Referral Marketing for Eco-Friendly Challenger Brands

Ethical, sustainable and organic are more than trendy buzz words.

Concern for our planet is heavily influencing consumers’ buying decisions, from the clothes they wear, to what they eat and how they invest.

It’s not just millennials and Generation Z driving this shift to conscious capitalism – 49% of all consumers are more likely to recommend brands that address environmental concerns. 

But with more and more brands claiming (often dishonestly) to go green, it can feel tough to cut through the noise to acquire – and keep – target customers.

Against this backdrop, one marketing channel stands out as a way to cost-effectively grow your eco-friendly business: referral.

Here’s why refer-a-friend campaigns deliver remarkable results for eco-friendly challenger brands.

Why referral marketing is ideal for eco-friendly challenger brands

Referral marketing is a natural fit for sustainable, mission-driven brands. Why? Because customers who care deeply about values like environmental impact and ethical production love to spread the word.

Challenger brands thrive on authenticity and community—and nothing beats the authenticity of a recommendation from a friend. Whether it’s plastic-free packaging, plant-based ingredients, or carbon-neutral delivery, your existing customers are the perfect ambassadors to share what makes your brand different.

By giving them the tools and incentive to recommend your products, you amplify word of mouth in a way that feels organic, not salesy. Referral becomes an extension of your mission—fueling growth while staying true to your values.

The benefits of referral marketing for sustainable brands

For sustainability-focused brands, referral marketing offers a powerful, low-cost way to scale responsibly:

Targeted growth: Reach like-minded customers who are more likely to value your brand’s mission and become loyal fans.

• Lower acquisition costs: Referrals typically outperform paid channels on both conversion and spend—critical for newer brands with lean budgets.
• Higher LTV: Referred customers tend to spend more and stick around longer, delivering stronger lifetime value and retention.
• Stronger brand credibility: Recommendations from peers build trust faster than ads ever could—and create genuine advocates, not just customers.
• Mission alignment: Referral gives loyal customers a way to actively support your growth, reinforcing their connection to your purpose.

Recommending ethical businesses makes us look & feel good

Social capital is the biggest driver of referrals. More than getting a great discount, complimentary gift or free delivery, customers want to look good in front of their friends. That’s the psychology of referral.

And what looks better than caring about the planet?

By telling others about environmentally-friendly brands, we’re also telling them we’re in the know and doing our bit to make a difference. 

Plus, it’s an easy way to drive positive change. Taking on a zero-waste lifestyle feels daunting, but encouraging friends to cut down on single-use plastic with brands like Wild is straightforward. And it can cause a ripple effect far more powerful than anything you could achieve alone.

We build upon this with clients like allplants, OVO Energy and Frugi by adding an element of sustainability to their referral incentives. 

allplants, for example, ran a campaign vowing to plant a tree in Zambia for every successful referral. So its customers helped the planet in a number of ways: eating vegan, encouraging their friends to do the same, and adding a new tree to the world. Not bad for taking a few seconds to share a referral offer.

allplants vowed to plant a tree for each successful referral

Sustainability is topical and on-trend

There’s no avoiding it: conversation about climate change and sustainable living is everywhere. It’s both topical, permanently in the news and social media, and on-trend, with eco-friendly brands being the coolest way to shop.

Rather than despair at melting ice caps and burning rainforests, telling friends about environmentally-friendly brands makes us feel like we’re taking a small bit of action to positively contribute to the conversation.

It also provides a trigger for your brand to come up in conversation. Whether that’s watching the news, chatting about eco-friendly living, or telling someone your new dress is a rental piece from one of the many emerging clothes hire companies.

Everyday life triggers brand recommendations

There are now ethical and sustainable brands across every sector. Though some are more visible than others - red lipstick, for example, is more likely to spark a comment than your heating supplier - there’s still a strong chance of acquiring referred customers via less obvious topics of conversation.

Take Mooncup, for instance. While the thought of chatting about menstrual cups may make some people recoil with horror (looking at you, men), a significant proportion of the population get a period every month, and the taboo of talking about it is fading. In this context, a woman telling their friend about an environmentally-friendly period product they use is likely to stick. Even if the friend doesn’t convert to a new customer right away, their period arriving each month will act as a reminder (tapping into the stimuli part of driving successful referrals). The stats speak for themselves: around 50% of Mooncup’s business comes from word-of-mouth marketing.

Another sector that may not immediately spring to mind when considering sustainability is finance. Yet a number of emerging financial brands are rooted in this very consideration. tikr, for example, lets users easily invest in global companies that are both making a profit and solving social and environmental problems. 

Meanwhile, in the utilities sector, brands like bulb are making energy simpler, greener and cheaper - and has grown exponentially to become Britain’s biggest domestic supplier of renewable energy. 

There’s brands out there to make every part of our lives more eco-friendly. The trick is to get your brand’s message to the right people, at the right time. And referral can do just that.

Changing to sustainability-related imagery significantly increased &Keep’s referral share rate

Be a sustainable business in more ways than one

There’s undoubtedly a strong (and growing) appetite for sustainable living. By implementing a referral programme that encourages, tracks and rewards those customers recommending your brand to others, you can fuel long-term, sustainable growth. 

Unlike traditional or digital marketing campaigns, encouraging happy customers to spread word of your brand is cost-effective, with measurable return on investment and a lasting impact. An effective refer-a-friend programme will spark continuous organic growth as referred customers refer their friends, who refer their friends, who refer their friends… you get the idea.

Referred customers have 2x the lifetime value and are 3x more likely to recommend their friends than customers acquired via other channels.

Case studies: eco-friendly brands using referral marketing

Here are three eco-friendly brands that leverage referral marketing to drive profitable growth and maximise customer lifetime value. You'll find insights, quotes and stats to help guide your referral strategy:

1. Cheeky Wipes

• 3x more referral revenue than their previous provider
• 49% of referrals driven by the post-purchase page
• 19% of customers referred friends in January alone

 “We’re driving 3x more revenue with Mention Me than with our previous referral provider. Within seven months, we beat our annual referral target—and results are still improving as we optimise.”

— Helen Rankin, Managing Director

2. Wild

• Referral data used to build high-converting Klaviyo segments
• 13x higher return from referred customers compared to other channels
• Targeted post-purchase journeys driving repeat purchases and new referrals

“Mention Me and Klaviyo have transformed how we connect with our customers. We’re now able to deliver smarter, more relevant comms—and drive measurable results.”

— Charlie Bowes-Lyon, Co-founder, Wild

3. allplants

• 5x increase in engagement from referral-based audience segments
• Referral data fuels high-performing Klaviyo journeys
• Fastest ever onboarding to capitalise on rapid growth

“Referral now plays a key role in our acquisition and retention strategy. Mention Me helps us identify and reward our most passionate customers—and deliver experiences worth sharing.”

— Ellie Austin-Williams, Head of CRM at allplants

Conclusion

People genuinely want to make a difference. Your brand helps them do that. Our platform makes it easy for more people to discover it. What are you waiting for?

Sustainable challenger brands don’t just need growth—they need the right kind of growth. Referral marketing offers a powerful way to scale in a way that’s authentic, cost-effective, and community-driven.

At Mention Me, we’ve helped purpose-led brands like allplants and Wild turn their happiest customers into their most powerful marketing channel. If your brand is built on passion and purpose, referral could be the secret weapon you’ve been looking for.