When owners shop for someone to run their ads, they compare agency fees the way they compare quotes for a new roof. Who is cheaper, who includes more, who has the shorter contract. That is a reasonable way to buy a roof. It is an incomplete way to buy marketing, because an agency fee is not only a price. It is also a set of instructions.
Every way of paying an agency rewards the agency for something. A percentage of your ad spend rewards them when your budget goes up. A flat retainer rewards them for keeping the work efficient. A price per lead rewards them for producing more of whatever counts as a lead. None of those is evil, and good people work under all of them. But the person running your account is a person running a business, and over time the work drifts toward whatever the fee pays for.
So the useful question is not just "how much?" It is "what does this fee pay my agency to do, and is that the same thing I need done?" This piece walks through the common PPC management pricing models, what each one quietly rewards, which kind of business each one fits, and the questions that make any agency explain its fee in plain English.
Every Agency Fee Pays for Something. Most Owners Never Ask What.
Advertising agencies started out being paid by commission. The agency placed your ads in newspapers and magazines, and the publisher let the agency keep a cut of the media bill, traditionally 15%. You never wrote the agency a check for its time. It was paid out of the money you spent on ads, so the more you spent, the more it earned.
Most of the industry has moved on. The ANA, the trade association for large US advertisers, has surveyed its members about how they pay agencies since 1985. In its 2022 study, only 7% of advertisers still paid their agencies by commission overall, down from 70% in the first survey. Fees now make up 82% of arrangements.
Media buying is where the old habit survived. The same study found 19% of advertisers still paying commission for media planning and buying, nearly three times the overall rate. And in the small-business corner of the market, where the media is Google Ads and Meta, a pricing guide written for agency owners calls 10% to 20% of ad spend "the industry norm."
That is the starting point for most owners: a fee tied to the size of the budget, inherited from a time when an agency bought newspaper pages. It is worth understanding exactly what it pays for before you sign one.
A Percent-of-Spend Fee Gives Your Agency a Raise Every Time You Spend More
Here is the arithmetic, with round numbers. Say an agency charges 15% of what you spend on ads. At $5,000 a month in ad spend, the fee is $750. Raise the budget to $10,000 and the fee becomes $1,500.
Now ask what changed in the work. Same account. Same campaigns, mostly. Maybe a few more keywords and a little more reporting. The agency's revenue from you doubled, and its effort did not come close to doubling. That is not a scandal. It is simply what the contract says.
The problem sits in a fact about advertising that every honest operator knows: the next dollar is usually the worst dollar. In a Google Ads account, your first dollars buy the searches most likely to turn into customers. As the budget grows, the platform reaches further out, to broader searches, pricier clicks and people less likely to buy. Your cost per customer rises even when nothing is wrong. We walked through how to see this in your own numbers in Google Ads Stops Growing Before Your Budget Does.
Under a percentage fee, that worst dollar pays the agency exactly as well as the best dollar did. So when your agency recommends a bigger budget, the recommendation may be right, and it may also be a raise. You cannot tell which from the recommendation alone. You can only tell from what the extra money bought.
The agencies' own trade advice does not hide this. The same guide that calls 10% to 20% the norm lists the model's main drawback as one that "focuses on growing the investment which doesn't place the client's interests first," and puts it bluntly: "When you charge based on ad spend, you're essentially adding a markup to every lead generated."
Two details are worth knowing when you read one of these contracts:
- The floor. Many percentage fees come with a minimum, written as "15% of spend or a set monthly amount, whichever is higher." One large agency's published pricing reads exactly like that. On a small budget, you are really paying a flat fee. The percentage only starts working once your spend grows past the point where it beats the floor.
- The sliding rate. Some agencies lower the percentage as spend grows, for example 15% up to one level and 12% above it. That softens the raise. It does not remove it.
None of this makes percent of spend wrong for every business. It fits reasonably well when spend and profit genuinely rise together. That usually means an online store with reliable profit tracking that is scaling a product line it knows is profitable, where more spend really does mean more work for the PPC agency and more margin for you. The fit gets worse the further the extra budget sits from extra profit.
