ETFs are a great way for most Belgians to build their wealth and improve their financial future. But there are thousands of ETFs available in the market, and more are coming out every week. The problem is that not all ETFs are of the same quality and is especially true if you choose sustainability as a criteria. Some are poorly diversified, others are actually not that ESG-friendly, with others you'll pay a lot more taxes, or they're too expensive... That's why we carefully picked the best sustainable ETFs so you don't have to. At the same time, we'll also look at the pros and cons of sustainable investing with ETFs.

What's a sustainable ETF?

An ETF, or Exchange-Traded Fund (also called "tracker"), is a type of investment fund that you can buy on a stock exchange. A sustainable ETF is a type of ETF that focuses on investing in companies that meet certain criteria for environmental, social, and governance standards (abbreviated to ESG). These standards can include a wide variety of factors, such as a company's impact on climate change, its labour practices, or its board diversity. Sustainable ETFs let you align your investments with your personal values and beliefs, while also potentially reducing risk and improving long-term returns.

Why you should invest in sustainable ETFs

First of all, we think that ETF investing, whether in sustainable ETFs or not, is one of the best ways to grow your wealth. But with sustainable ETFs, you can even invest in companies that align with your values, and make a positive impact. What's great about sustainable ETFs:

  • They're low-cost
  • Your investments are diversified
  • They're rooted in the real economy
  • Buy and sell whenever you want
  • Possible to invest starting from low amounts
  • Your investments are aligned with your ethical values
  • Have a positive impact
  • Transparency
  • They're prepared for long-term success

They're low-cost

Index investors pay low fees because ETFs are very cheap to run. That's because most simply track an index. And it's simple for a fund provider to track an index: all that is required is buying the stocks in the index, and update when the index changes. It doesn't require expensive analysts or other specialists. This makes most ETFs significantly cheaper than the active fund the bank tries to sell you.

Your investments are diversified

One of the goals of index investing is to diversify as much as possible. Through diversification across many countries and sectors, you eliminate unnecessary risk. And you also benefit from the growth of the best companies in the world, not just the large German, French or American companies you know. By investing in as many companies as possible, you're almost sure of including the winners, namely the minority of stocks that are responsible for the majority of the returns.

They're rooted in the real economy

Most index funds invest either in stocks or bonds. Those are backed by real companies, with real factories, employees, intellectual property, and so on. This is unlike, for example, the crypto space, where the value of a currency or token is mostly determined by its potential rather than by concrete applications.

Buy and sell whenever you want

ETFs are very easy to buy and sell. If you wish to, you can trade any ETF within minutes. In finance jargon, we say that ETFs are "liquid". This is an advantage compared to other types of investments such as real estate or art. For instance, when selling a house, it can take a long time before finding the right buyer. As a matter of fact, a real estate ETF provides a more accessible way to invest in real estate than owning property directly.

Possible to invest starting from low amounts

An advantage with ETF investing is that you don't need a lot of capital to get started. You can even invest with as little as €50. This makes ETF investing possible for everyone, especially if you're young, just started your career and want to grow your wealth by putting your savings to work. In contrast, real estate is much less accessible. Just the down-payment for a property requires several tens of thousands of euros.

Your investments are aligned with your ethical values

Investing in sustainable ETFs you to align your investment choices with your personal values and principles. It gives you a real opportunity to support companies that prioritise sustainability, social responsibility, and ethical business practices.

Have a positive impact

Sustainable ETFs focus on companies that are actively addressing environmental social challenges. For example, in the portfolios offered through the Curvo app and managed by NNEK, there's a focus on one guiding principle: don't support companies that we consider destructive to the planet. In fact, sustainable companies have a slightly higher share price than their unsustainable competitors. This encourages sustainable practices within companies, as all companies want a higher stock price. Indeed, ESG investors settle for lower expected returns for companies they value for their sustainability principles. On the other hand, they demand higher expected returns from unsustainable companies. So by investing in these funds, you contribute to positive change.


