How CMA green claims rules shape ecommerce SEO copy

What to take away

Why CMA green claims rules reach your ecommerce SEO copy

A product page that says "eco-friendly" to win a search snippet is a commercial communication. UK consumer law applies to it just as it applies to a billboard. The Competition and Markets Authority (CMA) enforces rules against misleading actions and omissions.

If your ecommerce SEO copy implies a green benefit that the product does not deliver, the CMA can treat that as an unfair commercial practice.

Search engines reward clear, useful content. That aligns with the law. Vague, exaggerated claims may win clicks in the short term, but they also attract complaints and regulatory attention.

The CMA published its Green Claims Code in September 2021; its guidance is titled “Making environmental claims on goods and services”. It explains how businesses should make environmental claims. You can read the collection at Consumer protection guidance for businesses - GOV.UK.

The reach is not limited to the product description. Titles, bullet points, image alt text, category introductions and meta descriptions all form part of the claim. A phrase such as "100% sustainable" in a meta description is a claim. It must be true and capable of proof.

UK stores also face sector-specific rules. The CMA expects businesses to take reasonable steps to ensure claims are accurate. That duty sits with the content team as much as with the legal team.

See our guide to ecommerce SEO rules and ethics.

What counts as a misleading environmental claim on product pages

A misleading environmental claim is any statement that gives a false impression about the environmental impact of a product or business. It can be explicit, like "carbon neutral", or implied, like a green leaf icon with no explanation. The CMA looks at the overall impression, not just the words.

The most common risks on product pages include:

The CMA’s Green Claims Code sets out six principles for environmental claims:

If you cannot substantiate a claim, do not publish it. That applies to ecommerce SEO copy on product pages, category pages and anywhere else the claim appears.

A useful test is the "standalone" test. If a shopper saw only the claim, without the rest of the page, would they be misled? If yes, the claim needs rewriting or removing.

CMA guidance and the Digital Markets, Competition and Consumers Act

The Digital Markets, Competition and Consumers Act 2024 (DMCC Act) received Royal Assent in 2024. The consumer protection provisions, including the fining powers, commence on 6 April 2025. It updates the UK's consumer protection regime and gives the CMA direct enforcement powers.

Under the DMCC Act, the CMA can decide that a business has breached consumer law and impose fines without going to court.

Part 4, Chapter 1 of the Act sets out the unfair-commercial-practices regime, including provisions on fake reviews. Pressure selling is also addressed by consumer-protection rules, including the banned practices in Schedule 1 to the Consumer Protection from Unfair Trading Regulations 2008.

For ecommerce SEO copy, the key change is deterrence. The CMA can fine up to 10% of global turnover for serious breaches. That raises the stakes for green claims that cannot be backed up.

The DMCC Act sits alongside the Consumer Protection from Unfair Trading Regulations 2008, which already prohibit misleading actions and omissions. You can read the full text of the DMCC Act at Digital Markets, Competition and Consumers Act 2024.

The Consumer Protection from Unfair Trading Regulations 2008 remain in force and are the basis for many CMA actions. They ban 31 specific practices in Schedule 1. Examples include falsely claiming to be a signatory to a code of conduct, displaying a trust mark without authorisation, falsely claiming approval by a public or private body, and using paid editorial content to promote a product without making its commercial nature clear. The regulations apply to online traders, including those selling through marketplaces.

The full regulations are at The Consumer Protection from Unfair Trading Regulations 2008.

The CMA's consumer protection guidance explains how it interprets these rules for online practices. It covers price transparency, urgency claims and environmental claims. The guidance is not law, but it indicates how the CMA will enforce. Following it reduces risk.

For content teams, the practical takeaway is simple: every claim on a product page must be capable of substantiation.

ASA rulings on green and performance claims in online retail

The Advertising Standards Authority (ASA) regulates advertising claims in the UK, including online marketing. It publishes rulings on cases it has investigated. These rulings show how the ASA applies the advertising codes to environmental and performance claims.

You can search past decisions at Rulings - ASA | CAP.

The advertising codes themselves, including the CAP Code, set out the rules for all UK advertising. They apply to online ads, social media posts and website content that counts as advertising. The codes are at Advertising codes - ASA | CAP.

