Customer Concentration and Revenue Quality in FDD

Customer concentration is one of the most commercially impactful findings in any Financial Due Diligence. A business where 60% of revenue comes from one customer is fundamentally different from a business with the same EBITDA derived from 200 clients. The concentration level affects valuation, financing terms, deal structure and the buyer's post-acquisition priorities.

Why Customer Concentration Matters in M&A

High concentration creates several risks that are directly relevant to the buyer:

• Revenue cliff risk: If the top customer is lost post-acquisition (through management changes, contract expiry, competitive displacement), revenue and EBITDA collapse rapidly
• Margin pressure risk: A large customer has negotiating leverage on pricing; concentrated revenue often means thin or declining margins
• Financing risk: Acquisition financing banks assess customer concentration carefully; high concentration can limit leverage available
• Multiple compression: Buyers typically apply a discount to valuation multiples for businesses with high customer concentration

How FDD Analysts Measure Concentration

Revenue Concentration Schedule

Build a table showing:

• Revenue from each named customer for the last two to three years
• Each customer's revenue as a % of total
• Year-over-year movement for each customer
• Cumulative % for the top 3, top 5, top 10 customers

Concentration Benchmarks

Broad guidelines (these vary by sector and deal context):

These thresholds are illustrative. A B2B SaaS business with one customer at 35% on a 5-year contract is very different from a services firm with one client at 35% on a 3-month rolling agreement.

Contract Review: The Key Follow-Up

When concentration is identified, the FDD analyst must review the relevant contracts:

• Contract length: How long does the relationship run? When does the contract expire?
• Renewal terms: Is it automatically renewing, or does it require active renegotiation?
• Notice period: How quickly can the customer exit?
• Exclusivity: Is the business the exclusive supplier?
• Volume commitments: Does the contract include minimum purchase volumes?
• Change of control provisions: Does the contract terminate or require consent on a change of ownership? (This is critical in M&A — a change of control clause in a major customer contract can make a deal impossible)

The Change of Control Risk

Change of control provisions in customer contracts are a major due diligence flag. If the top customer (40% of revenue) has a change of control clause allowing immediate termination, the buyer must either:

• Accept the risk (and discount the price accordingly)
• Seek consent from the customer before closing (often waived in practice, but not guaranteed)
• Negotiate specific indemnities or price protections in the SPA

The FDD team must flag all change of control provisions, and the legal DD team will assess their enforceability.

Conclusion

Customer concentration analysis sits at the intersection of FDD and commercial due diligence. The analyst who builds a rigorous concentration schedule, reviews contracts systematically and presents findings clearly helps the client make a far better-informed acquisition decision.

The Transaction Services Interview Programme (€119.99, one-time) includes customer concentration analysis with worked examples and revenue quality assessment methodology. Start today.