Progressive's Underwriting Is Only Half the Story. Higher Rates Power the Rest.

Progressive (NYSE: PGR) sells auto insurance. You have probably seen its ads. On the surface, that's the company's primary business. But it isn't the whole story. With interest rates looking likely to increase over the near term, investors are going to find the other half of the company's story, the float, increasingly interesting. Here's what you need to know.

Progressive does a good job of writing insurance

In the first quarter of 2026, Progressive's premium income was nearly $21 billion. It had a combined ratio of roughly 86%. The combined ratio measures how much an insurance company pays to operate its business and to cover claims, and compares that to the premiums it collects. A number below 100% indicates that the company is operating at a profit. Progressive is doing quite well on the insurance front.

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However, there's another part of the business that is vital to understand. An insurance company like Progressive collects premiums up front, but pays out claims later. In the meantime, it keeps the cash, which is known as the float. Progressive, like all insurers, invests the float. This is a very big piece of the business, with its investment portfolio sitting at $94 billion at the end of the first quarter. The company generated nearly $1 billion in investment income from the portfolio during the quarter.

Interest rates are a big deal for Progressive

Progressive is fairly conservative with its float. Roughly 95% of assets are invested in fixed-income securities. Interest rates play an important role in the income that the insurance company generates. With inflation running hot, the Federal Reserve just held interest rates steady. But the bias appears to favor rates rising in the near future. That will make Progressive's float an even more powerful income generator.

In the company's May performance update, it highlighted that the combined ratio was 82.1%, with net premiums earned up 10% from the same month of the previous year. So the insurance business continues to perform well. The next big leg up for the business will be the float's performance. And, if rates rise, the story could be very compelling.

Even if rates don't rise, Progressive is well-positioned. With nearly $1 billion in investment income from the float already, its strongly performing insurance operations will add to the float's size. So as long as interest rates don't fall, which seems unlikely in the current environment, Progressive's business is on very solid ground.

Reuben Gregg Brewer has no position in any of the stocks mentioned. The Motley Fool has positions in and recommends Progressive. The Motley Fool has a disclosure policy.