Investing Guide: ESG and Sustainable Investing in the UK — How to Invest Responsibly in 2025/26

ESG stands for environmental, social, and governance — three broad categories used to assess how a company manages risks and opportunities beyond traditional financial metrics.

Environmental factors include carbon emissions, energy efficiency, waste management, water use, and exposure to climate-related risks. A company heavily reliant on fossil fuels, for example, faces both regulatory risk (tightening emissions targets) and transition risk (shifting consumer demand).

Social criteria look at how a firm treats its workforce, supply chain, and communities. This covers labour standards, diversity and inclusion, data privacy, product safety, and human rights practices.

Governance examines board structure, executive pay, shareholder rights, audit quality, and anti-corruption policies. Poor governance has been at the heart of numerous corporate scandals — from accounting fraud to excessive risk-taking.

For investors, ESG analysis serves two purposes. First, it helps identify companies that may be better managed and more resilient over the long term. Second, it allows you to direct capital towards businesses whose practices align with your personal values. These two motivations are not mutually exclusive — indeed, a growing body of academic research suggests that companies scoring well on ESG metrics tend to exhibit lower volatility and fewer tail risks, even if the return premium remains debated.

It is worth noting that ESG investing is not the same as ethical or impact investing, though the terms are often used interchangeably. Ethical funds typically exclude entire sectors (tobacco, weapons, gambling), while ESG funds may still hold companies in those sectors if they score well on governance or environmental metrics. Impact investing goes further, targeting measurable positive outcomes — such as affordable housing or clean energy deployment — alongside financial returns. Understanding these distinctions is important when choosing a fund, as the label on the tin does not always match what is inside.

The UK market now offers a broad range of ESG funds across three main categories. Here is a practical overview of what is available.

ESG Index Funds and ETFs

For cost-conscious investors, ESG index trackers provide broad market exposure with screens applied to remove or underweight controversial companies. Popular options include:

• Vanguard ESG Global All Cap UCITS ETF (V3AM) — ongoing charge of 0.24%, tracks the FTSE Global All Cap Choice Index, excludes fossil fuels, vice products, weapons, and companies breaching UN Global Compact principles
• iShares MSCI World SRI UCITS ETF — ongoing charge of 0.20%, selects the top 25% of ESG-rated companies in each sector from the MSCI World Index
• HSBC FTSE All-World ESG Index Fund — ongoing charge of 0.17%, available on most UK platforms, tilts towards higher ESG scores rather than hard exclusions
• L&G Future World ESG UK Index Fund — ongoing charge of 0.15%, tracks a UK-focused ESG-tilted index

These funds typically cost only 0.05–0.10% more than their non-ESG equivalents — a modest premium for the screening involved. For more on low-cost index investing, see our guide to index funds and ETFs.

Actively Managed ESG Funds

Active ESG funds employ dedicated analysts to assess sustainability factors alongside financial fundamentals. Notable UK-available options include:

• Royal London Sustainable Leaders Trust — a long-standing UK equity fund with a strong track record, ongoing charge around 0.78%
• Liontrust Sustainable Future Global Growth — invests in companies addressing sustainability themes, ongoing charge around 0.85%
• Baillie Gifford Positive Change Fund — focuses on companies contributing to social or environmental solutions, ongoing charge around 0.52%
• Stewart Investors Worldwide Sustainability Fund — emphasis on quality companies in emerging and developed markets, ongoing charge around 0.85%

Active funds charge more but can offer deeper ESG integration and engagement with company management. Whether the higher fees translate into better outcomes depends on the individual fund — past performance, as always, is not a reliable guide.

Multi-Asset and Ready-Made ESG Portfolios

For beginners who want a single-fund solution, several providers offer ESG-screened multi-asset portfolios. Wealthify, Nutmeg, and Vanguard's LifeStrategy range (though not explicitly ESG-labelled) provide varying degrees of sustainable tilting. Platforms like Clim8 Invest focus exclusively on climate-themed investments.

One of the most common questions about ESG investing is whether it costs you returns. The evidence from the past five years paints a nuanced picture.

During 2020 and 2021, many ESG funds outperformed their conventional benchmarks. This was partly driven by the strong performance of technology stocks (which tend to score well on ESG metrics) and the underperformance of fossil fuel companies during the pandemic. The MSCI World SRI Index returned approximately 22.4% in 2021, compared with 21.8% for the standard MSCI World — a modest but positive gap.

