What it means
A reinsurer's whole business model rests on diversification. By writing slices of risk from hundreds of insurers across many countries, product lines and hazards, it can absorb a bad year in one market with a good year in another.
That spread is what allows it to charge less for a risk than the ceding insurer would need to hold in capital against it. Reinsurers earn money in two ways that are worth separating.
The first is underwriting profit, the margin between premiums received and the claims plus expenses paid out; the second is investment income earned on premiums held between collection and claim payment, often called the float. In soft markets a reinsurer may accept a thin or negative underwriting margin because the investment return still makes the deal worthwhile.
The headline measure of a reinsurer's performance is the combined ratio, which adds claims, ceding commissions and internal expenses and divides the total by premium earned. Anything below 100% means the business made money before investment returns are counted, and anything above means it lost money on underwriting.
Reinsurers themselves buy protection, a practice called retrocession, passing on portions of their own exposure to other reinsurers or to capital markets through instruments such as catastrophe bonds. This creates a chain of risk sharing that spreads a single hurricane across dozens of balance sheets worldwide.
Credit quality is the reinsurer's product as much as its price. A cedant is buying a promise that may not be called on for years, so ratings agencies, capital strength and a record of paying disputed claims without argument carry real commercial weight when treaties are renewed.
In practice
Real-world examples.
Example
A global reinsurer signs treaties with 40 different regional insurers across four continents, so that a severe earthquake in one country affects only a small slice of its portfolio. Its diversification lets it hold less capital per unit of risk than any one of its clients could.
Example
A life reinsurer takes on the mortality risk of a mid sized life office's new policies, leaving the insurer to handle sales and administration. The insurer keeps the customer relationship while the reinsurer carries the exposure to people dying earlier than the pricing assumed.
Example
A reinsurer facing an unusually concentrated exposure to a single hurricane-prone region issues a catastrophe bond, passing $250,000,000 of that exposure to investors who receive an attractive coupon and lose principal only if a named storm triggers the contract.
Think of it
“Reinsurer is the insurance company that insures insurers-taking risk from primary carriers.
Formula
Calculation
Combined ratio = (claims incurred + ceding commission + operating expenses) / premium earned
A reinsurer accepts a 30% quota share of a property insurer's book and receives $15,000,000 of ceded premium for the year. It pays a ceding commission of 25%, which is $15,000,000 x 0.25 = $3,750,000, and its share of claims comes to $9,600,000. Its own operating expenses for administering the treaty are $600,000.
Total costs are $3,750,000 + $9,600,000 + $600,000 = $13,950,000. The combined ratio is $13,950,000 / $15,000,000 = 93%, so the underwriting profit is $15,000,000 - $13,950,000 = $1,050,000. If the reinsurer also earns $450,000 investing the premium before claims are settled, the treaty contributes $1,050,000 + $450,000 = $1,500,000 in total.Case study
Seen in the real world.
This is an illustrative and clearly fictional example. Meridian Atlas Re, an invented mid sized reinsurer, spent three years growing quickly by accepting quota share treaties from small insurers at a ceding commission of 32%, well above the market norm of 25%.
The strategy worked while claims stayed benign, but the commission alone consumed almost a third of every premium dollar before a single claim was paid. When claims rose to 68% of premium in a difficult year, the fictional combined ratio reached 106% and the company reported an underwriting loss for the first time in its history.
Meridian Atlas Re's illustrative response was to cut the ceding commission back to 26% at renewal and walk away from the third of its book that would not accept the change. Premium income fell by 30% but the combined ratio returned below 97% within two years.
Watch out
Common mistakes.
- Assuming a reinsurer is simply a bigger insurer, when its customers are insurance companies rather than households or businesses.
- Reading a combined ratio above 100% as automatic failure, without checking whether investment income on the float still leaves the reinsurer profitable overall.
- Overlooking retrocession, and so underestimating how far a single large catastrophe can spread through the wider financial system.
Questions
People also ask.
How does a reinsurer decide what to charge?
It models the expected claims, adds a loading for volatility and expenses, and prices the capital it must hold against the risk.
Why do reinsurance prices swing so much between years?
Capacity contracts sharply after major catastrophe losses and rebuilds when capital returns, producing the cycle of hard and soft markets.
Does a reinsurer ever deal directly with the policyholder?
Almost never, because its contract is with the ceding insurer, which remains solely responsible for handling and paying claims.
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