A map of who regulates what in UK advertising
The ASA and its CAP Code cover most ad content, Ofcom oversees broadcast, and the ICO governs how you use customer data for targeting. This map sets out which body and which rule applies to your channel, so you know what to check before a campaign goes live.
Check a test's significance with the A/B Test Significance Calculator Read our guide to advertising on a small budget in the UKOne rulebook, several regulators
UK advertising is not policed by one regulator. The Advertising Standards Authority (ASA) enforces the CAP Code, the rulebook covering most non-broadcast advertising: print, posters, online display, and paid social. Broadcast advertising on TV and radio is judged against the same CAP Code principles, but Ofcom sits behind it as the body that licenses broadcasters and sets the rules for how ads are scheduled around programmes.
Where an ad campaign uses personal data, a second layer applies. The Information Commissioner's Office (ICO) governs how that data can be collected and used, so a retargeting campaign has to satisfy both the CAP Code's rules on honesty and the ICO's rules on consent at the same time. Pricing claims, subscription traps, and misleading discounts are a separate matter again, and fall to the Competition and Markets Authority (CMA), which polices consumer protection and competition law.
- ASA / CAP Code: truthfulness, decency, and the targeting of vulnerable audiences in ad content, broadcast and non-broadcast
- Ofcom: broadcaster licensing and the scheduling rules around broadcast ads
- ICO: data collection, consent, and use in targeted or retargeted advertising
- CMA: pricing claims, consumer protection, and competition law
Knowing which body applies matters in practice, because a complaint sent to the wrong regulator goes nowhere, and a business that assumes one clearance covers every rule can find a second regulator asking questions it did not expect. The CAP Code is updated periodically, so treat any rule referenced on this map as a starting point and check the current wording at asa.org.uk before relying on it. For a fuller walkthrough of what the ASA actually requires, see the guide to UK advertising rules.
UK advertising regulators, and what each one covers
Each body polices a different slice of an advertising campaign, and more than one can apply to the same ad if it runs across channels or collects data. Use the table to work out who to check with.
| Regulator | Covers | Typical concern |
|---|---|---|
| ASA, under the CAP CodeCovers most of what a small business actually places. Check asa.org.uk for the current CAP Code before relying on any summary of it. | Non-broadcast ads: print, posters, websites, paid social, influencer posts, email | Misleading claims, unclear pricing, ads not obviously labelled as ads |
| ASA, under the BCAP CodeSame regulator as the CAP Code, different rulebook because broadcast reaches a captive audience. | Broadcast ads on TV and radio | Scheduling restrictions around children's programming, health and financial claims |
| OfcomMost advertisers deal with the ASA day to day; Ofcom sits behind it as the statutory authority for broadcast. | Broadcast licensing, and the statutory backstop if a broadcaster disputes an ASA ruling | Sponsorship credits and programme sponsorship rules on TV and radio |
| ICORelevant the moment a campaign uses cookies, pixels, or a customer email list. | Data protection and direct marketing rules, including cookies and email consent | Tracking without proper consent, unsolicited marketing emails or texts |
| CMASteps in where a practice goes beyond the ad itself into how a sale is actually structured. | Wider consumer protection law: pricing practices, subscription traps, fake reviews | Drip pricing, hidden subscription terms, false scarcity claims |
This is general orientation, not legal advice, and regulatory codes are updated periodically. Verify current rules directly with the ASA, Ofcom, the ICO or the CMA before relying on any of it.
How a complaint becomes a ruling
UK advertising regulation is not a single body issuing licences before an ad runs. It works as a sequence: a code written in advance, then a complaint or a piece of monitoring that brings a live ad to the regulator's attention, and finally a ruling that clears the ad or requires it to change. The steps below follow that order, including where the process forks depending on the medium used and how the case is resolved.
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The codes are written first
Before any ad is made, the rules already exist. The Committee of Advertising Practice (CAP) writes the CAP Code for non-broadcast advertising, which covers print, posters, online ads, email and direct mail, and the BCAP Code for television and radio. The Advertising Standards Authority (ASA) does not write these codes; it administers and enforces them.
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Some ads are checked before they run
Whether an ad gets looked at before it airs depends entirely on where it's going to run.
BroadcastTV ads go through Clearcast and radio ads through Radiocentre's copy clearance service, both checking against the BCAP Code before a broadcaster will schedule them.
Non-broadcastOnline, print and poster ads have no compulsory pre-check. CAP's Copy Advice service is free and optional, and it offers a view on the Code, but it doesn't guarantee the ad will pass if challenged later.
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The ad runs
Once live, the ad is bound by the relevant code whether or not the advertiser sought advice beforehand. Pre-clearance reduces risk; it doesn't remove the ad from the ASA's reach once it's out in the world.
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Something brings it to the ASA's attention
A live ad reaches the regulator by one of two routes, and which route it takes affects how the case starts.
Complaint-ledA member of the public, a competitor or a campaign group flags the ad through the ASA's online complaints system.
ASA-initiatedThe ASA's own monitoring picks up the ad directly, without anyone lodging a complaint, and this is how it tracks recurring problem areas such as misleading environmental claims or gambling ads reaching under-18s.
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The ASA assesses it against the Code
Most cases don't end in a published ruling.
Resolved informallyThe advertiser withdraws or amends the ad once contacted, and the ASA closes the file without a formal published decision.
Formal investigationThe advertiser disputes the complaint, or the issue is serious enough to warrant one, and the case goes to a full investigation with a published ruling.
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The ruling is published and, where upheld, enforced
A ruling of not upheld ends the matter. A ruling of upheld means the ad must not appear again in its current form, and what happens next depends on the medium, because the ASA's own powers stop short of fines for most advertisers.
The CAP and BCAP Codes are revised from time to time, so treat any specific rule referenced here as a starting point, and check asa.org.uk directly before relying on it.
Broadcast breachOfcom holds the statutory backstop for broadcast advertising and can fine a broadcaster or, in serious or repeated cases, act against its licence.
Non-broadcast breachThe ASA can withdraw an advertiser's trading privileges, require its future ads to be vetted before they run, ask media owners to withhold space, or refer persistent offenders to Trading Standards or the CMA.
This sets out the general mechanism as it applies to most advertisers. Specific sectors, such as gambling, financial promotions and healthcare, carry additional rules and additional regulators alongside the ASA, and a case involving any of them may not follow this sequence exactly.
Compliance tells you what you can say. It doesn't tell you what to spend, or whether what you spent worked.
Once you've checked where a channel sits on the regulation map, the next questions are practical: how much to put behind it, and whether the result you're looking at is real or just noise. Both calculators work from whatever figures you put in, so a wrong input will point you the wrong way.