The CMA has also acted on green claims in online retail. In 2024, ASOS, Boohoo and George at Asda agreed undertakings after the CMA found that terms such as "eco" and "sustainable" across their product ranges were not substantiated. The outcome was a formal commitment to change how those products are described.

The ASA also looks at whether the basis of a claim is clear. If a product is described as "recycled", the ad should say what proportion is recycled and whether that refers to the packaging or the product.

Performance claims are also covered. If a product page says "saves 50% energy", the ASA expects evidence. The same applies to comparisons such as "the most efficient on the market". Without a clear basis, the claim is likely to breach the codes.

These rulings matter for ecommerce SEO copy because they show the standard that regulators expect. A claim that fails the ASA test is also likely to fail the CMA test. The difference is that the CMA can fine, while the ASA can require ads to be withdrawn and publish the ruling.

Writing ecommerce SEO copy that separates evidence from aspiration

Good ecommerce SEO copy for green claims starts with a clear separation between what you can prove and what you hope to achieve. Aspirations can be communicated, but they must be framed as goals, not facts.

For example, "we aim to be carbon neutral by 2030" is an aspiration. "This product is carbon neutral" is a factual claim that needs evidence.

Use a simple writing rule: if a claim cannot be checked, it should not be stated as fact. Instead, describe the action you are taking and the evidence you have. For instance, "made with 50% recycled polyester, certified by [scheme]" is specific and verifiable. "Eco-friendly" is not.

A worked example can help. Suppose you sell a reusable water bottle. You want to highlight its green credentials. An aspirational version might say: "The most sustainable bottle you can buy." That is a comparative claim that requires proof.

A compliant version might say: “Made from 90% recycled stainless steel. The packaging carries the appropriate On-Pack Recycling Label (OPRL) for its disposal route.” Use an OPRL label only where the packaging assessment supports it; kerbside acceptance varies by local authority.

When writing meta descriptions, avoid unqualified green terms. A meta description that says "Shop eco-friendly clothing" is a claim. If the clothing is not demonstrably eco-friendly across its life cycle, the description risks breaching the rules. Better to say "Shop clothing made from organic cotton" if that is true and certified.

See our article on ecommerce SEO UK regulations.

Performance claims, comparisons and substantiation files

Performance claims are statements about what a product can do, such as "lasts twice as long" or "uses 30% less water". These claims are subject to the same rules as environmental claims. Comparisons with other products must compare like with like and be based on evidence.

The CMA expects businesses to hold a substantiation file for any claim they make. This file should include the evidence, the method used to gather it, and the date. It should be kept for as long as the claim is used and for a reasonable period afterwards.

The file does not need to be published, but it must be available if the CMA asks.

A substantiation file for a performance claim might include:

For comparisons, the file should show the basis of the comparison. For example, if you claim your product is "more efficient than Brand X", you need test data for both products under the same conditions. If you cannot get that data, do not make the comparison.

The ASA also expects substantiation before an ad runs. In practice, this means you should not publish a claim until the evidence is in place. If you are unsure, leave the claim out. It is better to lose a keyword than to face enforcement.

See ecommerce SEO advertising rules.

Reviewing category pages and meta descriptions for claim risk

Category pages often carry broader claims than product pages. They may say things like "our most sustainable range" or "eco-friendly products for the whole home". These are claims and must be substantiated. The same applies to meta descriptions, which are part of the page's commercial communication.

A risk review should look at every claim on the page. Start with the H1 and the introductory copy. Then check the product tiles and any filter labels. For example, a filter called "green" implies that all products in that filter meet a green standard. If some do not, the filter is misleading.

Meta descriptions are often written by SEO teams and may not go through legal review. They need the same scrutiny. A meta description that says "Buy sustainable fashion" is a claim. If the fashion is not sustainable by a recognised standard, the description is risky.

Use the workflow in the next section as the checklist for category pages and meta descriptions. See our ecommerce SEO quality checklist.

A claim approval workflow for UK store content teams

A claim approval workflow ensures that every claim is checked before it goes live. It also creates a record that can be used if the CMA or ASA asks questions. The workflow should cover product pages, category pages, meta descriptions and any other content that makes a claim.

Here is a numbered workflow you can adapt:

The workflow should be documented and followed by everyone who writes ecommerce SEO copy. It is not just for legal teams. Content managers and copywriters are the first line of defence.

See ecommerce SEO disclosure policy.

Common questions