How dependent are we on top clients?
№ 093 · Client concentration
Definition
MetricShare of trailing-12-month revenue from the top client and top 5 clients
Unit% of trailing 12-month revenue
Pareto of revenue by client. Top 5 clients above 40% revenue is danger. Build by sorting accounts by revenue and plotting cumulative. One client loss can sink the firm if too concentrated. Example: top 3 clients = 52% of revenue (high dependency).
Benchmarks
| Bottom 30% | Median | Top 30% |
|---|---|---|
| top client 25%+, top 5 clients 60%+; buyers apply a 1-2x EBITDA discount above 25% top-client share and 30-50% multiple compression above 40% | top client 15-20%, top 5 clients 45-55% | top client 10% or less, top 5 clients 30% or less |
Independent agencies and professional services firms $1M-50M revenue; thresholds drawn from agency and accounting M&A diligence practice, 2024-2026 · These are buyer diligence thresholds and advisor heuristics, not measured percentile distributions; no large-sample survey publishes the actual concentration distribution. The thresholds are consistent across independent advisory sources (top client under 15% healthy, above 25% material risk), which is why they are reported despite the absence of Tier 1 data.
Category split omitted: No two independent Tier 1-2 datasets publish concentration distributions by service line; available thresholds are cross-sector advisory heuristics.
When it looks bad
One slice of the treemap expands across consecutive periods until it dominates the view, while the long tail of smaller clients thins instead of growing.
Top client moved from 18% to 34% of revenue across four quarters; the top 3 now hold 61%, so a single loss removes a third of revenue and the anchor client knows it at every negotiation.
What to do about it
- Set a soft cap at 20% of revenue per client and route growth above it through pricing rather than volume; buyers start discounting at 25% (CT Acquisitions), so the cap protects both risk and exit value.
- Run a deliberate expansion program on clients ranked 4-10 (structured QBRs, one adjacent service cross-sold to each) so diversification comes from accounts already won, not only from expensive new logos.
- De-risk the anchor account contractually: longer notice periods, multi-year terms, and relationships across at least three client-side stakeholders so a single champion leaving is not a revenue event.
- If a sale or fundraise is plausible within two years, start diversifying now; advisors recommend bringing top-3 concentration under 40% at least 18-24 months before any process, because it is the first diligence question.
Sources
- CT Acquisitions Diligence bands: healthy = top client under 15%, top 5 under 40%, top 10 under 60%; 25-40% top-client share triggers a 1-2x EBITDA discount; above 40% compresses valuation 30-50% ctacquisitions.com ↗
- Move at Pace Buyers discount any agency where the top client exceeds 25% of revenue and some walk away above 40%; above 15% is already a concentration problem worth fixing moveatpace.com ↗
- Pharallax AI Across 160+ structural analyses of $500k-3M service firms: top client above 15% is risk worth addressing, above 25% a structural vulnerability; top 3 above 40% can cascade a bad quarter into a cash crisis pharallax.ai ↗
- Peter Kang (Barrel, citing Blair Enns and David C. Baker) Enns and Baker guidance: creative firms should run 8-15 clients and keep any single client under 25% of annual billings; Barrel's own peak concentration was 27% peterkang.com ↗
- FE International 2025 deal data: top client at 12% of revenue cited in a premium-multiple profile (10.5x applied in the worked example); low concentration is a stated multiple driver feinternational.com ↗
- FirmLever Accounting-firm marketplace data: no client above 15%, top 10 combined under 40%; a $1.8M book with one client at 28% loses half its buyer pool firmlever.com ↗