Sustainable ETFs provide transparency regarding their ESG criteria and the companies included in their portfolios. They often disclose information on their holdings, ESG scores, and reports on impact metrics. This transparency allows you to make informed decisions and assess whether the fund aligns with your sustainability goals.

They're prepared for long-term success

Companies that prioritise sustainability and good governance practices are better positioned for long-term success. They are resilient to environmental and social risks and as such have a competitive edge. Investing in such companies through sustainable ETFs can potentially lead to long-term growth and returns.

Why you shouldn't invest in sustainable ETFs

There are also counter arguments against sustainable investing through ETFs. Let's unpack some of them.


Greenwashing refers to the phenomenon where companies present themselves as environmentally friendly or sustainable, when in reality they make limited efforts to meet ESG criteria. And "sustainable" ETF's can choose to include companies that engage in greenwashing. This way, you can be misled and invest in companies that are not really sustainable, without realising it.

For instance, DWS, a German asset manager and subsidiary of Deutsche Bank, was accused in 2022 of greenwashing. They invested the majority of its "green funds" in fossil fuel companies such as Shell and Total, despite promoting these funds as environmentally friendly, and investing only a fraction in renewable energy companies.

Unfortunately, it's difficult to be fully confident that an ETF is not involved in greenwashing. However, a bit of research can go a long way, by for instance looking into all the companies that the ETF invests in.

Lower (expected) return

We also saw above that the stock prices of sustainable companies are generally higher than non-sustainable stocks. Since companies want to maximise their stock price, this incentivises them to adopt better sustainability practices. But the flipside is that this negatively affects your returns as an investor. After all, more expensive shares mean lower expected returns.

Less diversification

ESG variants of ETFs exclude companies that do not certain sustainability criteria. This means that you are giving up some diversification. As a result, a portfolio of ESG ETFs will carry a bit more risk than its non-ESG version.

Higher costs

Selecting companies and monitoring their practices takes time, which reflects in higher ongoing costs. So sustainable ETFs tend to be more expensive than their non-ESG variant.

Lack of standards

Because sustainability is ultimately about ethical beliefs and values, it is by definition subjective. Therefore, you can argue endlessly about what the most sustainable investments are, never arriving at an objective answer that everyone can agree on. This is why sustainable investing lacks standardised criteria and definitions, making it challenging to compare and evaluate the sustainability practices of different companies.

We discussed at the pros and cons of sustainable investing. Let's now look at the best sustainable ETFs for Belgians to invest in.

The 5 best sustainable ETFs for Belgians

There are a few criteria to consider when choosing the best ETFs. Here’s a recap of the most important ones that we use in our selection.


Naturally, all ETFs that we select must have sustainability criteria that they apply to include companies in the fund.


In order to reduce the tax burden, it’s important that Belgian investors choose accumulating ETFs. As these funds directly reinvest their dividends, you won’t have to pay the 30% dividend tax.

Domiciled in Ireland or Luxembourg

Both countries have special tax treaties with many countries around the world. This makes it fiscally advantageous to invest in ETFs domiciled in Ireland or Luxembourg. You can recognise these by their ISIN code that starts with "IE" (Ireland) or "LU" (Luxembourg).

Traded in €

We only selected funds that are trading in Euro as we don’t want to pay unnecessary currency exchange fees.

Follows an index

The style of investing based on index funds, also called passive investing, is a superior strategy for most people. There’s no need to spend time analysing individual stocks, you can just follow an index of companies.


Most ETFs are already low-cost compared to active funds. But when we have the choice between several ETFs tracking the same index, we prefer a cheaper one (all other things being equal).

1) iShares MSCI World ESG (SNAW)

Index MSCI World ESG Screened
Ticker SNAW
Distribution policy Accumulating
Number of companies 1,406
Total expense ratio (yearly cost) 0.20%

The iShares MSCI World ESG Screened UCITS ETF, offered by iShares (a brand of BlackRock), tops our list. It tracks the MSCI World ESG Screened index, an index that consists of about 1,406 stocks from developed countries. The index excludes companies that are involved in businesses related to thermal coal, controversial weapons, tobacco and other controversial industries.

