Every buyer assumes some attrition. Every seller assumes less than the buyer does. The gap between those two assumptions is one of the quieter reasons deals feel disappointing afterwards, because it is rarely argued about openly at the negotiating table and it lands entirely on the seller when the price is measured on income retained after the event.
This article is about who leaves, why, and what actually reduces it.
Why it matters more than it used to
Because of how the price is constructed. Recurring income accounts for over 80% of offers on Gunner & Co's figures. When the consideration is a multiple of recurring income and part of it is deferred against retention, client attrition is not a soft loss of goodwill. It is a direct arithmetic reduction of what you are paid, and it happens during the period when you have the least control over the client experience.
If your deferred element is measured at a date, a client who drifts away in month seven costs you the same as a client who resigned in month one.
Who actually leaves
Attrition is not random, and it is not usually about price.
Clients whose relationship was with you personally, not with the firm. The ones who ring your mobile. They are commonly your longest-standing and largest clients, which is why attrition tends to be worse by value than by headcount, and why a simple client-count retention figure flatters the picture.
Clients who were already half out of the door. Disengaged, under-serviced, not seen for two years. The sale is the prompt rather than the cause. These are frequently the ones a buyer's diligence identifies first.
Clients who dislike what they are moving to. A different service proposition, a higher ongoing charge, a model portfolio replacing something bespoke, a centralised proposition replacing a local relationship. The FCA's consolidation review is direct that poorly managed integration risks poor consumer outcomes; from the client's chair this is what that looks like.
Clients who follow an adviser. If an adviser leaves and their covenants are weak or absent, some of their clients go with them. This is why keeping your advisers through a sale is a pricing issue.
Clients who never actually received the letter. Wrong address, unopened email, a form never returned. Administrative rather than emotional, entirely preventable, and a meaningful share of the total. The mechanics are in how clients actually transfer.
That last category is worth dwelling on. A material part of what is recorded as attrition is not a decision by anyone. It is paperwork that nobody chased.
What reduces it
Tell them properly, once, before anything changes. The strongest predictor of whether a client stays is whether the first they heard of it was from you, in good time, with the new arrangement explained. Telling your clients covers how.
Introduce the successor by name. A client who has met, or at least spoken to, the person taking over is materially more likely to stay than one who has been told about a firm. This is the main practical purpose of the handover period covered in staying on after completion.
Be honest about fee changes. If the ongoing charge is going up, saying so plainly loses fewer clients than letting them find it on a statement. Discovering an unannounced increase converts a neutral client into a departing one.
Segment the effort. Not every client needs the same treatment. The top group by value, and anyone whose relationship is with you personally, warrant a call rather than a letter. This is the highest-return work in the entire transfer.
Clean the data first. Contact details, plan records, servicing status. Cheap to fix beforehand, impossible to fix during. Also the thing that most affects the price in the first place, per why data quality determines price.
What to do about it in the negotiation
Three things, all of which are easier to agree before heads of terms than after.
Ask how the buyer defines a retained client. Still paying an ongoing charge at a date, or still on the books? The definitions differ and so does the number.
Ask what happens to clients in transit. A client who has agreed to move but whose adviser charge has not yet been re-instructed by the provider should not count as lost. If the agreement is silent, the risk is yours.
Push the measurement date out, or the weighting down. A retention measure taken early in the integration captures the worst period, when the buyer's changes are landing and the relationships are newest.
The honest part
Some clients will leave and it will feel personal, and to a degree it is: they came for you and you are not there. That is not a failure of the sale, it is a fact about advice. The FCA's expectations of firms selling client banks are clear that the client bank is the firm's asset, but no agreement obliges a client to stay with anyone.
What you can control is that nobody leaves for a reason that was avoidable: not because they never got the letter, not because the fee changed without warning, not because the first they knew was a stranger's email. Attrition driven by preference is the cost of selling. Attrition driven by poor handover is a cost you paid for and did not need to.
Putting a number on it
Vague anxiety about attrition is less useful than an estimate, and an estimate is not difficult to build.
Start with the range the firm sits in. Running your recurring income through this site's free IFA valuation calculator gives a range rather than a figure, which is the right shape for this exercise because attrition is one of the things that decides where in the range you land.
Then segment your own client bank by two questions: whose relationship is this really, and how engaged are they? Four groups fall out of that, and they behave very differently.
Institutional and engaged. Serviced by the firm, seen regularly, know more than one person. These largely stay, and they are the reason a well-run firm sells well.
Institutional but disengaged. Not seen for a long time, paying an ongoing charge, unlikely to notice the change and unlikely to respond to a form. The risk here is administrative rather than emotional, and it is fixable with effort.
Personal and engaged. Your clients, in the real sense. High value, high risk, and the group where a call from you and a joint meeting with the successor changes the outcome.
Personal and disengaged. The hardest group, and often the one quietly written off.
Estimating a retention rate for each group and weighting by income gives you a figure that is far better than a guess. More usefully, it tells you where effort actually pays: almost all of it belongs in the third group, which is rarely the group that gets the attention.
What to do with the answer
Two things.
Use it in the negotiation, honestly. A seller who arrives with a segmented view of their own client bank and a realistic retention estimate is a seller who looks prepared, and preparation is what the market has been paying a premium for. Attempting to conceal a concentration of personal relationships does not work: diligence finds it, and finding it late costs more than disclosing it early.
And use it to decide how hard to resist a retention-based structure. If your own analysis says the great majority of income is institutional and engaged, a retention measure is a bet you are likely to win and you can afford to accept one in exchange for a better headline. If the analysis says a large share of the income sits in the personal groups, a retention measure is a bet on your own successor's performance, and moving consideration to completion is worth a real discount.
That is the useful reframing. Attrition is not simply a risk to be worried about. It is a fact about your firm that you can measure before anyone else does, and measuring it first is what lets you choose the structure rather than be handed one.
Read next: telling your clients, when an earn-out underperforms, and the rest of the people and clients pillar.