Client Concentration
Risk that arises when a disproportionate share of revenue comes from a small number of customers. Above 20 to 30% with a single customer, buyers generally apply a discount to the price.
Definition
Customer concentration measures how a business’s revenue is spread across its customers. Concentration is considered high when one or a few customers account for a large share of revenue — typically more than 15 to 20% for a single customer, or more than 50% for the top three combined.
In French-language Quebec documentation, you’ll see concentration de clientèle used for the same concept.
It isn’t a problem in itself for day-to-day operations. But in a sale context, customer concentration is seen as a major risk: if a large customer leaves after the transaction, a significant chunk of revenue disappears.
Why client concentration matters in a business sale
From the buyer’s perspective, every major customer not locked in by contract represents a revenue-loss risk. And that concern is legitimate — ownership transitions sometimes trigger the departure of long-standing customers who had a personal relationship with the former owner.
The impact on price is direct and measurable. A business with $500,000 in EBITDA and a well-diversified customer base (no customer above 5% of revenue) will command a higher multiple than an identical business where 35% of revenue comes from a single customer. The gap can be 0.5x to 1.5x of multiple — hundreds of thousands of dollars on the sale price.
In Quebec, customer concentration is especially common among industrial subcontractors, professional services firms, and specialized suppliers. If your business depends on a handful of large accounts, expect the buyer to request additional guarantees — retention clauses, a vendor take-back tied to retaining those customers, or even a direct price reduction.
What every seller should know
- The critical threshold is around 20 to 30% for a single customer. Beyond that, expect hard questions and a price adjustment.
- Diversifying your customer base is a long game — ideally 2 to 5 years before the sale. Adding a few customers doesn’t happen in 6 months.
- If short-term diversification isn’t possible, document the strength of the relationship: long-term contracts, renewal history, no complaints, relationships with several contacts at the customer (not just you).
- Customer concentration and owner dependency often compound — if the owner is also the main contact for the large customers, the buyer penalizes the risk twice.