Investing in SNAW means investing in a wide segment of the global economy. Also, its underlying index has performed well historically.

2) Xtrackers MSCI World ESG (XZW0)

Index MSCI World Low Carbon SRI
Ticker XZW0
Distribution policy Accumulating
Number of companies 641
Total expense ratio (yearly cost) 0.20%

Second in our list is the Xtrackers MSCI World ESG UCITS ETF. It invests globally in companies with high sustainability scores and relatively low CO2 emissions. To be included in the SRI index, companies have to follow fairly strict criteria:

  • have a market capitalization of at least 10 billion dollars (this means only large companies are included!)
  • not being involved in controversial activities such as cluster munitions, landmines and bioweapons
  • not being active in the most polluting sectors such as mining
  • not have been involved in serious environmental controversies

Essentially, you're investing in 641 large companies through this ETF. The ETF is provided by Xtrackers, which is part of DWS and Deutsche Bank. Fortunately, they have not been doing greenwashing with this ETF (see above for DWS' greenwashing scandal).

Historically, the MSCI World Low Carbon SRI index has performed well:

3) Growth portfolio (accessible through Curvo)

Index FTSE Developed All Cap Choice
FTSE Emerging All Cap Choice
Distribution policy Accumulating
Number of companies 7,504
Number of countries 49
Total expense ratio (yearly cost) 0.28%
ISIN IE00B5456744

The Growth portfolio is a bit special because it's not a single ETF, but a portfolio of funds. It's available through the Curvo app is and is a popular combination for Belgian investors who wish invest sustainably in the global economy for the long term. Growth, along with the other portfolios, is managed by NNEK, a Dutch investment firm licensed by the Dutch regulator (AFM). It's composed of two funds, both offered by Vanguard:

  • A fund tracking the FTSE Developed All Cap Choice index (ISIN: IE00B5456744)
  • A fund tracking the FTSE Emerging All Cap Choice index (ISIN: IE00BKV0W243)

Through Growth you invest in over 7,500 companies and the portfolio has returned approximately 8.5% annually since 2005:

As we've earlier in the article, sustainable investing is challenging because everyone has different ethical beliefs and values. All the portfolios offered through the Curvo app and managed by NNEK (including Growth) focus on one guiding principle: they don't support companies that are considered destructive to the planet. This means the following sectors are excluded:

  • non-renewable energy (nuclear power, fossil fuels)
  • vice products (adult entertainment, alcohol, gambling, tobacco)
  • weapons (civilian firearms, military weapons)
  • controversial companies, which are companies that do not meet the labour, human rights, environmental and anti-corruption standards defined by the United Nations Global Compact

Automated savings plans

You can invest in the Growth portfolio in an automated way by setting up a monthly savings plan. Every month, the amount of your choice will be debited from your bank account and automatically invested for you in the portfolio.

No Belgian transaction tax (TOB)

There’s a tax on the transaction every time you buy or sell a security, called the transaction tax ("beurstaks" or "taxe boursière" or TOB). The rules concerning the tax rate are complicated, also for ETFs. Even brokers are confused because they use different tax rates for the same ETF. But contrary to all the ETFs listed here, there’s no transaction tax to be paid when investing through the Curvo app!

Fractional shares

You can buy fractions of the Growth portfolio. This means that all your money is invested for you. So if you invest €50 in Growth, the full €50 will be invested. Most brokers force you to buy units of stocks, with the consequence that you always have cash on the side not working for you.


The downside is the price. Depending on the broker and if you invest periodically, investing in one of the portfolios through the Curvo app can be more expensive than buying ETFs through a broker. The price starts from 0.6% “all-in” per year as a percentage of your total investments. But, it’s much easier than having to open a brokerage account and being yourself responsible for the management of your portfolio of ETFs!

