Insurance Float Is Money You Hold Before You Have to Pay It Out
Insurers collect premiums today against claims settled later, and they invest the money in between. That gap is the reason insurance has produced some of the great compounding records in finance.
The Mechanism
An insurer collects premiums upfront and pays claims later, sometimes much later. Between collection and payment it holds the money and invests it. That pool is called float.
Float is not profit and it is not the insurer's money in any permanent sense. It represents obligations that will eventually be paid. But while it is held, the investment income belongs to the insurer.
Why Duration Matters
The length of the gap varies enormously by line of business, and that variation drives the economics.
Automobile and property insurance settle quickly, often within months, so float is short and turns over rapidly. Certain liability lines can take many years to settle, because a claim may not be reported for years and litigation extends the timeline further. Those long tail lines generate float that can be invested for extended periods.
Longer duration float is more valuable, and it is also more dangerous, because the ultimate cost is estimated for years before it is known.
Float is borrowed money whose cost is the underwriting result. Underwrite at a profit and the borrowing cost is negative, which is the closest thing to free leverage in finance.
The Combined Ratio
Whether float is a gift or a trap is measured by the combined ratio, which adds the loss ratio, meaning claims paid as a percentage of premiums, to the expense ratio, meaning operating costs as a percentage of premiums.
A combined ratio below 100 percent means the insurer made money on underwriting before any investment income. In that case the float was obtained at a negative cost, and the insurer is being paid to hold other people's money.
Above 100 percent means underwriting lost money, and the float carries a genuine cost. It can still be worthwhile if investment returns exceed that cost, but the margin of safety is thinner and the model depends on markets cooperating.
Why Most Insurers Do Not Achieve It
Insurance is close to a commodity and competition is intense. When capital is abundant, insurers compete on price, and premiums fall below what the expected claims justify. This is called a soft market.
The discipline required to write less business when pricing is inadequate is unusual, because market share is visible immediately and underwriting losses appear years later when claims develop. Management compensated on growth faces an obvious temptation.
The insurers that have compounded capital over decades are generally those willing to shrink dramatically during soft markets and expand aggressively after a catastrophe has removed industry capital and raised prices.
Where the Estimates Hide
The analytical difficulty is that claims not yet settled are estimates. Insurers set aside reserves against expected future claims, and those reserves are management judgments.
Under reserving flatters current earnings and creates a problem that emerges later as reserve strengthening. Watching whether an insurer's prior year reserves develop favorably or unfavorably over time is the single best available check on whether its reported profits have been real.
The Bottom Line
Float is investable money held against future claims, and its value depends entirely on underwriting discipline. Check the combined ratio and prior year reserve development before believing any insurer's earnings.