How Marketplaces Can Use Sustainability Benchmarks to Help Shoppers Buy Better

Lessons from VoucherCodes’ World Sustainability Day Campaign

Sustainability is no longer a niche purchase consideration. Shoppers increasingly want to understand which brands are genuinely performing well environmentally — but they often lack a simple, credible way to compare them.

That is the gap VoucherCodes is addressing through its World Sustainability Day 2026 campaign with Earthmark. Rather than treating sustainability as a one-off marketing theme, VoucherCodes is spotlighting brands with strong environmental performance when benchmarked against relevant peers.

Featured brands include Crocs, Sephora, Cult Beauty and F&F, each highlighted through Earthmark’s 0–5 scoring.

The campaign demonstrates a practical model marketplaces can use to turn environmental data into shopper value, partner visibility and engagement around key calendar moments.

Explore the VoucherCodes World Sustainability Day campaign

Why VoucherCodes is well placed to do this

VoucherCodes is the UK’s most trusted voucher site, helping customers save £50m in 2025. With more than 8 million customers and partnerships with thousands of retailers and restaurants, both online and in-store, it sits at a influential point in the UK shopping journey.

That scale matters. Sustainability becomes more useful when it is surfaced where shoppers are already comparing offers, choosing brands and deciding where to spend.

VoucherCodes surfaces Earthmark ratings for more than 400 brands all year round. World Sustainability Day is therefore an amplification moment for an existing capability — not a standalone campaign.

Why sustainability needs to be comparable

Most shoppers do not want to read a 100-page ESG report before choosing where to buy. They want a clear answer to a simple question:

“Is this brand performing better than comparable brands on environmental issues?”

That requires more than a sustainability badge or a self-declared pledge. It requires:

• Consistent company-level environmental data

• A relevant peer group for comparison

• A simple score shoppers can understand quickly

• Clear sourcing and methodology

• Placement at the point of purchase decision

Earthmark is designed to make environmental performance more comparable. Brands are assessed using publicly available, company-level environmental data and benchmarked against peers, producing a 0–5 score.

For shoppers, this transforms abstract sustainability language into something more actionable.

What VoucherCodes is doing for World Sustainability Day

For World Sustainability Day 2026, VoucherCodes is spotlighting selected brands that achieve strong environmental performance relative to their peers.

The campaign features brands including:

The important point is not simply that these brands are featured. It is how they are featured: through a benchmarked environmental score, rather than unsupported green claims.

A repeatable marketplace playbook

This campaign is a strong example of how marketplaces can build sustainability into the shopping experience without disrupting the core commercial model.

The approach can be broken down into four steps.

1. Benchmark brands against relevant peers

A brand should not be assessed in isolation. A small independent retailer and a global multinational operate in very different contexts, with different data availability, supply chains and environmental exposure.

Effective benchmarking considers factors such as:

• Sector and sub-sector

• Company size and revenue band

• Geographic footprint

• Supply-chain complexity

• Available public disclosures

• Environmental materiality

This creates a fairer comparison and helps prevent high-performing smaller brands from being disadvantaged simply because they have fewer resources than global incumbents.

2. Translate complex data into a simple score

Environmental data is often detailed, technical and inconsistent. Shoppers need a simplified signal.

Earthmark’s 0–5 score provides that layer:

• 0–1 leaves: Limited environmental performance or disclosure

• 2–3 leaves: Emerging or moderate performance

• 4–5 leaves: Strong environmental performance relative to peers

The score does not replace detailed data. It makes it usable at the moment a shopper is deciding where to buy.

More information for each brand can be found on Earthmark's brand directory.

3. Curate offers around strong performers

VoucherCodes uses the benchmark to curate offers from brands scoring three leaves or above.

This is commercially sensible as well as sustainability-led. It gives shoppers a reason to engage with featured brands, while giving qualifying brands an additional route to visibility.

For marketplaces, this creates a new form of partner categorisation:

• Best offers

• New arrivals

• Trending brands

• Exclusive deals

• Strong environmental performers

Sustainability becomes part of the discovery experience, not a separate corporate-responsibility page.

4. Activate around calendar moments

World Sustainability Day provides a natural moment to amplify the framework. But the value comes from the fact that the benchmarking work is not limited to one day.

