Combined Ratio Calculator
Loss ratio plus expense ratio: the underwriting verdict.
Combined ratio
Estimates for planning only, not financial advice.
The combined ratio is the insurance industry\'s bottom line for underwriting: claims plus expenses as a percentage of premiums. With $1,000,000 of earned premiums, $650,000 of incurred losses, and $280,000 of underwriting expenses, the loss ratio is 65%, the expense ratio is 28%, and the combined ratio is 93%: 7 cents of underwriting profit per premium dollar. Add $50,000 of investment income and total profit reaches $120,000. This calculator splits every piece so you can see which half needs work.
How to Use This Calculator
Enter earned premiums (revenue actually recognized for the period), incurred losses including loss adjustment expenses (claims paid plus reserve changes plus claim-handling costs), and underwriting expenses (commissions, salaries, overhead). Optionally add investment income to see the full operating picture. The results show loss ratio, expense ratio, combined ratio with a verdict, underwriting profit in dollars, and the operating ratio net of investments.
Enter earned premiums and incurred losses with LAE. Use earned, not written, premiums for the loss side.
Enter underwriting expenses and investment income for the complete picture.
Read the combined ratio and the split. Fix the worse half first: pricing and risk selection move the loss ratio, efficiency moves the expense ratio.
The Combined Ratio Formulas
The operating ratio is the number that captures the float business model: a 93% combined ratio minus 5% of investment income per premium dollar is an 88% operating ratio. This is why insurers can thrive in soft markets that look unprofitable on underwriting alone. But the discipline runs the other way too: when investment income is strong, it tempts underpricing, and the combined ratio is the metric that keeps underwriting honest regardless of market returns.
Worked Example
A regional auto insurer earns $1,000,000 of premiums in the quarter. Incurred losses plus claim-handling costs total $650,000: a 65% loss ratio. Commissions, salaries, and overhead total $280,000: a 28% expense ratio. Combined ratio: 93%. Underwriting profit: $1,000,000 x 7% = $70,000. Investment income of $50,000 lifts total operating profit to $120,000, an 88% operating ratio. Management\'s read: underwriting is genuinely profitable, and the 28% expense ratio is the improvement lever, since direct competitors run closer to 24%.
Benchmarks by Line
| Line of business | Typical combined ratio | Driver |
|---|---|---|
| Personal auto (good operators) | 90 to 96% | Scale, data, pricing precision |
| Homeowners | 95 to 105% | Catastrophe volatility |
| Workers compensation | 90 to 100% | Long-tail reserves, medical inflation |
| Commercial liability | 95 to 105% | Social inflation, large verdicts |
Single-period ratios mislead in catastrophe-exposed lines: one quiet hurricane season flatters, one bad season devastates. Judge those lines on 5-year averages and the ex-catastrophe ratio. Reserve movements deserve the same skepticism: a 92% calendar-year ratio built on reserve releases is weaker than a 96% accident-year ratio on honest reserves. For adjacent financial analysis, our cash flow to debt calculator tests balance-sheet strength, our business budget planner builds the expense plan, and our margin calculator handles the non-insurance version of the same math.
Estimates for planning only, not financial advice.
Frequently Asked Questions
What is the combined ratio in insurance?
The combined ratio measures underwriting profitability: (incurred losses + loss adjustment expenses + underwriting expenses) divided by earned premiums, usually expressed as loss ratio plus expense ratio. A 93% combined ratio means the insurer spends 93 cents on claims and expenses for every dollar of premium, keeping 7 cents of underwriting profit. Below 100% is profitable; above is an underwriting loss.
What is the combined ratio formula?
Combined ratio = loss ratio + expense ratio, where loss ratio = (incurred losses + loss adjustment expenses) / earned premiums and expense ratio = underwriting expenses / written premiums. With a 65% loss ratio and a 28% expense ratio, the combined ratio is 93%. Note the subtle denominator difference: losses over earned premiums, expenses over written premiums.
What is a good combined ratio?
Anything under 100% means profitable underwriting, and the lower the better. Excellent personal-lines insurers run in the low 90s; 95% to 99% is solid; 100% to 105% is a mild underwriting loss that investment income may offset. Sustained ratios above 105% signal pricing or risk selection problems that investment returns cannot paper over forever.
What is the difference between loss ratio and combined ratio?
The loss ratio covers claims only: what the insurer pays out versus premiums earned. The combined ratio adds the expense ratio (commissions, salaries, overhead), giving the full underwriting picture. An insurer can have a great 60% loss ratio and still lose money with a 45% expense ratio. Both halves need discipline; great claims management cannot rescue bloated operations.
Can an insurer be profitable with a combined ratio over 100%?
Yes, through investment income. Insurers collect premiums upfront and pay claims later, investing the "float" in between. A 102% combined ratio with strong investment returns can still produce overall profit. But relying on investments to subsidize underwriting is fragile: when markets fall, both sides bleed at once, which is exactly when the float is most needed.
What is the expense ratio made of?
Commissions to agents and brokers (often the biggest piece), employee salaries, rent, technology, marketing, and premium taxes. Direct writers with no agent commissions run expense ratios in the 20s; agency-based insurers run in the 30s. Expense ratio is the most controllable half of the combined ratio, which is why efficiency programs target it first.
How do catastrophes affect the combined ratio?
Violently and temporarily. A major hurricane can add 10 to 30 points to affected insurers' loss ratios in a single quarter. Analysts therefore look at the "ex-cat" or accident-year combined ratio to judge underlying underwriting, treating catastrophes as a separate modeled cost. Reinsurance exists precisely to smooth these spikes.
What is the difference between calendar year and accident year combined ratio?
Calendar year includes reserve adjustments for old claims, so prior-year reserve releases or strengthening flow through it. Accident year isolates the current underwriting year's performance. A calendar-year ratio flattered by reserve releases can hide deteriorating current pricing. Sophisticated analysis always checks both.
Why do mutual insurers target different combined ratios than public ones?
Public insurers face quarterly earnings pressure to keep the ratio low and stable. Mutuals, owned by policyholders, can tolerate higher ratios in exchange for lower premiums or bigger dividends to members. The "right" ratio depends on ownership structure and strategy, not just the number itself.
How does the combined ratio relate to ROE?
Roughly: underwriting profit (100% minus combined ratio, times premiums) plus investment income, minus taxes, divided by equity. A 93% combined ratio on $1 billion of premiums is $70 million of underwriting profit before investments. Investing the float amplifies it: the same underwriting margin produces higher ROE at higher premium-to-surplus ratios, which is also why thinly capitalized insurers are fragile.