A guide to the CAP Code and CMA for UK copywriting claims

Does the CAP Code cover every business message?

No. The CAP Code governs non-broadcast advertising, sales promotions and direct marketing in paid space. Editorial material is usually outside its scope unless paid placement or promotion makes it a marketing communication.

The practical test is who paid for the space or reach. If a client paid, the message is likely to count as marketing communication. The CAP advertising rules cover paid print, posters, direct mail, email marketing and social posts, alongside other non-broadcast advertising.

The Committee of Advertising Practice writes the Code, while the ASA enforces it independently of the industry. Ads should be legal, decent, honest and truthful, and prepared responsibly towards consumers and society. More specific provisions address price claims, comparisons, health, children and testimonials.

These rules apply in England, Scotland, Wales and Northern Ireland, with no separate Scottish advertising regulator. A Glasgow or Cardiff campaign is assessed under the same Code as one from London. Editorial copy on a company blog is treated differently unless paid placement or promotion brings it within scope.

What proof should exist before a claim appears?

Evidence must already exist when a claim is published, and it must support the meaning consumers are likely to take from the wording. Proof supplied later does not fix the timing problem.

Keep records that connect each statement to its supporting material, and make sure the evidence fits the claim rather than a weaker or narrower point. The ASA may ask the advertiser to produce that substantiation. Consumer research should reflect the actual claim and the audience's likely interpretation.

Rule 3.1 says an ad must not materially mislead or be likely to, and rule 3.7 requires documentary evidence for objective claims to be held before the ad runs. Rule 3.9 requires significant limitations and qualifications to be stated. Rules 3.17 and 3.18 govern price statements, which must not mislead by omission and must include non-optional charges.

A comparison needs a fair, verifiable basis and a clear account of what is being compared. A price comparison can mislead if it leaves out delivery charges, even where its displayed figures are accurate. Check the overall impression and the full basis of the comparison before approving the copy.

Comparisons with identifiable competitors have their own rules in Section 3. Testimonials and endorsements are covered by the rules from 3.45, which require documentary evidence that a testimonial is genuine and contact details for whoever gave it. Rule 2.1 requires ads to be obviously identifiable, which is why paid endorsements must be labelled.

Testimonials should be genuine, relevant and used with permission. An old review can mislead if the service has materially changed. Paid or incentivised recommendations also need clear disclosure: payment, a free product or another benefit may affect how an audience understands the endorsement.

A gifted stay, discounted service or affiliate link needs disclosure. Hiding #ad after a long string of hashtags may not make the commercial relationship obvious. Health, beauty and food claims need particular care; statements that a product cures, treats or prevents disease face a higher evidential standard.

Take an invented skincare page that claims it is clinically proven to reduce wrinkles by 40% in seven days, recommended by dermatologists, and as seen in Vogue. Check every phrase separately, then consider the combined impression against the supporting records before approving the layout or wording.

A more precise alternative could state that, in a 12-week study of 60 participants, 40% reported visibly smoother skin, followed by the qualification that individual results vary. That wording specifies the study period, participant number and reported outcome. Review the product page as a complete message, not as isolated statements.

Can both bodies scrutinise the same wording?

Yes. A misleading claim can raise an advertising concern and a consumer-law concern at the same time. False price comparisons, invented reviews and unsupported health claims may interest both the ASA and the CMA.

The ASA handles complaints and publishes rulings as a self-regulatory body funded by a levy on the advertising industry. The CMA investigates markets and enforces consumer law through court processes or its own penalty powers. Their approaches differ, but misleading wording can matter to both.

Other regulators may be relevant to particular sectors. The Financial Conduct Authority deals with financial promotions, the MHRA with health and medicines claims, and the Information Commissioner's Office with data-driven marketing. Copy involving personal data also needs to meet UK GDPR requirements alongside the CAP Code, so broader compliance rules may apply.

Does the CMA look beyond advertisements?

Yes. The CMA may examine the wider commercial relationship with consumers, including pricing, subscriptions, reviews, contract terms, environmental statements and online choice design, rather than focusing only on advertising wording.

The CMA overview describes its work to make markets function well for consumers, businesses and the economy. Its consumer protection remit is now the unfair commercial practices provisions in Part 4, Chapter 1 of the Digital Markets, Competition and Consumers Act 2024 (the DMCC Act), in force since 6 April 2025. They replaced the Consumer Protection from Unfair Trading Regulations 2008. The Business Protection from Misleading Marketing Regulations 2008 still protect businesses from misleading marketing.

Environmental statements can cause concern if they are unclear, incomplete, untruthful or unsupported across a product's life cycle. The CMA's Green Claims Code is the practical reference, and Section 11 of the CAP Code covers environmental claims. Calling something eco-friendly or carbon neutral without evidence can therefore raise a consumer protection issue as well as an advertising question. Choice design can also matter when it steers a decision instead of informing it.

Examples include drip pricing, scarcity messages, confirm-shaming and countdowns that reset on refresh. The CMA may begin examining an issue itself or after a complaint from a consumer body, competitor or trading standards service. It does not need a single individual complainant to start work, so check UK regulations before publication.

Who may face action when a claim is wrong?

The ASA acts against the advertiser, not the writer. The CMA may act against businesses involved in a misleading practice, while a client may pursue a copywriter under their contract if supplied wording proves false.

Sanctions beyond a ruling include:

The ASA can publish a ruling naming the advertiser and describing the advertisement, and may require the copy to be withdrawn or amended. Continued non-compliance can bring further measures, including restrictions on buying advertising space and pre-vetting of future advertising. Pre-vetting is generally used for repeat offenders and lasts for a set period.

The CMA has different options, including accepting undertakings, seeking a court enforcement order or imposing direct fines under the DMCC Act. Since April 2025 it can fine a business up to 10% of global turnover for breaching the consumer protection provisions, without going to court.

Consumers may sue over losses caused by misleading copy, while competitors may bring claims involving malicious falsehood or misleading marketing. Platforms can also remove advertisements under their own policies, potentially costing a campaign its budget. Set out approval responsibilities in commercial terms and consider the agency's reputation. A freelance copywriter should retain a clear record of who supplied and checked each claim.

Can someone assess a draft before launch?

Yes. The ASA offers confidential, free Copy Advice to advertisers, agencies and media owners. It can flag likely Code problems, but it is not binding pre-clearance and cannot guarantee that a later complaint will be rejected.

Copy Advice relates to the draft submitted. If the published version changes or new evidence appears, earlier advice may no longer settle the issue. AdviceOnline offers a searchable library of Code provisions, help notes and past ASA rulings, which can help teams understand how similar wording has been treated.

For each campaign, list the claims, identify their supporting material, check that the wording matches it, and record the reviewer and version. Seek advice before release if uncertainty remains, then retain the approved copy and the evidence behind it. A named reviewer and version history make the checks easier to trace.

Where do readers report a claim?

To challenge an ad, make a complaint to the ASA through the complaint form on its website. The CMA does not resolve individual consumer complaints. Consumers should use Citizens Advice's consumer service, and trading standards services can act on local breaches. Copywriters can use AdviceOnline and Copy Advice before publication instead.

What should I do first?

Start by identifying the claim, its supporting evidence and the rules that apply to the channel. Then check the overall impression, consider the wider customer journey and keep a record of the review.