4) iShares Edge MSCI World Minimum Volatility ESG (MVWE)

Index MSCI World Minimum Volatility ESG Reduced Carbon Target Index
Ticker MVWE
Distribution policy Accumulating
Number of companies 222
Total expense ratio (yearly cost) 0.35%

MVWE invests in 222 different stocks included in the MSCI World Minimum Volatility Index ESG. What is a minimum volatility index? The aim of a minimum volatility index is to provide investors with exposure to a basket of stocks that have historically exhibited less price fluctuations, thereby potentially reducing the overall risk of the investment. Essentially, stocks that fluctuate wildly are excluded. On top of that, MVWE is an ESG fund as it excludes all controversial, nuclear, tobacco, oil and coal companies. Examples of companies included in the ETF are Microsoft, Motorola and PepsiCo.

5) iShares Global Aggregate Bond ESG (AEGE)

Index Bloomberg MSCI Global Aggregate Sustainable and Green Bond SRI
Ticker AEGE
Distribution policy Accumulating
Number of companies 5,635
Total expense ratio (yearly cost) 0.10%

To round of our top five ETFs we felt it was important to feature a bond fund. All the ETFs we've seen up until now invest only in stocks.

The AEGE ETF (ISIN code IE000APK27S2) is a sustainable bond ETF popular among Belgian investors. This fund, launched by iShares in 2021 to track the performance of the Bloomberg Barclays MSCI Global Aggregate Sustainable and Green Bond SRI. The index only includes government bonds and corporate bonds that have been screened for ESG criteria. For instance, it excludes governments bonds issued by countries that have had UN sanctions applied. And for corporate bonds, it only includes the best issuers from an ESG and SRI perspective and excludes companies involved in controversial weapons, nuclear weapons, firearms, tobacco, adult entertainment, oil sands and others. On top of that, at least 10% of the fund is invested in green bonds, which are bonds specifically earmarked to raise money for climate and environmental projects.

Why have bonds in your portfolio

Whereas stocks are very exciting (and scary when they sharply drop), bonds are very boring. They don't fluctuate as much. So one way bonds are used in your portfolio is to tame the volatility of stocks. As Ben Felix explained in his interview with us, bonds are designed not to seek return, but to decrease volatility and stabilise a portfolio. Portfolios with more bonds relative to stocks will be better suited for investors with a lower appetite for risk. This means that going for a 100% stocks strategy or not should come in line with how smooth you wish your returns to be, to offset the potential impact of a downturn over your investment journey.

Beyond their role of stabilising a portfolio, bonds are also great diversifiers. It turns out that oftentimes when stocks are dropping, bonds are rising, and vice versa. So the losses of one type of asset can be partially offset by the gains of the other. In finance speak, we say that there is little correlation between stocks and bonds. You can learn more about bonds and their role in our piece on building a balanced portfolio of ETFs.

Also note that bonds held by Belgian investors are subject to the Reynders tax, which is 30% charged on capital gains. Yet this doesn’t outweigh the argument for holding bonds in your portfolio to stabilise your investments.

Comparison between the sustainable ETFs

Fund Asset Constituents Cost
MSCI World ESG (SNAW) Stocks 1.406 0.20%
Xtrackers MSCI World ESG (XZW0) Stocks 641 0.20%
Curvo Growth Stocks 7,504 0.29%
MSCI World Minimum Volatility ESG (MVWE) Stocks 221 0.35%
iShares Global Aggregate Bond ESG (AEGE) Bonds 5,635 0.10%

The challenges of managing your portfolio of ETFs

For many making their first steps into the world of investing, their bank is the one-stop shop for anything related to finance. Unfortunately, they are likely not your best partner when it comes to investing. They are simply a lot more expensive than the alternatives.

A better way is through a specialised service called a broker. Through a broker, you gain access to the financial markets where you can buy stocks, ETFs, bonds and even some more complex products like derivatives. However, brokers come with their challenges.

The allocation of your portfolio is in your hands

A single ETF does not necessarily make up a well-balanced portfolio. For instance, even though an ETF like VWCE is very diversified, not many investors are ready to emotionally withstand the high volatility of stocks. Also, if you invest for a shorter period of time, investing in just stocks is not the right strategy because you may not have enough time to recover from a downturn.

