Diagnostic Tool
Customer Concentration Risk Calculator
This diagnostic measures the degree to which a business depends on a small number of customers for its revenue. High customer concentration creates a structural vulnerability where the relationship management, renewal decisions, and commercial terms of one or two counterparties can determine the financial outcome of the entire business.
In practice, customer concentration builds gradually. Businesses often grow by deepening relationships with successful clients, and the revenue share of key accounts expands over time. The commercial logic makes sense at the individual relationship level, but the cumulative effect is a revenue base that is far more fragile than the headline growth rate suggests.
Understanding concentration risk matters because it directly affects negotiating leverage, pricing discipline, and the ability to absorb customer-level shocks. A business where two customers represent sixty percent of revenue is structurally dependent on those relationships in a way that constrains every major commercial and operational decision.
Revenue base and top customer shares
Total annual revenue across all customers.
Operating profit as a percentage of revenue.
Largest customer's revenue as a percentage of total.
Second largest customer as a percentage of total revenue.
Third largest customer as a percentage of total revenue.
Total number of active customers across all revenue.
Remaining contract term for the largest customer if applicable.
Gross margin earned on the largest customer relationship.
Annual percentage of customers lost on average across the base.
Many of the inputs requested by this diagnostic are metrics that disciplined operators typically monitor through internal management reporting. If a number requested here is not immediately available it often indicates that the current reporting structure does not isolate that metric clearly. Businesses operating with strong financial visibility normally track these figures regularly because they influence pricing decisions, supplier negotiations, operational planning, capital allocation, and risk management. Part of the work performed by MJB Strategic often involves helping companies design internal reporting structures that surface these metrics consistently so management can make better operational decisions.