Advertising agencies sell a bundle that varies enormously from firm to firm, which is why buyers so often compare quotes that are not comparable. One agency's proposal is strategy and creative with media bought elsewhere; another's is media buying with creative attached; a third is a production shop with a strategist on the cover. Before comparing prices, it is worth being precise about which of those you need. This page sets out the types, the fee models and their incentives, the disclosure rules that now sit over most campaigns, and the evidence to collect before you appoint anyone.
The types, and which one your problem needs
Full-service agencies cover strategy, creative and media, and suit buyers who need one accountable partner across channels. Creative agencies and studios sell ideas and production, and are the right call when the strategy is settled and the work is to make something good. Media agencies plan and buy inventory, and their value is in negotiation, planning and measurement rather than in the advert itself. Digital performance shops run acquisition channels and optimise to a cost per action. Public relations and communications firms earn coverage rather than buy it. Specialists sit inside all of these by sector or channel. The mistake is buying a full-service relationship for a single-channel problem, which means paying coordination overhead for coordination you do not need, or buying a production shop when the real problem is that nobody has decided who the customer is.
Fee models and the incentives they create
There are four common structures. A monthly retainer buys a defined scope and predictable access, and its risk is scope drift in both directions. Project fees suit discrete work and price poorly for open-ended optimisation. A percentage of media spend is still common in media buying and creates the obvious incentive: the agency earns more when you spend more, whether or not spending more works. Performance-based pricing aligns interests but requires attribution both parties trust, which is harder than it sounds and tends to make the agency conservative about experiments. None is wrong, but each one shapes behaviour, so the question worth asking a candidate is what their model would push them to recommend that you might not need. The answer, and their willingness to give it, is informative.
Disclosure rules now sit over most campaigns
Modern campaigns lean on creators, reviews and affiliate arrangements, all of which carry disclosure duties that fall on the advertiser as well as the publisher. Endorsement guidance requires that a material connection between an endorser and an advertiser be disclosed clearly and conspicuously, and a material connection includes payment, free products, discounts, family ties and employment. Advertising disclosure guidance for digital media adds that qualifying information must be near the claim, hard to miss, and effective on the device the consumer is actually using, and that a disclosure cannot fix an inherently misleading claim. In practice, briefs to creators should specify disclosure in the content itself, contracts should require it, and someone on your side should be spot-checking that it appears. Ask a candidate agency to show you the disclosure clause in their standard creator contract; the ones who take it seriously produce it immediately.
The evidence to gather before appointing
Start with what is public: published pricing, stated minimums, named sectors and live examples of work. Then ask for three things a pitch does not naturally provide. First, the team who will actually run the account, by name, and how much of their time you get, since pitch teams and delivery teams frequently differ. Second, a reference from a client of similar size and sector, ideally one that has left, because departing clients describe the weaknesses accurately. Third, the measurement plan, written before the campaign, including the baseline, what would count as failure and when you would both agree to stop. Add the commercial terms: ownership of accounts, data and creative assets, notice period and what happens to work in progress. An agency comfortable with all of this is one that expects to be judged, which is the trait most correlated with being worth the fee.
Questions people ask about advertising agencies
What is the difference between an advertising agency and a marketing agency?
In practice the labels overlap. Advertising agencies traditionally emphasise creative and paid media; marketing agencies often include search, content, email and lifecycle work. Judge on the actual scope in the proposal rather than the name.
Is a percentage of media spend a fair fee model?
It is common and workable when the percentage and the services it covers are explicit. Be aware it rewards larger budgets, so ask for the equivalent flat fee too and compare both at your current and doubled spend.
Who owns the creative work and the ad accounts?
Whatever the contract says, so make it say your business. Ownership of ad accounts, tracking data, audiences and final creative assets should transfer or belong to you, with the agency granted access as a user.
How should influencer and creator campaigns be disclosed?
Clearly, in the content itself, whenever there is a material connection such as payment, free product or employment. Endorsement guidance places responsibility on the advertiser as well as the creator, so contract for it and spot-check compliance.