A balanced portfolio typically includes a mix of stocks, government bonds and corporate bonds to provide diversification and reduce risk. By investing in multiple asset classes, you achieve a balance between risk and return that aligns with their investment goals and risk tolerance. And when investing through a broker, you are responsible for finding the right mix for you.

You need to understand taxes

Taxes have an important impact on how you should invest. And unfortunately, taxes aren't simple in Belgium. But it's important you understand them if you are going to manage your portfolio of ETFs through a broker.

Requires discipline

Starting to invest is one thing. But it requires self-confidence and discipline to stay the course!

Brokers want you to trade

Research shows that a buy-and-hold strategy, where you hold your investments over a long period of time, delivers a higher return for most people than actively trading. The reason is that trading incurs taxes and transaction costs, which cut into your return. Additionally, it leads to taking investment decisions based on emotions, as well as reacting to short-term market fluctuations rather than taking a long-term investment approach.

But the business model of brokers is centred on trading. They need you to trade in order to generate revenue. That's why a broker like eToro has an inactivity fee, where they charge you $10 per month if you don't trade. Be careful with such brokers!

Curvo and sustainable ETFs

We understand that investing in ETFs through a broker can be daunting, especially for someone who's just starting to invest. We built Curvo to take away all the complexities of passive investing in ETFs and index funds. No need to search through thousands of ETFs or scour wikis in order to understand how to select a fund.

Invest sustainably

As we've seen in this article, investing sustainably is challenging because everyone has different beliefs and values. The portfolios offered through the Curvo app and managed by NNEK focus on one guiding principle: they don't invest invest in companies that we consider destructive to the planet.

Invest in a portfolio tailored to you

Based on a questionnaire, the right mix of funds is selected that corresponds to your goals and appetite for risk.

Get a better return on your time

Don't waste energy figuring out the intricacies of good investing. Open an account and spend your free time on the things that matter most to you.

Create an account in a few minutes using Curvo's app

Set up a savings plan

Put your savings on autopilot. Choose an amount and it will automatically beinvested every single month. Saving is easy when it's automated!

All your money is invested

In contrast with the majority of brokers, your investments through NNEK support fractional shares. This means that all your money is put to work. There will never be cash sitting on your account doing nothing.

No entry or exit fees

There are no transaction fees, entry or withdrawal fees.


We looked at the pros and cons of investing in sustainable ETFs. When then covered our selection of best sustainable ETFs for Belgian investors. We highlighted their historical performance, as well as their costs. We hope the list is helpful in making a choice! Whichever ETF you end up choosing, you’ve already made the right choice as ETFs are a great investment that provide diversification at a fairly low cost.

However, it can be intimidating to get started investing through a broker. There are quite a few questions you need to answer before you can start:

  • Which broker to choose?
  • What is the right mix of stocks and bonds for you?
  • Which mix of ETFs are best able to help you reach your goals?
  • What are the tax implications for each ETF in your portfolio?
  • … and more

This is where Curvo can help. After all, our goal is to take care of all the complexities of good and sustainable investing for you. Don’t hesitate to explore Curvo’s app.

Questions you may have

Is it wise to invest in ETFs?

Simple answer: yes it is! We believe that diversification is crucial when investing for the long term because it helps to reduce the overall risk of your investments. That's one of the reasons why ETF investing is so attractive. Investing in a single stock or asset class exposes you to the risks associated with that specific stock or asset class. If the company or industry experiences problems, your entire portfolio could suffer. That's why it's wise to invest in ETFs as it sets you up for long-term success.

Are there any sustainable ETFs part of DEGIRO's core selection?

There aren't too many of the popular sustainable ETFs which are part of DEGIRO's core selection of ETFs. But there are a couple:

  • VanEck Sustainable World (NL0010408704)
  • Rize Sustainable Food (IE00BLRPQH31)