How to Write Honest Sustainability Claims: A Copywriter's Guide
Here's the thing most marketers get wrong about the EU's greenwashing crackdown: they think it means they can't talk about the environment anymore. That's backwards. The ECGT doesn't punish environmental marketing — it punishes bad environmental marketing. Companies with genuine environmental achievements can still communicate them. They just have to be specific, honest, and evidence-based.
In fact, the ECGT creates an opportunity for good marketers. As competitors remove vague "eco-friendly" claims, specific and substantiated claims become more visible, more trusted, and more commercially powerful.
This guide is for copywriters, content marketers, and brand managers who need to write environmental claims that are both effective and legally compliant.
The Golden Rule: Specific Beats Vague, Every Time
Every compliant environmental claim has three components:
- What — the specific environmental attribute
- How much — quantified where possible
- Says who — the evidence source or certifier
"Eco-friendly packaging" has zero of these components. "Packaging made from 85% post-consumer recycled cardboard, certified by RecyClass" has all three. The second version is more compelling to informed consumers AND legally defensible.
Before and After: 15 Claim Rewrites
| # | Non-Compliant (Before) | Compliant (After) |
|---|---|---|
| 1 | "Eco-friendly product" | "Made from 90% recycled aluminium, ASI certified" |
| 2 | "Sustainable packaging" | "Packaging: 100% recyclable mono-material PP, RecyClass Grade A" |
| 3 | "Carbon neutral company" | "Scope 1+2 emissions reduced 42% since 2020 (verified by SGS)" |
| 4 | "Green energy" | "Powered by 12MW of on-site solar generation (operational since 2023)" |
| 5 | "Sustainable sourcing" | "100% of cocoa beans Rainforest Alliance certified since 2024" |
| 6 | "Environmentally friendly" | "Water consumption reduced 35% per unit since 2021 (ISO 14046)" |
| 7 | "Natural ingredients" | "92% ingredients from organic agriculture, COSMOS Natural certified" |
| 8 | "Zero waste company" | "98.6% manufacturing waste diverted from landfill in 2025" |
| 9 | "Climate positive" | "Net carbon removal of 500 tonnes via biochar programme (Puro.earth verified)" |
| 10 | "Conscious collection" | "Made with GOTS-certified organic cotton; low-water dyeing (60% less water)" |
| 11 | "Better for the planet" | "Carbon footprint: 1.8 kg CO₂e per unit (PEF methodology, verified)" |
| 12 | "We care about the environment" | "€2.3M invested in wastewater treatment upgrade; zero untreated discharge since 2024" |
| 13 | "Biodegradable" | "Biodegrades within 12 weeks under industrial composting (EN 13432 certified)" |
| 14 | "Reduced carbon footprint" | "Product carbon footprint: 3.2 kg CO₂e (2025) vs. 4.8 kg CO₂e (2022), per ISO 14067" |
| 15 | "Responsible business" | "B Corp certified (score: 89.3). Full assessment: bcorporation.net" |
Notice the pattern: every "after" version tells a more interesting story than the vague "before" version. Specificity isn't just legally required — it's better copy. "42% emissions reduction" is a stronger marketing message than "eco-friendly."
Words to Avoid (Black List Terms)
These terms, used without specific substantiation, are per-se ECGT violations:
- Eco-friendly / eco-conscious / eco-responsible
- Green / going green / green choice
- Sustainable / sustainability (as standalone claims)
- Environmentally friendly / environment-conscious
- Climate friendly / climate positive (without removal evidence)
- Nature-friendly / kind to the planet / better for the earth
- Carbon neutral / net zero (if based on offsets)
- Clean / pure (as environmental attributes)
You don't have to delete these words from your vocabulary. You have to ensure that every time one appears, it's accompanied by specific evidence. "Our sustainable approach" is banned. "Our sustainability achievements: 42% less energy, 35% less water, 90% waste diverted" is compliant.
Templates for Different Claim Types
Product Environmental Claims
Template: "[Product] [specific attribute] [quantity/percentage], [certification/verification]."
Example: "This jacket contains 80% recycled polyester (GRS certified) and uses PFC-free water repellent treatment."
Corporate Environmental Claims
Template: "We [specific action] [measurable result] between [start date] and [end date], [verified by/per methodology]."
Example: "We reduced Scope 1 and 2 emissions by 38% between 2020 and 2025, verified by Bureau Veritas per ISO 14064."
Progress Claims
Template: "[Metric] improved from [baseline] to [current], representing [percentage] improvement. [What remains to be done]."
Example: "Water consumption per unit decreased from 12.3 litres (2020) to 8.1 litres (2025), a 34% improvement. Our target: 5 litres by 2028."
Comparative Claims
Template: "[Percentage] less [metric] than [specific benchmark], measured per [methodology]."
Example: "30% lower carbon footprint than our 2020 equivalent product, measured per ISO 14067 with third-party verification."
Future Commitment Claims
Template: "Our target: [specific goal] by [date]. Current progress: [data]. Transition plan: [link]. Monitored by [independent body]."
Example: "Our target: 100% renewable electricity by 2028. Current progress: 62% (2025). Full transition plan: [sustainability report link]. Progress verified annually by EY."
Tone and Style for Honest Green Marketing
Be Direct, Not Defensive
Avoid hedging language that signals uncertainty about your own claims. "We believe our approach may help reduce environmental impact" sounds like a legal disclaimer. "We reduced water use by 35%" sounds like confidence.
Acknowledge Limitations
Counter-intuitively, admitting what you haven't achieved builds credibility. "We've made significant progress on Scope 1 and 2, but our supply chain emissions remain our biggest challenge — here's our plan" is more trustworthy than an unrealistically positive picture.
Lead with Data, Follow with Story
The most effective green marketing combines specific data with human narrative. The data provides substantiation; the story provides meaning. "We reduced emissions by 42% — here's how our engineers redesigned the manufacturing process" is both compliant and compelling.
Avoid Emotional Manipulation
"For our children's future" and "because we love our planet" are emotional appeals that add no substantiation. If your claim needs emotional language to be persuasive, the underlying substance may be insufficient.
The Pre-Publication Checklist
Before any environmental claim goes live:
- Does the claim contain a specific, verifiable element?
- Can I point to documented evidence that supports it?
- Does the claim accurately represent the scope of the evidence?
- Would an informed consumer's interpretation match what the evidence shows?
- If a regulator asked for substantiation, could I provide it within 48 hours?
If any answer is no, revise the claim before publishing. Run the page through our greenwashing checker for a final automated check.