Loss Ratio

What Is a Loss Ratio?

A loss ratio measures how much of an insurance company's earned premium is consumed by claims. Insurers collect premiums from policyholders and, in return, promise to pay for covered losses such as car accidents, property damage, or medical bills. The loss ratio shows what share of those premiums went toward those losses, making it one of the most basic gauges of an insurer's core business.

How It Is Calculated

Loss Ratio = Incurred Losses / Earned Premiums × 100%

Incurred losses include claims paid during a period plus an estimate for claims that have been reported but not yet settled, often held as a loss reserve. Earned premiums are the portion of premiums that corresponds to coverage already provided during the period, not the full amount billed.

For example, suppose a hypothetical insurer earns $200 million in premiums over a year and incurs $130 million in losses. Its loss ratio would be 65 percent, meaning 65 cents of every premium dollar went to claims. The remaining money must cover underwriting expenses, administrative costs, and profit.

Why It Matters to Investors

Loss ratio is usually read alongside the expense ratio to produce the combined ratio. A combined ratio below 100 percent generally indicates an underwriting profit, while a figure above 100 percent indicates an underwriting loss, although investment income can still make the company profitable overall. Rising loss ratios may signal higher claims costs, more severe weather or accident activity, or pricing that has not kept up with losses.

Loss ratios also have limits. Results can be distorted by reserve estimates that prove too high or too low, and ratios can swing widely from one year to the next because of catastrophic events. Comparing loss ratios is most useful among insurers writing similar lines of business, since auto, health, and property coverage behave very differently.