How many clients per account manager: the ratio most agencies use, and the hours arithmetic that should replace it

The question usually arrives in one of two forms. Either an account manager has just resigned and you need to know whether the replacement can carry their fourteen accounts, or you are about to sign three new clients and want to know whether that means a hire. Both are capacity questions, and a ratio copied from someone else's agency answers neither of them.

The number everyone quotes

Karl Sakas, who advises agencies on operations, puts a dedicated account manager at four to eight accounts, with the caveat that the same person might carry six to eight easy-going clients or only two or three needy ones. He also ties the ratio to budget: an account manager might hold eight clients spending $5,000 a month and only one or two spending $100,000.

Databox surveyed 48 agencies on the same question and found that almost 70% said their account managers handle fewer than ten clients each, while more than 10% reported fifteen or more per manager.

Those are the two figures that trace to a named source. The ranges you see elsewhere, like eight to fifteen for digital agencies or ten to twelve for paid media, are practitioner rules of thumb that have been repeated until they read as research. The spread between a Sakas two and a Databox fifteen is the real finding: the ratio depends on the account, and a single number is a guess dressed up as a benchmark.

Work it out from hours instead

The account manager ratio that fits your agency falls out of three numbers you can measure in a month.

First, the account management hours one representative client actually consumes. Pick an account in the middle of your book, and for four weeks log every hour the account manager puts against it: calls, prep, follow-ups, the internal meeting about it, the report, the message thread at 6pm. Most agencies that do this for the first time find the honest figure is roughly double what the retainer assumed, because account management is the most common single omission when a retainer gets priced.

Second, the manager's available client-facing hours. Start from roughly 1,700 productive hours a year, which is what a full-time person has once holiday, public holidays and sickness are out, and that is about 140 hours a month. An account manager who also sells, trains or manages people is a hybrid role, and the utilization rate a hybrid role can sustain is 60% to 70%, so plan on 85 to 100 client-facing hours a month rather than 140.

Third, divide. If a representative account consumes twelve hours a month of account management, the manager carries seven or eight of them. If it consumes twenty, the manager carries four or five, and the published four to eight range starts to look optimistic for a high-touch book. Run the same arithmetic for your largest account on its own, because a client at 25% of revenue often consumes a third of a manager by itself.

Cost the hours before you set the ratio

A ratio that fits the calendar can still lose money, so load the hours at fully-burdened cost before you decide anything. That is salary multiplied by 1.25 to 1.4, divided by about 1,700 hours. An account manager on £45,000 costs roughly £33 to £37 an hour loaded, so twelve hours a month of account management is £400 to £440 that has to sit inside the retainer's delivery cost before gross margin is calculated.

On a £3,000 retainer that is 13% to 15% of the fee going to account management alone, before any delivery happens. On a £10,000 retainer the same hours are 4%. This is why the ratio should be set per tier of account rather than per manager: a book of small retainers needs a higher ratio to hold a 50% gross margin, and the only ways to get there are a lighter service model for that tier or a higher price. The effective hourly rate on each account tells you which, and the retainer pricing method covers the arithmetic.

The signals that the ratio is wrong

Three things show up before churn does. Reports go out late, because reporting is the first thing a manager drops when the calendar fills. Clients start emailing the founder, because the manager stopped answering within a day. And the manager's logged hours against the smallest accounts fall toward zero, which reads as efficiency on a utilization report and surfaces as a cancellation two quarters later.

When you see those, the fix is rarely to lecture the manager about time management. Either the hours per account are higher than the retainer assumed, which is a pricing problem, or the book has grown past what the arithmetic allows, which is a hiring problem with a date on it. The capacity planning article covers how to set that date before the resignation sets it for you.

What it looks like when it works

Fraggell Productions put a pod-lead layer between the founders and daily production, with each pod owning its accounts and its margin, and held gross margin above 70% on every pod while growing from £23k to £110k a month over 24 months. ZeroTo1 raised average contract value from $8k to $20k a month while scaling from 11 to 75 people, which moved every account manager onto a book where the hours were paid for.

If you want to know whether your account managers are carrying a book the arithmetic supports, the diagnostic is where we start, and it covers the other three constraints alongside this one.

Read next

• Agency utilization rate: the target, how to calculate it, and why 100% is a warning sign
• Agency pod structure: how to grow by cloning a unit instead of redesigning the org chart