The casualty insurance-linked securities market (ILS) has experienced considerable momentum throughout 2025, with several transactions occurring in the latter half of the year, and according to Willis Re, the market is on a trajectory of potential exponential growth.
The firm noted that the casualty ILS market size at any point in time is particularly hard to estimate, due to the fact that many deals stay private and many-whole account ILS sidecars sometimes include a large casualty element.
“However, based on public disclosures the casualty ILS market has probably already exceeded $5 billion, up from less than one billion in 2022,” Willis Re said.
Recent deal flow within the casualty ILS space has been moving at a steady pace.
“We have seen the launch of multiple reinsurance sidecar syndicates at Lloyd’s, established to assume a share of the sponsoring carriers’ outwards cessions. The details vary, but a proportion at least of the risks ceded to the sidecars’ ILS backers will be of the long-tailed variety,” Willis Re noted.
Earlier in the year MultiStrat, the specialist underwriter, reinsurance investment facilitator and casualty ILS firm launched two funds on the scale of $100s of millions.
While in July, Ascot Group and Antares Capital partnered together to set up Wayfare Re, a $500 million sidecar for Ascot’s casualty book.
Together these initiatives alone have added more than $1 billion to the casualty ILS sector in the second half of 2025, Willis Re noted.
As a reminder, you can find details of numerous reinsurance sidecar investments and transactions in our directory of collateralized and funded reinsurance sidecars transactions.
Meanwhile, Ledger Investing, the insurance technology (insurtech) and casualty ILS specialist, recently launched Korra, a separate SaaS platform that the company says it has used to structure, execute and service upwards of 170 casualty ILS deals, which are worth around $2.5 billion.
Concurrently, Willis Re also said that another way to bring ILS capital to the casualty market is through a dedicated fund which underwrites specific reinsurance contracts through a fronting reinsurer.
“Both types of structure tend to be backed by savvy investment funds attracted by returns which may run higher than 20%. That is the boost that supports the claim that casualty ILS is uncorrelated with other financial instruments, and particularly that it acts as a balance for nat cat securities,” the firm explained.
Willis Re also acknowledged that Lloyd’s of London’s ILS structure London Bridge 2 PCC, has also been a key promoter of casualty reinsurance ILS sidecars in Lloyd’s, which has helped grow the casualty ILS considerably in recent years.
Furthermore, the company also emphasised that legacy reinsurers are a major contributor towards the recent growth that’s been seen within the casualty ILS space too.
In August, we reported that Enstar, one of the largest legacy and run-off reinsurance specialists in the world, had launched its first direct third-party capital play, a $300 million casualty reinsurance sidecar named Scaur Hill Re Ltd.
The sidecar extends the firm’s available run-off capital, and also provides ILS investors with an optional, pre-priced exit after seven years, and a mandatory close after ten.
To conclude, Willis Re acknowledges that the casualty ILS market still remains a relatively new sector, noting that the claims it has accepted so far have not yet entirely matured.
“It therefore remains untested. That said, risk carriers with a very strong casualty reserving history and the talent to price liabilities with confidence are likely to gain investors’ confidence. Those able to deliver evidence of such experience and expertise can benefit from an array of products.
“Technology-enabled actuaries working hand-in-hand with capital markets teams and reinsurance experts are powerfully equipped to help cedants design and structure solutions that match all the counterparties’ goals and appetites.
“As the casualty ILS market accelerates along a potentially exponential growth path, now is the time to consider how best to take advantage,” Willis Re concluded.