A Flat Retainer Pays for Time, and Most Retainers Never Say How Many Hours
A flat monthly retainer cuts the link between your budget and the agency's pay. The agency earns the same whether you spend $4,000 or $14,000, so it has no reason to talk you into spending more. For a lot of small businesses, that alone makes it the safer model.
But every fee creates a pull, and a flat fee pulls the other way. If the agency's income from you is fixed, its profit rises when your account takes less of its time. Advice written for agency owners is candid about this. One agency owner, in a video made for other agency owners, names three ways to grow an agency: win more clients, lose fewer, or raise the average retainer. She calls the retainer the easiest lever, the number "you can raise without doing any more work."
From the owner's side of the table, that is the whole issue in one sentence. A retainer that rises without more work, or holds steady while the work shrinks, has stopped paying for your account and started paying for the agency's margin.
A growth consultant describes a related pattern in businesses that hire an agency before they have a plan of their own. The agency fills the gap with deliverables and "vanity metrics," and, as he puts it, "they're going to make it look good for their business. It's not necessarily good for yours." A flat fee makes this easier to fall into, because the reports can keep arriving long after the thinking has stopped.
The fix is simple and almost nobody asks for it. Get the shape of the time in writing:
- Roughly how many hours a month land on your account, and who spends them.
- What is in scope, such as new campaigns, landing page reviews and conversion tracking, and what gets billed separately.
- What happens when the work outgrows the fee, so neither side quietly absorbs it.
An agency doesn't need to track time to the minute. But it should be able to describe what your monthly fee buys in terms you could check.
One Extra Dollar of Ad Spend Can Push Your Agency Fee Up a Whole Band
Some agencies split the difference: a flat fee, set by which band your ad spend falls in. Here is an example agency, with made-up numbers:
- Under $8,000 a month in ad spend: $800 a month
- $8,000 to $14,999: $1,200 a month
- $15,000 and up: $1,800 a month
Inside a band, this behaves like a flat retainer. Going from $8,000 to $14,000 in spend costs you nothing extra in fees, which a 15% agency would have billed at $900 more. The pull toward a bigger budget is much weaker than with a straight percentage.
The pull isn't gone, though. It moves to the edges between bands. In the example above, $7,999 of spend costs $800 in fees and $8,000 costs $1,200. One dollar of budget, $400 of fee. If your spend sits just under a line, it's worth knowing that line exists before anyone suggests a "small" increase.
Two things decide whether a band structure is fair to you:
- What moves you up a band. A tier set by one month's spend means a holiday push or a one-time promotion can bump your fee for that month. A tier set by an average of the last few months means a single busy month doesn't count. Ask which one your contract uses.
- What the next band buys. If the higher tier comes with more hours, more channels or more testing, the jump pays for something you can see. If it comes with nothing new, it's a percentage fee in disguise.
Pay Per Lead Pays for Leads, Not Customers
Paying a set price per lead sounds like the model that finally lines everyone up. You only pay when something happens. In practice, it lines the agency up with exactly one thing, the word "lead," and the whole arrangement rests on how that word is defined.
Say you pay $60 per lead and receive 40 in a month. That's $2,400. If 15 of those people never answer the phone and 10 wanted a service you don't offer, you paid $1,500 for 25 dead ends. The agency was paid for every one, because each was a lead by the contract's definition. Under this model, the agency's best month is the one with the most leads, whether or not your best month was the one with the most customers.
That doesn't make pay per lead a bad deal. It makes the definition the most important line in the contract. Before you sign, get clear on:
- What counts. A form fill, a phone call over a set length, a booked appointment? The further down that list, the more the agency's pay depends on real buyers.
- What doesn't count, and how you dispute it. Wrong numbers, duplicates, people outside your service area and requests for services you don't sell should all be excluded, with a way to flag them.
- Whether the lead is yours alone. Some lead sellers send the same person to several businesses. A shared lead is worth far less than an exclusive one.
- Whose ad account it is. Many pay-per-lead providers run the ads in their own account and sell you the output. When you leave, the account, the history and the data stay with them. We covered why that matters in Your Ad Account Is Not Yours.
It helps to compare this with Google's own pay-per-lead product. In Local Services Ads, you pay Google by the lead, and Google offers a process to get credit back for leads that don't fit your business. That is the standard to hold a third party to. If an agency charges by the lead, it should have a written answer to "what happens when the lead is junk?"
