The simple version

Add up what a carrier paid in claims and what it spent running the business, then set that against the premiums it collected. That share, written as a percentage, is the figure.

At 100 the policies came out exactly level. Below 100 the policy book made money and above 100 it lost money, which is why a rise is bad news here.

It says nothing about what the firm earned on the money it holds in the meantime. That is the other half of the business and a separate line.

The numbers

• Cincinnati Financial Corporation reported a 90.9 percent third-quarter 2026 property casualty combined ratio, increased from 88.2 percent for the third quarter of 2025. Form 8-K exhibit filed with the SEC on October 26, 2026.
• The same release reports a $663 million decrease in third-quarter 2026 net income compared with the third quarter of 2025.
• It attributes that decrease to several things, in its own words including after-tax net decreases of $657 million from net investment gains and $41 million from property casualty underwriting profit, partially offset by an increase of $24 million from investment income. The release says including, so those are some of the components and not a complete list; they do not add up to the total and we have not treated them as though they do.
• Other figures in the same release: 2 percent growth in third-quarter net written premiums, $315 million of third-quarter property casualty new business written premiums, down 12 percent, and book value per share of $105.42 at September 30, 2026, up $3.07 since year-end.
• The release also carries a nine-month combined ratio and a long-term target range for the figure, both inside a statement attributed to a named executive. We do not quote or restate those, so this article uses only the quarterly figure and the year-earlier comparison, which the release states in its own unattributed prose.
• Read in the filing itself at the SEC on October 27, 2026. Accession 0000020286-26-000059, exhibit 99.1.

Why the figure and the profit line can disagree

A carrier collects premiums now and pays claims later, so it holds a large pile of other people's money in between and invests it. Two businesses, one firm.

This figure grades only the policy book. Gains and losses on the invested pile sit outside it entirely, which is how the policy side can get modestly worse while the profit line moves by a far larger amount in either direction.

The release above shows exactly that shape. The policy side went from 88.2 to 90.9, a change of under three points, while the largest single component it names in the profit decline is investment gains rather than policies.

The actual math on what 90.9 leaves over

Take the figure away from 100 and you have the share of each premium dollar left after claims and expenses. At 90.9 that share is 9.1.

A year earlier the figure was 88.2, which left 11.8. So the margin on policies narrowed by 2.7 points of each premium dollar, which is the same thing as the ratio rising 2.7 points.

Both of those takeaways from 100 are ours. The two ratios are the firm's, and so is the statement that the second one increased from the first.

What this means

If you see this figure in a headline, read the direction before the level. A number in the eighties that rose is a worse quarter for the policy business than a number in the nineties that fell.

It also explains why your renewal can rise in a year the insurer reported a good figure. The figure is backward-looking across a whole book of business, and your premium is priced off what the company expects next.

The transferable habit is to ask which direction is good before reading any ratio. A handful of financial measures are inverted like this, and the headline almost never says so.

What this is NOT

This article explains what a property casualty combined ratio measures and why it moves in the opposite direction from most reported percentages, using Cincinnati Financial Corporation's third-quarter 2026 Form 8-K exhibit filed on October 26, 2026 and read on October 27, 2026 as the worked example. It is not investment advice about that company or any insurer, it is not a recommendation to buy, sell or switch any insurance policy, and we do not give personalized advice. It is not a judgment that the quarter was good or bad; we report the two ratios the company printed and the direction it stated between them, and nothing more. The nine-month ratio and the company's long-term target range for this figure appear in the release only inside a statement attributed to a named executive, so we have deliberately left both out rather than restate a person's words. The subtractions from 100 in the math section are ours. The components of the net income decline are quoted as the release gives them, introduced by its own word including, and we have not added them up or inferred a residual. It says nothing about how any insurer prices an individual policy, nothing about reserves or reserve adequacy, and nothing about where this or any ratio goes next. This is not a political endorsement or criticism of anyone.

Sources

• Cincinnati Financial Corporation, Form 8-K Exhibit 99.1, third quarter 2026 results, filed October 26, 2026, accession 0000020286-26-000059. The 90.9 percent quarterly property casualty combined ratio and the 88.2 percent year-earlier figure, the $663 million net income decrease and the components it names, net written premium growth, new business written premiums, and book value per share. Read October 27, 2026.