Advertising Standards Authority updates Guidance on Environmental Claims

The Advertising Standards Authority has published updated guidance on 10 February 2023 to include guidance on the use of environmental, sustainability, carbon neutral, net zero and so-called 'greenwashing' claims in advertising CAP-guidance-on-misleading-environmental-claims-and-social-responsibility.pdf ( . 

This reflects key principles of the Competition and Markets Authority’s guidance on environmental claims on goods and services (the CMA guidance) Environmental claims on goods and services (

Carbon Neutral & Net Zero Claims 

The ASA identified consumer understanding of “carbon neutral” and “net zero” claims in advertising as a priority area for research, given their increasing prevalence and the potential for consumers to be misled by them. This was particularly relevant due to the lack of consensus on the meaning of carbon neutral and net zero, the practice of offsetting and what was understood by this by consumers resulting in the need for greater transparency.

CAP and BCAP advise advertisers to take into account the following guidance, that, if followed, means claims are less likely to mislead:

  • Avoid using unqualified carbon neutral, net zero or similar claims. Information explaining the basis for these claims helps consumers’ understanding, and such information should therefore not be omitted.
  • Marketers should ensure that they include accurate information about whether (and the degree to which) they are actively reducing carbon emissions or are basing claims on offsetting, to ensure that consumers do not wrongly assume that products or their manufacture generate no or few emissions.
  • Claims based on future goals relating to reaching net zero or achieving carbon neutrality should be based on a verifiable strategy to deliver them.
  • Where claims are based on offsetting, they should comply with the usual standards of evidence for objective claims set out in this guidance, and marketers should provide information about the offsetting scheme they are using.
  • Where it is necessary to include qualifying information about a claim, that information should be sufficiently close to the main aspects of the claim for consumers to be able to see it easily and take account of it before they make any decision. The less prominent any qualifying information is, and the further away it is from any main claim being made, the more likely the claim will mislead consumers. For further information, see CAP’s guidance on the use of qualifications Guidance on the use of qualifications in ads - ASA | CAP.

The Codes make clear that absolute claims should be supported by a high level of substantiation.

'Absolute' Environmental Claims

Previous cases where substantiation has been deemed insufficient for absolute claims include:

  • “The greenest stoves on earth”
  • Claims that a waste carrier network could “Save CO2 emissions”
  • “Eco-friendly” claims for an instant boiling water tap • Offering 100% renewable energy to consumers “without harming your world”
  • Coffins being made from “100% recycled cardboard”
  • Claims for a recipe box, including “plastic-free”, “absolutely no plastic” and “100% plastic-free recipe box”, “100% recyclable” and “widely recycled”, which applied to the box itself and not its components

Absolute claims like “environmentally friendly” must only be made if the advertiser can demonstrate that the product or service has no detrimental effect on the environment, taking into account its entire lifecycle. 

Comparator Environmental Claims

Relative claims like ‘greener’ or ‘friendlier’ will require verifiable evidence that proves an environmental benefit over comparable products. Marketers should set out the relevant information in the ad or signpost how the information used to make that comparison can be checked by the target audience.

Lifecycle of Product

General claims should not be used without qualification unless marketers / broadcasters can provide evidence to demonstrate that the claim applies to the entire lifecycle of the product or service, from manufacture to disposal. 

Examples of general claims which are likely to be considered full lifecycle claims, unless stated otherwise include:

  • Good for the planet.
  • Good for the land.
  • Helping to support a more sustainable future.
  • 100% eco-friendly.
  • Environmentally friendly.
  • Zero emissions.
  • Give back to the environment.
  • Less plastic. 

Even where claims can be substantiated or are technically correct, ads must take care not to mislead consumers about the environmental benefit of a product or service.   the limits of the lifecycle must be made clear. More limited claims about a specific aspect of a product or service may be acceptable.

Where a claim relates only to part of a product or service’s lifestyle, this should be made clear. Ads must not mislead consumers about the product's total environmental impact. Examples given are:

  • A zero emissions claim may be acceptable when made about an electric vehicle, if the ad makes clear that the claim relates to driving only.
  • Where the farming methods used provide an environmental benefit over other farming methods, the ad must make clear that the claim relates to the farming method only.
  • If an advertiser has reduced the production of plastic packaging for part of a product, the ad must not imply an overall reduction in plastic waste for the whole product.

Level of Substantiation

If a 'significant' division of scientific opinion exists or evidence is inconclusive, that should be made clear to consumers. As to what is 'significant' the guidance simply references that 'marketers must be convinced that the relevant informed opinion is not divided' putting the onus on them to decide what this is.

Next steps

Claims in this area will be monitored for the next 6 months and information gathered on how such claims are being substantiated.  

In the meantime, the ASA will be taking proactive action immediately to address any unqualified claims.  This therefore remains an area that is under increased scrutiny particularly in the food and fast moving consumer goods sector.

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Every piece of content we create is correct on the date it’s published but please don’t rely on it as legal advice. If you’d like to speak to us about your own legal requirements, please contact one of our expert lawyers.

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