However, 2022 told a different story. The energy crisis triggered by Russia's invasion of Ukraine sent oil and gas stocks soaring — sectors that most ESG funds had excluded or underweighted. The MSCI World SRI Index fell roughly 18.5% that year, compared with a 12.8% decline for the broader MSCI World. ESG investors effectively missed the energy sector's rally.

Since then, performance has converged. Over the three years to December 2025, global ESG indices have tracked within 0.5–1.0 percentage points of their parent indices on an annualised basis — a gap that falls within the range of normal tracking difference for any screened index.

The key takeaways from the performance data are:

1. ESG funds are not a guaranteed route to outperformance — nor do they systematically underperform. Over the long term, returns have been broadly comparable.
2. Sector concentration matters. ESG screens that exclude entire industries (energy, mining) create sector biases that can help or hurt in any given year.
3. Fund selection is critical. The gap between the best and worst ESG funds is far wider than the gap between ESG and non-ESG indices. Choosing a well-constructed fund with low costs matters more than the ESG label itself.

As the MoneyHelper guide to ethical investing notes, investors should focus on their long-term goals and risk tolerance rather than short-term performance comparisons.

The UK's Financial Conduct Authority has taken significant steps to bring clarity to the sustainable investment market. The Sustainability Disclosure Requirements (SDR), introduced from November 2024, represent the most important regulatory change for ESG investors in recent years.

The Four SDR Investment Labels

Fund managers authorised in the UK can now apply one of four labels to qualifying products:

• Sustainability Focus — invests in assets that are already environmentally or socially sustainable, as measured by a credible standard
• Sustainability Improvers — invests in assets that may not yet be sustainable but where the fund manager aims to drive measurable improvement over time
• Sustainability Impact — targets measurable positive environmental or social outcomes alongside financial returns, typically through newer or smaller enterprises
• Sustainability Mixed Goals — combines elements of the above approaches within a single fund

These labels are voluntary, but funds that use them must meet strict criteria, including clear sustainability objectives, ongoing measurement and reporting, and independent verification. Crucially, funds that do not qualify for a label cannot use sustainability-related terms (such as "green", "ESG", or "sustainable") in their marketing materials — a direct anti-greenwashing measure.

What This Means for Investors

The SDR labels give UK investors a much clearer framework for comparing funds. Before SDR, terms like "sustainable" and "responsible" had no standardised meaning, making it difficult to distinguish genuine ESG integration from superficial marketing. Now, if a fund carries a label, you can be confident that the FCA has scrutinised its approach.

However, it is worth noting that many perfectly good ESG funds may choose not to apply for a label — particularly if their strategy does not fit neatly into one of the four categories, or if the compliance costs are prohibitive for smaller fund managers. The absence of a label does not mean a fund is greenwashing; it simply means it has not been through the SDR labelling process.

Beyond Labels: The Anti-Greenwashing Rule

Separately, the FCA's anti-greenwashing rule (effective from May 2024) applies to all FCA-authorised firms — not just those seeking SDR labels. Any sustainability-related claim made in marketing must be fair, clear, and not misleading. This applies to factsheets, advertisements, and even social media posts. The rule has already led several fund managers to quietly rename or reclassify products that previously used sustainability language without robust backing.

[[CHART:pie|UK Sustainable Fund Market by SDR Label (Estimated, Late 2025)|Sustainability Focus:38,Sustainability Improvers:22,Sustainability Impact:12,Sustainability Mixed Goals:8,No Label (ESG-integrated):20]]

Building an ESG portfolio follows the same fundamental steps as any investment plan — with the added task of defining your sustainability preferences. Here is a practical roadmap.

Step 1: Clarify Your Values and Goals

Before choosing funds, decide what matters most to you. Are you primarily concerned about climate change? Labour rights? Corporate governance? Do you want to exclude certain industries entirely (negative screening), or would you prefer to invest in companies actively improving their practices (positive screening or engagement)? There is no right answer — but being clear about your priorities will help you choose the right funds.