VoucherCodes already highlights strong environmental performers throughout the year. Calendar moments such as World Sustainability Day, Earth Day, Black Friday and seasonal shopping peaks can then be used to increase awareness and engagement.

This is the difference between a campaign and a capability.

The results show shopper and brand engagement

The approach is already delivering measurable engagement. Visits to VoucherCodes' Sustainability campaign page increased 186% after the addition of Earthmark in April 2025.

For a featured brand, VoucherCodes saw:

• An 80% increase in visits

• A 30% increase in average order value (AOV)

VoucherCodes also achieved a 78% click-through rate (CTR) for a VIP Earth Day campaign.

These results point to a clear commercial opportunity: when sustainability is presented as relevant, comparable and easy to act on, shoppers engage with it.

The benefit for shoppers

For shoppers, the benefit is clarity.

Instead of navigating vague claims such as “eco-friendly”, “conscious” or “better for the planet”, they can see a comparative environmental score based on publicly available company-level data.

That helps shoppers:

• Identify brands with stronger environmental performance

• Compare options within a category

• Make more informed purchasing decisions

• Avoid relying solely on marketing claims

• Support brands that are performing well relative to peers

It also makes sustainable shopping more practical. Shoppers do not need to become sustainability experts to make a more informed choice.

The benefit for brands

For brands, the benefit is credible visibility.

A strong Earthmark rating gives brands a way to demonstrate environmental performance using a consistent, benchmarked methodology — rather than relying only on self-declared claims.

This can help brands:

• Reach intent-led shoppers at the point of purchase

• Differentiate on substantiated environmental performance

• Earn placement in sustainability-led campaigns and curated collections

• Build trust with increasingly sceptical consumers

• Support green-claims communication with external benchmarking

• Create a commercial reason to improve disclosure and performance

Importantly, the rating is comparative. A brand is not simply rewarded for having a sustainability page; it is assessed against relevant peers.

For brands already investing in environmental performance, this creates a way to turn that work into discovery, engagement and commercial value.

The benefit for marketplaces

For marketplaces, sustainability benchmarking can become a genuine product and engagement layer.

It can support:

• Discovery: Help shoppers find better-performing brands

• Engagement: Give shoppers a reason to explore curated collections

• Partner value: Reward brands for strong environmental performance

• Differentiation: Position the marketplace as a more trusted place to shop

• Commercial activation: Build campaigns around sustainability-led moments

• Data maturity: Encourage better environmental disclosure across the partner base

The key is to keep the shopper experience simple. Marketplaces do not need to become ESG data platforms. They need to surface the right signal, in the right place, at the right time.

Why this matters for green claims

Consumer trust in sustainability messaging is under pressure. Regulators, including the UK’s Competition and Markets Authority, have increasingly focused on greenwashing and the need for environmental claims to be accurate, substantiated and clear.

Benchmarked insights can help address this by:

• Using defined methodologies

• Relying on publicly available data

• Comparing brands with relevant peers

• Making the basis of assessment visible

• Avoiding vague, unqualified claims

This does not remove the need for brands to communicate carefully. But it gives marketplaces and brands a more structured foundation for sustainability-led marketing.

The bigger opportunity

VoucherCodes’ World Sustainability Day campaign is a useful example of a broader shift:

Sustainability is moving from brand storytelling to decision-support infrastructure.

Marketplaces sit in a powerful position. They already influence discovery, comparison and purchase. By adding credible environmental benchmarking, they can help shoppers make better-informed choices while creating new value for high-performing partners.

The most effective approach is not to make sustainability the whole proposition. It is to make it a useful, visible and comparable part of the existing shopping journey.

That is what makes this campaign more than a World Sustainability Day activation. It is a template for how marketplaces can make environmental performance part of everyday commerce.

Explore the campaign:
VoucherCodes World Sustainability Day 2026

Get involved

Are you a brand with strong environmental performance — or a marketplace looking to make sustainability more comparable, engaging and commercially valuable?

Earthmark helps brands and marketplaces turn credible environmental benchmarking into shopper-facing visibility, curated campaigns and measurable engagement.

• Brands: Find out how your environmental performance compares with relevant peers and how a strong Earthmark rating could support visibility, trust and campaign participation.

• Marketplaces: Explore how to surface benchmarked sustainability data across your partner base and activate it around key retail moments.

Get in touch with Earthmark to start the conversation.