How I Evaluate Customer Concentration Risk in Service Businesses

March 1, 2026
Blog, Risk Management, Customer Strategy
1 min read
Outdoor casual headshot of Dr Connor Robertson with warm smile

When I buy a service business, one of the first numbers I study isn’t revenue, it’s customer concentration. Over the years, I’ve learned that service businesses are especially vulnerable if too much of their revenue comes from a single client or a small handful of clients. That concentration risk creates fragility, no matter how profitable the company looks on paper.

Why Customer Concentration Matters

Customer concentration matters because it:

  • Exposes the business to sudden revenue loss if a client leaves
  • Reduces negotiating leverage since big customers set terms
  • Creates fragility in valuations and financing
  • Ties the business’s future to a few relationships
  • Limits scalability if new clients aren’t diversified

A company can look like it’s thriving, but if 60% of its revenue is tied to one customer, I know the risk is high.

My Early Mistakes

In one acquisition, I overlooked concentration because the client had been with the company for 15 years. Six months after closing, that client left. Revenue dropped nearly in half.

In another case, I believed assurances that a top client was “loyal.” But loyalty didn’t protect against budget cuts. The business was devastated when the client reduced spending.

Both mistakes taught me that customer concentration must be measured, not assumed safe.

How I Evaluate Concentration

During diligence, I:

  • Review the percentage of revenue from the top one, three, and five clients
  • Analyze the length and terms of contracts
  • Test whether relationships are tied to the seller personally
  • Study renewal rates and client churn history
  • Interview customers when possible to gauge loyalty

How I Mitigate Concentration Risk

If I see high risk, I:

  • Adjust valuation downward
  • Structure earnouts based on client retention
  • Require seller involvement in transition
  • Plan diversification strategies post-acquisition

Final Thoughts

I’ve learned that customer concentration risk is one of the most dangerous blind spots in service businesses. That’s why I measure it carefully, structure deals around it, and prioritize diversification.

I continue sharing my acquisition strategies at drconnorrobertson.com, where I explain how I manage risks like concentration in real-world deals.

Related Articles by Dr. Connor Robertson

You may also like

Contact Connor