Step 2: Choose a Tax-Efficient Wrapper

For most UK investors, the first port of call should be an ISA. The 2025/26 ISA allowance remains at £20,000, sheltering all investment gains and income from tax. If you have already used your ISA allowance, a pension (via a SIPP) offers even more generous tax relief. Investing outside a tax wrapper means gains above the £3,000 CGT annual exemption will be taxed at 18% (basic rate) or 24% (higher rate) from April 2025. For a detailed comparison of tax-efficient wrappers, see our guide to tax-efficient investing.

Step 3: Select a Platform

Most major UK investment platforms offer ESG funds. Vanguard, AJ Bell, Hargreaves Lansdown, interactive investor, and InvestEngine all provide access to ESG index funds and ETFs. Platform fees vary — typically between 0.15% and 0.45% of your portfolio value per year, plus the fund's own ongoing charge. For beginners, our guide to getting started with investing covers platform selection in detail.

Step 4: Build Your Portfolio

A simple ESG portfolio might consist of:

• Core holding (70–80%): A global ESG index fund or ETF, such as the Vanguard ESG Global All Cap or HSBC ESG All-World fund, providing broad diversification across thousands of companies
• UK tilt (10–20%): A UK-focused ESG fund if you want additional home-market exposure, such as the L&G Future World ESG UK Index
• Bonds or fixed income (10–20%): A green bond fund or ESG-screened corporate bond fund for lower volatility and income

This mirrors the structure you would use for any diversified portfolio — the ESG screening is applied on top of sound asset allocation principles.

Step 5: Set Up Regular Contributions

Pound-cost averaging — investing a fixed amount each month — smooths out market volatility and removes the pressure of trying to time your entry. Most platforms allow you to set up standing orders and automatic monthly investments from as little as £25.

Step 6: Review and Rebalance

Check your portfolio at least annually. ESG ratings change, fund strategies evolve, and your own priorities may shift. Rebalancing — selling overweight positions and topping up underweight ones — keeps your portfolio aligned with your target allocation. If your investments generate dividends outside an ISA, remember the £500 dividend allowance, with tax rates of 8.75% (basic), 33.75% (higher), or 39.35% (additional) on dividends above this threshold.

ESG investing is not without trade-offs. Here are the main considerations to weigh.

Costs

ESG index funds typically charge 0.02–0.10% more than their non-ESG equivalents. On a £20,000 ISA investment, this translates to roughly £4–20 per year in additional fees — a modest cost. Active ESG funds charge more (0.50–1.00%), but this reflects the active management approach rather than the ESG element specifically. Always compare the total cost — platform fee plus fund ongoing charge — when evaluating options.

Reduced Diversification

By excluding certain sectors or companies, ESG funds hold fewer constituents than broad market indices. The FTSE Global All Cap Index contains over 9,000 stocks; its ESG-screened version holds around 7,500. This is still highly diversified, but the exclusions create sector tilts that can affect performance in particular market conditions (as the 2022 energy crisis demonstrated).

Inconsistent ESG Ratings

Different rating agencies often disagree on the same company's ESG score. MSCI, Sustainalytics, and FTSE Russell use different methodologies, weightings, and data sources. A company rated "AA" by MSCI might score "medium risk" on Sustainalytics. This inconsistency flows through to funds: two ESG funds tracking different indices may hold very different portfolios despite both claiming to be sustainable.

The "Best-in-Class" Problem

Some ESG indices use a "best-in-class" approach, selecting the highest-scoring companies within each sector — including sectors you might expect to be excluded. This means an ESG fund could hold shares in an oil company if that company scores better on ESG metrics than its peers. If you want strict exclusions, check the fund's methodology carefully.

Transition Risk

The shift to a low-carbon economy creates winners and losers. Companies that fail to adapt may see their assets stranded, while those leading the transition may benefit. ESG funds aim to be on the right side of this shift, but the timing and pace of the transition remain highly uncertain.

Greenwashing Residual Risk

Despite the FCA's SDR labels and anti-greenwashing rules, no regulatory framework is perfect. Some funds may still overstate their sustainability credentials, particularly those operating outside the UK regulatory perimeter. Stick to FCA-authorised funds and look for SDR labels where available.

For a broader overview of investing principles, including asset allocation and risk management, explore our investing hub.

This article is for informational purposes only and does not constitute financial advice. You should seek independent financial advice before making any investment decisions.