supplementary, not foundational.

If you're just starting to invest, our advice is simple: start with one broad world ETF (we have a separate article on the choice between VWCE and IWDA), and save sector ETFs for later, when you know your preferences. In a year or two, you'll know which industries interest you specifically, and can consciously add 10% here, 5% there.

And if you're already experienced — sector ETFs offer the chance to fine-tune your exposure: add Healthcare for stability, a bit more Tech for growth, ESG to align with your values, Defence if you're convinced about the long-term trend and accept the moral side.

Want to look at specific ETFs suitable for European investors, with honest data on returns and risks? Check out our ETF Explorer. And if you haven't yet decided on a portfolio allocation, take our short questionnaire — and get a personalised plan in 3 minutes.

This is educational material, not financial advice. Past returns do not guarantee future results. Before investing, consult a licensed financial or tax advisor — especially on questions of alignment with your personal situation and values.