Diversify carriers and lines
When it may fit: One source dominates.
Evidence needed: Carrier appetites and markets.
Trade-off: Takes years to build.
Insurance Intelligence Brief
How to Evaluate Agency Revenue Concentration
An agency or brokerage that earns most of its revenue from one carrier, one line or a few clients carries risk that does not show up in its income statement.
1. The business problem
If our largest source of revenue changed its terms or left, how badly would we be hurt?
Agency revenue comes from commissions, fees and sometimes contingent payments, and it is usually concentrated: a handful of carriers, a few product lines and a small number of large clients often account for most of it.
Concentration carries risks of a carrier changing commission or appetite, a line becoming unprofitable, or a large client moving. Measuring it is the first step in managing it.
2. What the evidence can reveal
A concentration review shows revenue by several cuts:
- Calculated Revenue by carrier, product line and client, as shares of the total.
- Calculated Profit by the same cuts, since commission rates and service costs differ.
- Calculated The effect on profit of losing the largest carrier, line or client.
- Information gap Contract terms, termination rights, contingent commission arrangements and alternatives available.
Measuring by profit, not only by revenue, avoids over-valuing relationships that cost a lot to serve.
3. Investigate the problem
The synthetic insurer is a carrier, not an agency, but its book shows what an agency’s product-line concentration would look like from the other side. Calculated Personal Auto is about 41% of earned premium ($33.8M of $82.5M), Homeowners about 33%, Small Commercial about 19% and Specialty & Umbrella about 8%. Auto and homeowners together are about 74%.
Calculated The carrier’s cost of distribution gives a sense of what is at stake: acquisition costs were $10.5M, about 12.7% of earned premium, up 9.4% in a year when premium rose 11.5%. Illustrative For an agency with a similar book, if one line were 41% of its revenue, a carrier’s tightening of appetite or a drop in that line’s commission would hit about two-fifths of income at once.
Hypothesis Because Personal Auto’s loss ratio rose to 74.3%, its largest line is also the one most likely to face rate action, tighter underwriting or reduced carrier appetite, which would affect agencies selling it. Information gap The demo has no agency or carrier-contract data. An agency should list its revenue by carrier and line, with contract terms and renewal dates, and test what a 10% loss in each would do to profit.
4. Explore the interactive experience
Investigate it yourself.
Insurance Portfolio Explorer: a portfolio dashboard with loss, expense and combined ratios, a scenario simulator for rate, volume, frequency and severity, evidence-linked answers from APIS, and a sample brief, all on synthetic data.
The experience below is built on a synthetic insurer, “Demo Mutual Insurance.” It uses no policyholder, producer or agency data of any kind, so it is used to show the portfolio economics that agency and brokerage decisions connect to. Every figure is illustrative.
- In the product table, sort by Earned premium. What share of the book is in the top two lines?
- Select Personal Auto. Its loss ratio rose. What might that mean for the agencies that sell it?
- Ask APIS how sensitive the underwriting result is to loss ratio.
5. Evaluate possible solutions
Managing concentration is gradual but worthwhile.
6. What leadership should do next
Questions to answer
- What share of revenue and profit comes from each carrier and line?
- Which relationships are at risk?
- What would losing one cost?
- What alternatives exist?
Data to gather
- Revenue and profit by carrier, line and client
- Contracts and renewal dates
- Market alternatives
- Client list
Steps to take
- Map concentration.
- Stress-test the top three.
- Set diversification goals.
- Review annually.
7. Engage Two Pillars
Investigate Performance Across Your Insurance Business
Two Pillars can help carriers, agencies and brokerages investigate portfolio, claims operations, agency economics and process improvement using your own data. This demo uses no policyholder data. A good first step is a revenue concentration map for your agency by carrier, line and client, with a stress test.
Sources and data notes
- The organization, its figures, and every number in this article and its interactive experience are synthetic and illustrative. They are not real data, a benchmark, or a forecast.
- Reviewed October 2026. This article describes an approach to investigation. It does not replace review by qualified professionals.