A green label looks reassuring, but is it true? If you are asking what is greenwashing: it is environmental claims that make a product or company look greener than the evidence supports. Ask what backs each claim up.
For the wider context behind green claims, start with our explainer on what is sustainability.
| Item | Value |
|---|---|
| Single UK anti-greenwashing law | None; rules are spread across existing regimes |
| Maximum CMA fine under the DMCCA 2024 | Higher of £300,000 or 10% of global turnover |
| CMA Supply Chain Guidance | January 2026 |
| Advertising Standards Authority status | Non-statutory regulator |
| Date the UK legal guide was last updated | 15 September 2026 |
These figures come from a law firm’s UK guide, Linklaters’ ESG Quick Guide on UK greenwashing rules. Rules and penalties can change, so check the source before you rely on them.
What greenwashing looks like in everyday marketing
Greenwashing rarely announces itself. It usually appears as a friendly-sounding phrase on a pack, an advert or a company website, with little to show what lies behind it.
Common warning signs include:
- Vague words such as “eco” or “planet-friendly” with no explanation of what they mean.
- A claim about one small feature that makes the whole product sound green.
- Company-wide promises with no clear steps, figures or dates.
- Green imagery, such as leaves and earth tones, doing the work that evidence should do.
- Claims that cannot be checked because no standard, method or report is named.
None of these proves a claim is false. They are prompts to look closer before you trust the label.
Why the UK has no single anti-greenwashing law
As of Linklaters’ guide, last updated on 15 September 2026, the UK does not have one single anti-greenwashing law. Instead, the framework for sustainability-related claims is built on existing consumer protection, advertising, misleading marketing, financial and corporate governance rules, as set out in the Linklaters guide.
That means a misleading green claim can be tested against several different rulebooks. Which one applies depends on who made the claim and where it appeared. The same guide also lists an Anti-greenwashing Rule from the Financial Conduct Authority (FCA) for the financial sector.
The guide adds that formal enforcement action and litigation for greenwashing have been relatively limited in the UK so far. It also says the landscape is evolving rapidly.
What the CMA and the ASA can do
The Competition and Markets Authority (CMA) is the main consumer regulator in this area. Under the Digital Markets, Competition and Consumers Act 2024, it can enforce unfair commercial practice rules directly, without going to court. According to the Linklaters guide, that includes fines of up to the higher of £300,000 or 10% of global turnover, plus compliance and consumer redress directions.
The CMA also publishes a Green Claims Code, which sets out principles for environmental claims. The Advertising Standards Authority (ASA) works differently: it is a non-statutory regulator, and the guide says it has issued frequent rulings requiring advertisements to be removed in recent years.
How to check a green claim yourself
You do not need a legal background to test a claim. A few plain questions will catch most weak ones.
- Read the exact wording. Does the claim cover the whole product, only part of it, or the company in general?
- Look for a specific, measurable statement rather than a feel-good adjective.
- Check whether the claim names a standard, report or method you can look up.
- Ask whether the claim covers the whole journey of the product or only the most flattering stage.
- Compare how the same company talks about its wider impact, not just this one item.
The fourth question is the idea behind a life cycle assessment, which looks at impacts across a product’s whole life. When a claim is about emissions, it helps to know how a carbon footprint calculation is built, because the boundaries chosen can change the result.
What businesses that repeat claims should know
Responsibility does not stop with the company that first made a claim. The CMA’s Supply Chain Guidance (January 2026) clarifies that retailers, brands and suppliers across the supply chain bear responsibility for claims they repeat or pass on, as the Linklaters guide explains.
In practice, copying a supplier’s green wording onto your own product page without checking it is a risk. Keep the evidence behind every claim, and drop any wording you cannot support.
Frequently asked questions
Is greenwashing illegal in the UK?
Show answer
There is no single anti-greenwashing law. As of the Linklaters guide updated on 15 September 2026, misleading green claims are tackled through existing consumer protection, advertising, financial and corporate rules.
How big can a fine for misleading green claims be?
Show answer
Under the Digital Markets, Competition and Consumers Act 2024, the CMA can issue fines of up to the higher of £300,000 or 10% of global turnover, according to the Linklaters guide. Check the source for any later change.
Can a shop be responsible for a claim its supplier made?
Show answer
Yes, it can. The CMA’s Supply Chain Guidance (January 2026) says businesses across the supply chain bear responsibility for claims they repeat or pass on.
Who can get a misleading advert taken down?
Show answer
The ASA, a non-statutory regulator, has issued frequent rulings requiring advertisements to be removed in recent years, as reported in the Linklaters guide.
