How to review a marketing agency's advertising rules

What to take away

Check that an agency can identify whether a campaign follows the CAP Code or the BCAP Code, and explain the ASA's role.
Ask how it checks claims against the law on misleading consumer and business advertising.
For email, SMS and automated calls, ask how it checks the Privacy and Electronic Communications Regulations 2003 (PECR).
Request evidence of claim substantiation, client approval and clear labels for paid influencer content.
Ask how the agency records decisions; keep a dated approval trail for each claim, image and testimonial.
If a client is involved in a merger investigation, ask how the agency manages conflicts and confidential information.

Start with the CAP Code

The Committee of Advertising Practice writes the CAP Code for non-broadcast advertising and the Broadcast Committee of Advertising Practice writes the BCAP Code for broadcast advertising. Together, they form the UK Advertising Codes, which the Advertising Standards Authority administers through self-regulation and co-regulation. The overview of advertising regulation in the UK explains that split for agencies.

For broadcast advertising, the ASA administers the BCAP Code under co-regulatory arrangements with Ofcom, under the Communications Act 2003. Ofcom's Broadcasting Code covers broadcast standards; the BCAP Code sets the advertising rules. When reviewing an agency, check that it can identify the right code for each channel.

Self-regulatory codes sit alongside statutory rules. For consumer-facing unfair commercial practices, Part 4 of the Digital Markets, Competition and Consumers Act 2024 is the current framework; it replaced the Consumer Protection from Unfair Trading Regulations 2008 from 6 April 2025. The Business Protection from Misleading Marketing Regulations 2008 address misleading business-to-business advertising, and the CMA and Trading Standards enforce relevant consumer-protection laws.

Build a pre-flight checklist

Use these six checks to review an agency's process for a UK campaign:

Check that it identifies the channel and the applicable CAP Code or BCAP Code.
Ask how it substantiates objective claims before publication.
Check that it reviews claims for misleading content under the relevant consumer or business advertising law.
For email, SMS and automated calls, ask how it checks PECR requirements, including consent where required.
Confirm that it obtains client approval and records who approved each claim and when.
Ask how it checks influencer advertising labels and keeps the supporting brief and evidence.

Campaign pre-flight checklist

Client approved final copy in writing
Objective claims backed by documented evidence
Testimonials verified as genuine and current
Images and music licensed per channel
Log approval date, name, version number
Re-check if price or terms change

Who signs off the claim?

The client should approve its claims and provide supporting evidence, but approval does not necessarily remove the agency's own exposure. When reviewing an agency, ask for its process for checking evidence and recording decisions. If a client refuses to provide evidence, put the campaign on hold and record the decision. The ASA can rule against the brand, and the agency's reputation may suffer alongside it.

What about influencer content?

Label paid influencer posts clearly as ads. The CAP Code treats a commercial relationship as advertising, even when the creator writes the script. Keep the brief and the label instruction in the file.

PECR and electronic marketing

Email, SMS and automated calls are covered by the Privacy and Electronic Communications (EC Directive) Regulations 2003 (PECR). The Information Commissioner's Office (ICO) enforces PECR and its guidance explains consent, the soft opt-in and limited exceptions. Ask an agency how it checks the rules before a list is used; the ICO can investigate and issue monetary penalty notices for serious breaches.

For wider compliance, see UK rules and compliance guide for 2027, mapping each obligation to the document proving it.

Mergers and client conflicts

The Enterprise Act 2002 provides the statutory basis for UK merger control. The CMA's guidance, Mergers: Guidance on the CMA's jurisdiction and procedure (CMA2), explains its jurisdiction and process; the CMA mergers guidance collection covers information requests and confidentiality expectations. When reviewing an agency for work involving competing bidders, ask how it checks conflicts and protects confidential information. The client's legal team can advise whether information or a pitch needs to be disclosed.

Contracts and disclosure

Advertising rules sit in the commercial contract. The engagement letter should name who approves claims, who owns the creative, and what happens if a regulator investigates. For England-specific drafting points, see marketing agencies commercial contracts in England, which covers indemnities and approval clauses in plain terms.

Without those clauses, an agency may carry the cost of a reprint or a takedown.

Common questions

Do the same advertising rules apply in Scotland, Wales and Northern Ireland?

The CAP Code and PECR apply across the UK, and the ASA administers the UK Advertising Codes UK-wide. Broadcast advertising follows the BCAP Code, with Ofcom involved in co-regulation. An agency should check the applicable code and law for each campaign and channel.

Can an agency be fined for a client's misleading ad?

The ASA itself does not fine. It publishes rulings and can refer persistent non-compliance to Trading Standards or Ofcom, which hold statutory powers. The ICO also has enforcement powers under PECR. The advertiser usually carries primary responsibility, but an agency's liability depends on its role and the applicable law.

How long should approval records be kept?

Keep campaign approvals for the length of the campaign plus a margin, and longer if the client's sector rules require it. The record should show what was approved, by whom and when.

Does a merger investigation stop an agency from pitching?

No, but an investigation can affect how information is shared between competing clients. Ask the agency how it applies the CMA's Mergers: Guidance on the CMA's jurisdiction and procedure (CMA2) and manages conflicts; take legal advice before the pitch proceeds.