Keen on comparative advertising but vexed by verifiability? Read on for a straightforward guide to what it means, when it applies and how to make sure your ad complies.

What does ‘verifiable’ mean?

‘Verifiable’ simply means setting out the relevant information about a comparative claim in your ad or signposting how the information used to make that comparison can be checked by the target audience.

The CAP Code requires that comparisons with identifiable competitor products “must objectively compare one or more material, relevant, verifiable and representative feature of those products” (Rule 3.35).

When does this rule apply?

The verifiability requirement applies to all comparative ads. Comparative advertising here means advertising which in any way, either explicitly or by implication, identifies a competitor or a product offered by a competitor, so you don’t have to name a competitor for it to apply. If you claim to be the cheapest in the market, run the highest ranked website or just offer a price match scheme then the comparison needs to be verifiable.

How do I make sure my ad complies?

You need to provide the ad’s audience with enough information about the comparison to understand it. If the checking requires special knowledge most consumers are unlikely to have, readers should be able to get a knowledgeable and independent person or organisation to verify the comparison using that information.

If you have not included all the relevant information in the ad (such as where detailed testing information is included) then you should clearly signpost in the ad itself how it can be obtained. This could be done by stating “the claim can be verified at www.[website].co.uk/comparisons” or by inviting readers to write to a postal or email address.

The nature and amount of information you need to provide will depend on the comparison being made. If the comparison is straightforward (such as a price comparison between two products), you might only need to include brief information in the ad such as where and when the prices were checked. For more complex comparisons (such as a grocery ‘swap and save’ challenge including many products), you might need to include a signpost in the ad to more detailed information about the comparison, including both the results and methodology. For some claims, it might be sufficient to provide a detailed methodology only, if the results could be replicated using that information.

Verification information is not necessarily the same level of evidence that will be required by the ASA as substantiation for claims in an investigation - if in doubt consult CAP Copy Advice about how much information you should include.

Anything we should avoid?

The ASA has previously upheld complaints where:

For further guidance see the CAP AdviceOnline article on Comparisons: Verifiability.

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