Ad agency pricing: how agencies charge, and which model fits you
Ad management is priced three different ways, and each one pushes the agency to behave differently. How management fees are set and where the conflict of interest sits.
Comparing ad agency prices is hard because agencies price the same work on three different logics. The gap between two proposals is usually not “one is expensive, one is cheap” — they are selling different things.
More importantly: the model you pick determines how the agency behaves inside your account. Each one carries its own conflict of interest, and you should choose knowing what it is.
A note on terms: what follows is the management fee — what you pay the agency. The media budget paid to Google is a separate line, and we covered how to size it in the Google Ads budget piece; to work out your own number, use the budget calculator.
Model 1 — Percentage of ad spend
The most common model. The agency takes a percentage of your monthly media spend, typically 10-20%, with the rate falling as spend grows.
Where it works: Fair when spend is large and workload genuinely scales with it. Simple to set up, predictable to invoice.
The conflict: The agency earns more when you spend more. An agency recommending that you cut spend is recommending a cut to its own revenue — so mostly it doesn’t. Yet one of the most valuable moves in account management is switching off a campaign that isn’t working.
How to balance it: Write a cost per acquisition target into the contract, not a spend target. Not “we will spend $8k a month” but “cost per customer stays under $180.”
Model 2 — Flat monthly retainer
Scope is defined, the fee is fixed. Whatever you spend, the invoice is the same.
Where it works: Usually the cheapest model at small and mid spend levels. Your costs are predictable, and the agency has no incentive to inflate your media budget.
The conflict: It inverts — the agency is more profitable the less time it puts into your account. Retainer accounts get intense attention for two months and then go on autopilot. If the agency’s roster has bigger accounts than yours, attention drifts there.
How to balance it: Write the scope concretely. How many campaign revisions a month, how many new ad variants, how many reporting calls? The phrase “account management” commits to nothing on its own.
Model 3 — Performance-based
A low base fee plus a commission per sale or conversion.
Where it works: In theory the fairest model. In practice it only works if your measurement is airtight. The logic behind it is the logic of performance marketing: payment is tied to outcomes, not to spend.
The conflict: This one is the subtlest. If commission is paid per “conversion,” the agency drifts toward channels that manufacture cheap conversions — brand search and remarketing. Those are customers who were coming to you anyway, now booked to the agency’s ledger. Real growth comes from the expensive, difficult work of new demand.
How to balance it: Tie commission to closed sales, not form fills, and exclude brand search from the commission calculation. That requires a setup that writes CRM outcomes back to the ad platform; the technical side is in the GA4 measurement guide.
What proposals leave out
The same questions apply to all three models:
- Is there a setup fee? Account structure, conversion tracking and landing page work are usually priced separately.
- Whose card pays the media? If it runs through the agency’s card, your access to raw spend data is limited and the account history doesn’t stay with you when you leave.
- Are landing pages and creative included? In most proposals they aren’t. Good ads plus a bad page equals a bad result.
- Minimum term and notice period. An agency demanding a 12-month commitment may know it can’t show results in three.
- Reporting frequency and what gets reported. Clicks and impressions say nothing; cost per acquisition and closed revenue do.
The clause that matters most: whose name is on the accounts
This deserves its own heading, because it is the only thing you keep the day you change agencies.
The Google Ads account, Meta Business Manager, Analytics property and Search Console must be created in your name, with the agency invited as a manager. When it’s the other way round — a sub-account under the agency’s own umbrella — leaving costs you:
- All historical performance data and accumulated learning
- Your remarketing audiences
- Conversion history, meaning everything the algorithm learned
None of it transfers. Starting over sets you back three to six months. One sentence to ask before signing: “Will the accounts be opened in my name?”
What to expect, roughly
Figures can mislead because scope differs in every proposal, but as a frame:
- Single channel, modest spend, basic management → a flat retainer is usually cheapest.
- Multi-channel account with high monthly spend → percentage of spend, in the 10-15% band.
- Measurement in place, clear sales cycle → base fee plus closed-sale commission.
The number to judge on isn’t the agency’s price. It is cost per acquisition including the management fee. An agency charging $1,500 a month that cuts cost per customer by $90 is cheaper than one charging $500.
We collected the full set of questions to ask in how to choose a Google Ads agency. If you’d like a look at where your current account stands, our digital marketing practice starts with an account review.
