Agency Client Concentration: Revenue, Contribution and Cash

Client concentration measures how much your agency depends on a small number of clients. Calculate revenue share, but also inspect the contribution, delivery hours and unpaid invoices attached to those clients. Losing a client that supplies 30% of revenue does not automatically remove 30% of profit or release 30% of usable capacity. The fictional USD examples here are operating scenarios, not universal safe thresholds or forecasts of client loss.

Quick answer

Divide each client's revenue by total agency revenue for the same period. Then model what disappears and what remains if that client leaves: avoidable costs, committed payroll, overhead, receivables and delivery hours. Compare the remaining contribution with monthly commitments. Use concentration as a scenario trigger rather than declaring a particular percentage safe for every agency.

The direct answer: a five-client month

Suppose five clients produce monthly revenue of $12,000, $8,000, $5,000, $3,000 and $2,000. Total revenue is $30,000. The largest client's share is $12,000 ÷ $30,000 = 40%. The two largest together account for $20,000 ÷ $30,000 = 66.67%.

Now assume the largest client has $4,800 of genuinely avoidable delivery costs and fees. It leaves $7,200 contribution. The other clients leave contributions of $4,800, $3,000, $1,800 and $1,200. Total agency contribution is $18,000, and the largest client supplies 40% of that contribution in this deliberately simple example.

Monthly committed overhead and a separately modeled owner-pay target total $14,000. The current scenario leaves $4,000 before taxes and unmodeled expenses. If the largest client leaves and only its $4,800 avoidable costs disappear, remaining contribution is $10,800. The agency falls $3,200 short of its $14,000 commitments.

The $12,000 revenue loss and the $3,200 operating shortfall are different measures. The gap is not solved simply by winning any new $3,200 invoice; replacement work also has costs. If new work leaves 60% contribution, revenue needed to fill the $3,200 gap is $5,333.3333, or $5,333.34 rounded upward.

These figures assume the remaining client's contributions and commitments stay unchanged. In reality, staffing, delivery dependencies and collection can change. The agency client-profitability guide provides the engagement-level cost view needed before making a loss scenario.

What changes the answer

Revenue concentration and contribution concentration can diverge. A large low-margin account might supply much of the revenue but little contribution. A smaller account with low direct cost can be more important to covering fixed commitments.

Committed payroll is often the biggest boundary. If employees remain paid after a client leaves, those salaries are not immediately avoidable. Do not remove allocated engagement labor from the scenario and also assume the team continues to be paid elsewhere without reconciliation.

Receivables create a separate exposure. A client can leave future work and also delay paying completed invoices. Track unpaid balances, due dates and actual collection assumptions. Revenue share alone cannot describe the cash at risk.

Contracted notice and scope matter, but their enforceability is a legal question beyond this worksheet. Use the actual commercial arrangements to establish the planning timeline, with appropriate review where needed. Do not assume every client will continue paying for a forecast notice period.

Freed delivery hours may not become paid work immediately. Sales lead time, specialist skills and client onboarding can delay replacement. Compare the work the team can actually deliver with the pipeline you can actually support.

Several clients can share one source of risk. Accounts from one sector, referral partner or parent organization may behave similarly. A five-client portfolio can still be concentrated operationally even when no single invoice share appears dominant.

The agency utilization guide helps distinguish available staff time from productive client-delivery capacity.

Three worked scenarios

A smaller high-contribution client leaves

Suppose the $5,000 client leaves $4,000 contribution rather than the $3,000 assumed earlier. If total agency contribution is therefore $19,000, its contribution share is $4,000 ÷ $19,000 = 21.05%, while revenue share remains 16.67%.

Losing it would reduce the $19,000 contribution to $15,000. Against $14,000 commitments, only $1,000 remains. Revenue share understated this client's importance to the operating cushion.

A delayed invoice and a future cancellation

Suppose the largest client has $6,000 unpaid completed invoices and then cancels future work. The $6,000 collection exposure is separate from the modeled $7,200 monthly contribution loss.

If unrestricted cash is $10,000 and immediate committed payments are $8,000, the agency has a $2,000 cash cushion before collecting that invoice. Assuming collection before the payments would create a $8,000 cushion instead. The timing assumption materially changes the cash plan; neither amount is guaranteed by issuing an invoice.

Build replacement contribution

Assume the $3,200 monthly contribution gap from the original loss scenario. A new $2,000 retainer leaves $1,100 contribution and requires 20 delivery hours. Three such retainers leave $3,300 and use 60 hours.

The portfolio would cover the modeled gap by $100, provided the retainers actually sell, pay and fit capacity. If only 40 suitable delivery hours are available, the proposed replacement plan is infeasible without changes. Counting prospects as signed clients would hide that uncertainty.

How to run your own numbers

Create a client table with revenue, direct avoidable costs, contribution, hours, unpaid balance and commitment dates. Use the agency break-even calculator to test the remaining portfolio and the replacement-engagement assumptions after a loss scenario.

MyBreakeven supports other currencies. Keep one currency and one period across clients. Annual contract values should not be mixed with one-month invoice revenue without a clear conversion and timing model.

Model at least three situations: current portfolio, loss of the largest contribution client and delayed payment from the largest debtor. Keep them separate before testing a combined downside. That separation makes the cause of each shortfall visible.

Write the action assumptions beside the numbers. Reducing committed spending, changing scope and selling replacement work happen on different timelines. A spreadsheet that removes all costs immediately after cancellation is an optimistic scenario unless those costs are truly avoidable at that time.

The agency profit-margin guide connects these portfolio scenarios with the agency's overall operating result.

Common mistakes

Declaring a fixed client-share percentage safe treats unlike agencies as identical. Use the share to trigger an explicit loss scenario.

Looking only at revenue misses contribution and unpaid cash. Record all three with clear definitions.

Removing committed salaries immediately after a client leaves overstates cost flexibility. Use actual staffing commitments and timing.

Assuming freed hours are instantly resold ignores lead generation and onboarding. Keep forecast replacements distinct from signed work.

Counting several related accounts as fully independent can hide sector or parent-company dependence. Record shared exposure where it is material.

Mixing annual contracts and monthly invoices produces misleading percentages. Use one observation period before dividing.

FAQs

What concentration percentage is too high?

There is no universal safe percentage in this guide. The practical test is what the loss or delay does to contribution, cash and delivery capacity. A smaller share can still be material when the operating cushion is thin.

Should I measure revenue or profit share?

Measure revenue and contribution with clearly defined costs. Final profit allocation can be sensitive to shared-cost assumptions. Client contribution helps identify what remains available to cover commitments.

Does a long contract remove the risk?

No planning model can guarantee continued payment or demand. Use actual terms and appropriate review to establish assumptions. Also examine unpaid invoices and operational dependence.

Are many small clients always better?

More clients can diversify revenue but create coordination and acquisition costs. Compare the complete portfolio workload and contribution. Client count alone does not establish a stronger agency.

Should I reject a large new client?

The worksheet helps assess exposure, price and capacity; it does not decide the commercial relationship. Model the resulting portfolio and the loss scenario. Record any staffing or cash commitments that the new account creates.

How often should I review concentration?

Review when a material account starts, leaves, changes scope or delays payment. Use consistent monthly or rolling-period figures. A regular review is useful only if the cost and receipt assumptions are kept current.

Closing takeaways

• Measure contribution and receivables alongside revenue share.
• Remove only costs that are truly avoidable in the scenario.
• Test replacement work against hours and realistic timing.
• Record shared sector or parent-account exposure.

Browse the business guide library for related planning methods.