loss ratio

American  

noun

Insurance.

1. the ratio of the losses paid or accrued by an insurer to premiums earned, usually for a period of one year.

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loss ratio British  

noun

1. the ratio of the annual losses sustained to the premiums received by an insurance company

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Etymology

Origin of loss ratio

First recorded in 1925–30

Example Sentences

Oscar’s medical loss ratio, a measure of the proportion of premiums that the insurer pays out on medical bills, rose sharply to 95.4%, well in excess of the average analyst target of 91.1%.

From The Wall Street Journal • Feb. 10, 2026

That estimate puts the loss ratio about 2 percentage points higher than the same quarter a year prior.

From Barron's • Feb. 10, 2026

The trick hinges on a seemingly noble safeguard known as the medical loss ratio.

From MarketWatch • Dec. 10, 2025

The company’s medical loss ratio is anticipated to be 84.3%, an increase from 82.8% in the same quarter last year.

From Barron's • Oct. 29, 2025

Business conditions were uncertain, overhead charges extraordinarily increased, the loss ratio large and bidding fair to cut their bonus down to nothing.

From Broken to the Plow by Dobie, Charles Caldwell