Sustainability marketing means telling customers about the genuine environmental or social steps your business takes, and doing it in a way that is accurate, specific and backed up by evidence. It might be the packaging you use, how you source materials, how you cut energy use or how long your products last.

Done well, it builds trust with customers who care about these things. Done badly, it is greenwashing, and in the UK that now carries real legal risk. This guide explains what sustainability marketing is, what the rules say, and how small businesses can talk about their green credentials on social media and their website without overclaiming.

Sustainability marketing is about proof, not slogans

Marketing and sustainability used to sit in separate boxes. Now many buyers, from individual shoppers to large companies choosing suppliers, want to know how a business operates as well as what it sells. That creates an opportunity for small businesses, which often have simple, honest stories to tell: a local supply chain, a refill scheme, a repair service, a commitment to fewer deliveries.

Sustainability marketing covers:

• Product claims, such as recycled content, recyclability or durability
• Business claims, such as renewable energy, reduced waste or lower emissions
• Imagery and branding, including green colours, leaves, globes and words like “natural” or “eco”
• Certifications and memberships, such as recognised eco labels or industry schemes
• Your plans and targets, such as a commitment to cut emissions by a set date

The common thread is that every one of these is a claim, and claims need to be true.

Greenwashing is a legal risk, not just a PR one

Greenwashing means giving a misleading impression of how environmentally friendly a product, service or business is. It is often unintentional: a vague “eco-friendly” label on a website, a stock photo of a forest, or a claim copied from a supplier’s brochure without checking it.

In the UK, environmental claims are covered by consumer protection law and by the advertising codes enforced by the Advertising Standards Authority (ASA). The Competition and Markets Authority (CMA), the UK’s competition and consumer regulator, published its Green Claims Code in 2021 to explain how the law applies. It sets out six principles. Claims must:

1. Be truthful and accurate
2. Be clear and unambiguous
3. Not omit or hide important relevant information
4. Only make fair and meaningful comparisons
5. Consider the full life cycle of the product or service
6. Be substantiated, meaning you have evidence to back them up

The code itself is guidance rather than a law, but it reflects legal duties that already exist. If your claims do not meet these principles, you are likely to be breaking consumer protection law.

The DMCC Act gave the CMA teeth

The big change came with the Digital Markets, Competition and Consumers Act 2024, often shortened to the DMCC Act. Since April 2025 the CMA has been able to enforce consumer protection law directly, without first going to court. In practice that means it can:

• Decide for itself that a business has broken consumer law
• Order the business to change what it is doing
• Require compensation or other redress for customers
• Fine businesses up to 10% of global annual turnover, or £300,000 if that is higher, for serious breaches

The CMA began issuing fines under these powers in 2026. The early cases were about hidden fees and pricing rather than green claims, but misleading environmental claims fall under the same rules. In January 2026 the CMA also published further guidance making clear that responsibility for green claims runs right through the supply chain. If you repeat a supplier’s claim on your website or product listing, you can be responsible for it too. Honest mistakes are not a defence, although good processes can affect the level of any penalty.

Related reading: Sustainable Web Design: How to Build a Lower Carbon Website

Related reading: Top Sustainable Influencers in the UK for 2025: Leading the Green Movement

For a small business the message is simple: if you would struggle to prove a claim, do not make it.

How to talk about green credentials honestly

Be specific

Vague words such as “eco-friendly”, “green”, “sustainable” or “planet-friendly” are the most common problem. They suggest a product has no environmental impact at all, which is almost never true. Replace them with exactly what you mean: “made from 70% recycled cotton”, “delivered by electric van within Guildford” or “packaging can go in your household recycling”.

Keep the evidence on file

Before you publish any claim, make sure you can back it up. That might be a supplier certificate, an energy bill showing a renewable tariff, test results or your own records. Keep it somewhere you can find it quickly if a customer or regulator asks.

Tell the whole story

Do not highlight one green feature while hiding a bigger impact elsewhere. If your packaging is recycled but the product is flown in from overseas, a “low impact” claim would be misleading. Talk about the specific improvement instead.

Be careful with comparisons and future targets

“50% less plastic” needs a clear comparison: less than what, and measured how? Targets such as “net zero by 2030” need a credible, published plan behind them. Claims about carbon neutrality that rely mainly on offsetting are an area regulators look at closely, so say clearly how you reach the figure.

Watch your imagery

Images make claims too. Leaves, forests, green globes and recycling symbols on a product page imply environmental benefits. Use them only where the claim behind them is real.

Sustainability on social media and your website

Social media is where most small businesses talk about sustainability, and also where it is easiest to slip into vague language. Some practical habits:

• Show, do not just tell. A short video of your refill station or your new solar panels is more convincing than a caption saying you care about the planet.
• Give the detail in the caption. If you mention recycled packaging, say what percentage and what material.
• Link to a fuller explanation. A short sustainability page on your website lets you explain your claims properly and gives social posts somewhere to point.
• Be open about what you have not fixed yet. Saying “we are still working on our delivery emissions” builds more trust than pretending everything is perfect.
• Check reposted content. Sharing a supplier’s or partner’s green claims can make them your claims too.

On your website, keep product descriptions, category pages and your “about” page consistent. If a claim changes, for example a supplier switches materials, update it everywhere. Our social media management team checks claims like these before anything goes out on a client’s channels.

Claims done right, with generic examples

Risky claim	Better version	Why it works
“Our eco-friendly packaging”	“Our boxes are made from 100% recycled cardboard and can go in household recycling”	Specific material, specific benefit
“A sustainable café”	“We serve oat milk at no extra charge and compost all our coffee grounds”	Describes real actions, not a label
“Carbon neutral deliveries”	“Local deliveries within 10 miles are made by electric van”	States what you do without relying on offsets
“Kinder to the planet”	“Designed to last at least five years, with spare parts and repairs available”	Durability is a measurable benefit
“Green cleaning products”	“Refills available in store, so you can reuse the same bottle”	Clear, checkable and practical

Each better version is something a customer can understand and something you can prove. That is the test for every claim.

Frequently asked questions

What is the difference between sustainability marketing and greenwashing?

Sustainability marketing shares genuine, evidenced environmental steps clearly. Greenwashing creates a misleading impression, through vague wording, exaggeration, missing information or imagery that suggests more than is true.

Does the Green Claims Code apply to small businesses?

Yes. Consumer protection law applies to businesses of every size, and the CMA’s guidance is written for all businesses making environmental claims to consumers.

Can I still use the word “sustainable”?

You can, but only with clear explanation and evidence of what you mean. On its own it is too broad, so pair it with specifics or choose more precise wording.

Who enforces green claims rules in the UK?

The CMA enforces consumer protection law and now has direct fining powers under the DMCC Act. The ASA deals with complaints about advertising, and local Trading Standards teams also play a role.

Get your green story right

Your sustainability efforts deserve to be seen, and told honestly. We help small businesses across Surrey, Hampshire and beyond turn real actions into clear, compliant content for social media and their websites. Find out more about our social media management and digital marketing for small businesses, or get in touch to talk it through.