How ASA and CMA rules apply to keyword claims in UK advertising content

What to take away

How the ASA CAP codes treat keyword-driven claims

The Advertising Standards Authority writes and enforces the CAP advertising codes, which cover non-broadcast ads including paid search, display, landing pages and social posts. The rules apply to the whole ad, and a headline keyword is read as a claim, not decoration.

That matters because a keyword like "cheapest business broadband" is a promise about price leadership across a market. If the page cannot show that, the claim fails. The codes require claims to be honest, decent and truthful, and to hold evidence before publication rather than after a complaint.

The CAP code also expects qualifications to be clear. A tiny asterisk at the foot of a landing page does not rescue a bold claim in a title tag or H1. If the qualifier changes the meaning, it belongs next to the claim.

Keyword targeting often pushes writers towards the shortest, strongest phrase available. Search volume rewards absolutes, and the CAP code punishes them. That tension is the practical heart of ASA CMA keyword claims work.

Before you build ad groups around a claim, it is worth checking the keyword research advertising rules that apply to the terms you plan to bid on.

Where the CAP code bites hardest

Three areas attract complaints: price and availability, comparative superiority, and anything that sounds like a promise of an outcome. Each is a factual claim, so each needs a factual basis.

Availability claims are easy to get wrong. "In stock" on a page that ships in three weeks is misleading even if the words are technically about a warehouse.

What the CMA expects from comparative and price claims

The Competition and Markets Authority enforces consumer protection law alongside the ASA, and its guidance on misleading claims covers the same advertising content from a different angle. Where the ASA can require an ad to be withdrawn, the CMA can act on the underlying commercial practice.

The Consumer Protection from Unfair Trading Regulations 2008 prohibit misleading actions and omissions in commercial practices. A landing page that hides a mandatory fee, or a keyword that implies an endorsement the business does not have, can breach them. These are criminal offences, not just code breaches.

The Digital Markets, Competition and Consumers Act 2024 strengthens that regime, giving the CMA the power to decide that a practice is unfair and to impose penalties directly rather than going to court first. For content teams, the practical effect is that weak substantiation now carries financial risk, not only reputational risk.

Comparative claims need a clear basis. "Better than [named competitor]" requires a defined measure, a fair comparison and evidence that a reasonable reader would accept. Price comparisons must use like-for-like products and current prices, and should state the comparison date or period.

UK regulations shape keyword research here more than most teams expect, because the terms you choose determine which claim you are making.

The substantiation file

Keep a short evidence note for every claim in a keyword set: what the claim says, what proves it, who owns the proof and when it expires. An evidence file is what turns a risky claim into a defensible one.

Keyword claims that breach the rules, with examples

Rulings show the pattern clearly. The ASA publishes its decisions, and the rulings archive is a free record of wording that failed.

A recurring example is the broadband and mobile sector, where price and speed claims are checked constantly. Ads that led with a headline price and buried a mid-contract rise, or that claimed a speed only a minority of customers received, have been upheld against. The wording was not a lie in isolation; it misled in context.

Another common category is environmental wording. Broad terms like "eco-friendly" or "carbon neutral" used without a defined, verifiable basis have been upheld against because readers take them to mean a measurable reduction, not an offset purchase.

Health and beauty claims follow the same logic. "Clinically proven" without a cited trial, or a before-and-after image that implies a typical result, will be treated as misleading.

Wording that tends to fail

Fixing wording: from absolute claims to substantiated claims

Most fixes are swaps, not rewrites. Take the absolute claim out of the keyword and put the proof in the body copy.

A worked example. "Cheapest CRM in the UK" becomes "Our Starter plan costs less per seat than the published list prices of five named UK CRM providers, checked in September 2026". The second version is longer, but it is true, checkable and still ranks for price-led queries.

"Award-winning" becomes "Winner of the [named award], [category], [year]". "Cures back pain" becomes "Designed to support mobility for people with mild lower back discomfort". Each keeps the search intent while removing the exposure.

If your team writes down how claims are chosen and reviewed, a simple disclosure policy keeps that decision auditable.

Qualifiers that work

Qualifiers should narrow the claim, not hide it. "In our 2026 survey of 500 UK customers" is a qualifier. "Terms apply" is a disclaimer. The first informs; the second deflects.

Sector sensitivities: health, finance and children

Some sectors carry extra rules on top of the CAP code, and keyword choice matters more there because the terms themselves imply regulated outcomes.

Health and beauty claims must not suggest a medicinal effect for a cosmetic, and must not discourage essential treatment. Keywords like "treats" or "cures" are high risk; "supports" and "helps maintain" are safer where the evidence is weaker.

Financial promotions must be fair, clear and not misleading, and credit claims need representative examples. A keyword promising "instant approval" or "no credit check" invites scrutiny unless the terms genuinely match.

Children's advertising adds rules on targeting and on claims that exploit inexperience. A keyword aimed at under-18s that implies social pressure to buy will be judged harshly.

Across all three, the rules and ethics to follow are the same in shape: say what you can prove, and prove it before you publish.

Sector quick reference

Using ASA Copy Advice and rulings before you publish

The ASA runs a free, confidential Copy Advice service for non-broadcast ads, which gives a view on whether proposed wording is likely to breach the codes. It is not a pre-clearance assurance, but it is the cheapest risk reduction available to a UK content team.

Use it for new claim types, not for every page. Send the headline claim, the supporting evidence and the context in which it appears. Turnaround is typically a few working days, so build it into campaign planning rather than the final proofread.

Rulings are the other free resource. Search the archive for your sector and read the reasoning, not just the outcome. The ASA explains why wording failed, which is more useful than the verdict.

A practical review routine

An ASA and CMA keyword claims checklist

Run this before a landing page or ad group goes live. It takes an hour and prevents most complaints.

The CAP advertising codes govern the wording, and the Advertising codes are the primary reference for what an ad may say. The Consumer Protection from Unfair Trading Regulations 2008 set the legal floor beneath them.

The Digital Markets, Competition and Consumers Act 2024 gives the CMA stronger tools to act on misleading practices without going to court. The Copy Advice service is where you test wording before it becomes a complaint.

Common questions