Aon’s cat bond issuance business expanded more than 50% in 2025: CEO Case

While the overall catastrophe bond market saw issuance rising around 40% year-on-year in 2025, broking group Aon saw its activity supporting issuance of new cat bonds rising by more than 50%, CEO Greg Case said today.

In the fourth-quarter of 2025, Aon reported growth in revenues related to its insurance-linked securities (ILS) business in the double-digits, outpacing its overall reinsurance divisions’ 8% organic revenue expansion in the period.

Speaking during the Q4 earnings call just now, Aon CEO Greg Case provided some additional colour and said his firm saw the cat bond business it acts on growing faster than the overall catastrophe bond market.

In his opening remarks Case explained, “We help clients access alternative forms of capital through cat bonds, which may include parametric triggers, where market issuance rose more than 40% in 2025 and Aon’s issuance increased more than 50%.”

Edmund Reese, CFO of Aon went into additional detail, saying, “Insurance-linked securities benefited from record cat bond issuances, which reached $59 billion outstanding as investors increasingly seek uncorrelated asset classes. STG also saw elevated demand for our analytics, which help clients access alternative forms of capital.

“Reinsurance delivered 8% growth driven by double-digit growth in both insurance-linked securities and our Strategy and Technology Group (STG), as well as continued strength in facultative placements.”

Acknowledging that the softening reinsurance market provides a headwind to revenues in the broking units that operate in that space, Reese’s comments implied that cat bond and ILS activity is expected to help counteract any decline in traditional reinsurance.

“Even with this market headwind, we continue to expect full-year 2026 organic revenue growth in-line with our mid-single digit or greater objective, supported by higher limits, ongoing strength in international facultative placements, record activity in insurance-linked securities and growing demand for STG analytics,” Reese explained.

Adding that, “We are uniquely positioned at the intersection of insurance and capital markets, helping clients access alternative capital at scale.

“This positioning becomes even more valuable in a softer rate environment, where innovation matters as much as price.”

Capital markets activity, under the brokers’ Aon Securities unit that specialises in investment banking services and insurance-linked securities, has been increasing in recent years, with Aon seemingly growing its share slightly over the last year or so.

As of the middle of 2025, our Artemis leaderboard of catastrophe bond banks and brokers showed Aon Securities as having worked on just under $27 billion of outstanding cat bond deals.

Now, that leaderboard chart shows Aon Securities with just over $30 billion of outstanding cat bond deals it has worked on.

At the mid-point of 2025 the leaderboard figure accounted for around 48% of the outstanding market, but that percentage share has now increased to around 50% of the current outstanding catastrophe bond market, which we size at around $59.89 billion at this time.

Of course, that’s based on deal sizes and volume of dollar issuance, not number of transactions.

However, at the mid-year our cat bond broker leaderboard showed Aon Securities as having worked on 92 of the outstanding catastrophe bond deal’s we’d tracked at that time, with a sole role as structurer or bookrunner on at least 64 of them.

Now, our leaderboard shows Aon Securities as having worked on 102 outstanding deals, with at least 73 of them involving a role as a sole or lead structuring agent or bookrunner.

As you’d expect, the majority of other brokers and banks that remain among the more active, have also grown their numbers meaningfully as well, given the significant catastrophe bond market expansion witnessed in 2025.

The growth in the catastrophe bond market is driving higher investment banking revenues for all the major broking houses, a trend likely to continue through 2026 if issuance remains at historically elevated levels as many expect it will.

The leaderboard has also become more concentrated at the top to those with a reinsurance operation (Aon Securities, GC Securities, Swiss Re Capital Markets, Howden Capital Markets & Advisory), rather than pure investment banks.

Add in the expanding newer areas of the ILS market such as casualty sidecars and it’s clear the investment banking units of the brokers are becoming increasingly important business units for their parent companies.