The Advertising Standards Authority (ASA) is the UK’s independent regulator of advertising. It decides whether ads break the UK advertising codes, and it can require a business to change or withdraw an ad that misleads, causes harm or seriously offends.
How the ASA works
The ASA applies two rulebooks. The CAP Code covers non-broadcast marketing, from paid search and social ads to influencer posts and the claims a business makes on its own website. The BCAP Code covers TV and radio, under an arrangement with Ofcom. The ASA does not write either code; two industry committees do, and the ASA enforces them.
Anyone can complain to the ASA free of charge through its website: a member of the public, a competitor or a trade body. The ASA also looks for problems itself, including through automated monitoring of online ads. Simple cases are often settled informally, with the advertiser agreeing to amend the ad. When a case goes to a formal investigation, the ASA publishes a ruling on its website that names the business, shows the ad and says whether the complaint was upheld.
The ASA cannot fine anyone. Its sanctions are practical: asking media owners and platforms to refuse a business’s ads, getting paid search ads removed, running its own ads naming businesses that will not comply, and referring persistent offenders to Trading Standards, or to Ofcom for broadcast ads. Separately, the Competition and Markets Authority can now fine businesses directly for breaking consumer protection law, so a misleading claim can carry more than one kind of risk.
Why it matters
Most ASA rulings involve ordinary businesses rather than household names. A clinic claiming a treatment works for everyone, a broadband reseller whose headline price leaves out a fee, or a trades firm calling itself the cheapest in London without proof can all end up with a published ruling that appears in search results for their own name.
The ASA’s remit also reaches into SEO and content work. The claims on your service pages, pricing page and testimonials are marketing, so they are covered. Organic search listings themselves are not, but the page a listing points to can be.
It is easy to confuse the ASA with platform rules. Meta’s advertising standards and Google’s ad policies decide whether a platform will run your ad; the ASA decides whether the ad is acceptable under the UK codes. An ad can pass one and fail the other.
Common mistakes
- Publishing a claim first and looking for evidence after a complaint arrives. The substantiation has to exist before the ad runs.
- Assuming a small budget keeps you under the radar. Competitors complain, and complaining costs them nothing.
- Treating influencer posts as the influencer’s problem. The brand shares responsibility for making sure paid posts carry clear ad labelling.
- Copying a competitor’s wording because they appear to get away with it.
- Ignoring an enquiry from the ASA. Not responding usually leads to a ruling against you.
How to act on it
Review the claims you make most often: price, best or number one, speed, results, free, and anything about health or the environment. For each, write down the evidence you hold and where it is kept. Remove or soften anything you cannot back up today.
Search the ASA’s published rulings for your sector before launching a new campaign; they show how the codes are applied to businesses like yours. For a new or unusual claim, the Committee of Advertising Practice offers a free advice service that will look at copy before it goes live. When I plan campaigns as part of my digital marketing strategy and consulting work, the main claims are checked against the codes before any ad is built.