A Performance Bonus Is Only as Honest as the Number It Pays On
The last common model adds a bonus on top of a base fee when results clear a target. It sounds like the fairest deal of all. Big advertisers have been trying it for years, and they've grown less sure of it. In the ANA's surveys, the share of advertisers using performance incentives fell from 61% in 2013 to 48% in 2016 and 41% in 2022. Most respondents said they didn't know whether the incentives were improving their agency's performance.
The trouble is that a bonus turns one number into the agency's job. Pay on cost per lead, and you'll get cheaper leads, which are often worse leads. Pay on the conversion count Google Ads reports, and you're paying on a number the platform measures for itself. As we explained in You Will Never Know Exactly Which Ad Made the Sale, every platform claims credit for what it saw, not for what it caused. A bonus tied to the wrong number gets the agency to chase that number, and it will.
Small accounts have a second problem: noise. If you get 30 leads a month, a good month and a bad month can be the same work with different luck. A bonus that swings on that noise pays for luck, in both directions.
If you do pay for performance, tie it to a number from your own books, like booked jobs, closed revenue or new customers, measured over a quarter rather than a month. Agree on how it's counted before the money moves.
A Roofer With Steady Leads Shouldn't Pay the Same Kind of Fee as a Store Trying to Double Its Sales
There is no single best fee. There's the fee that pays your agency for the job you actually need done next. A few common situations:
- A local service business with a steady budget, like a roofer, a dentist or a law office spending about the same amount every month. You need careful, consistent management, not a growing budget. A flat retainer or a spend-band fee fits best. Watch the hours and scope, and make sure the fee stays tied to the work.
- An online store scaling something it knows is profitable. Spend and profit really do rise together here, so a percentage fee can be a fair fit, ideally with a sliding rate or a cap. Watch what each budget increase bought in profit, not in revenue.
- A business testing a new channel. The job is learning, not scale. A flat fee for a set test period, with a written definition of what success looks like, fits better than anything tied to spend. Watch for a test that keeps getting extended because it pays.
- A business that just wants booked appointments. Pay per lead can work if the definition is strict and the account is yours. Watch the gap between leads delivered and customers won.
Whichever you choose, know what a lead or a customer is allowed to cost you before you judge any fee. The fee is only expensive or cheap relative to what the work brings back, and that ceiling comes from your margin and close rate, not from the agency. We showed how to work it out in Your First Ad Budget Isn't an Investment. It's Tuition.
An Agency That Can't Say What Raises Its Fee Is Selling You a Mystery
You don't need to understand bidding strategies to evaluate a fee. You need five answers, and any agency worth hiring can give them on one call:
- What makes my fee go up? Name every trigger: spend, channels, hours, results. If the answer is vague, the fee is.
- If I doubled my budget tomorrow, what would happen to your fee, and what would you do differently? You want to hear about more work. If you only hear about more money, that tells you what the fee pays for.
- What did the last budget increase buy? Not in clicks. In leads, jobs or sales, compared with the month before.
- Roughly how many hours a month go into my account, and whose are they? A range is fine. "It depends" with no number isn't.
- If we part ways, what leaves with me? The ad accounts, the data, the conversion tracking. It should all be yours.
There's a sixth check you can make without asking anyone. Google requires any third party that manages Google Ads for you to tell you about its management fee in writing before your first purchase and to show it on every invoice. When it reports what you spent on Google, it has to report the exact amount Google charged, without its own fee mixed in. If your invoices show one blended number for "advertising," ask to see the two split apart. You're entitled to both.
None of these questions accuse anyone of anything. Good agencies answer them easily, because they have nothing to hide in how they're paid. For more on judging the work itself, see How to Tell If the People Running Your Ads Are Any Good. For what you owe the relationship in return, see Your Agency Cannot Give You What You Never Gave Them.
We Publish Our Rates So You Can Ask Us These Questions First
We think the fee should be the easiest part of hiring an agency to understand, so we publish ours. You can see exactly how our rates work and run every question above on us before we ever talk. If the answers fit what your business needs next, we'd be glad to help. If they don't, you'll still walk into your next agency conversation knowing what the fee is really buying.
