Customer Concentration

What Is Customer Concentration?

Customer concentration measures how much of a business’s revenue comes from its top customers. A business where one customer accounts for 40% of revenue has high concentration; a business where the top 10 customers collectively account for 20% of revenue has low concentration.

There is no universal threshold, but buyers typically flag concentration risk when a single customer exceeds 10–15% of revenue, and apply material valuation discounts or deal structure adjustments when a single customer exceeds 20–25%.

Why Customer Concentration Matters in M&A

Concentrated revenue creates deal risk on multiple dimensions:

Loss risk — if a key customer leaves post-close, the business may not achieve the earnings on which the purchase price was based
Change-of-control clauses — many customer contracts include provisions allowing termination or renegotiation on a change of ownership
Earnout risk — if revenue targets are underpinned by a concentrated customer, earnout achievement is more fragile
Negotiating leverage — large customers often know their importance and extract pricing or terms concessions over time

How Buyers Address Customer Concentration

Buyers use several tools to manage concentration risk:

Purchase price adjustments — applying a lower multiple to concentrated revenue streams
Earnout structures — tying a portion of purchase price to retention of key customers post-close
Representations and warranties — requiring the seller to represent that key customer relationships are in good standing and no termination is anticipated
Customer relationship diligence — direct buyer-seller-customer conversations during the process to assess relationship quality