London insurance market companies earned total premiums of £49.206 billion in 2025, according to the International Underwriting Association's latest London Company Market Statistics Report, based on aggregated data from 80 member companies.
The total comprised £43.658 billion underwritten in London itself, plus a further £5.548 billion in "controlled business" overseen by London operations but written elsewhere, either internationally or in other parts of the UK.
The headline figure represents a slight decrease of 0.1% compared with the previous year, effectively flat income for the sector after 2024's £49.3 billion total, which itself marked a slowdown from the 10% growth recorded in 2023.
Property remains the largest class of business written in London, accounting for 29% of the market, more than twice the size of the next largest categories. Liability and marine each account for 14% of overall income.
Geographically, the UK and Ireland represent over half of total income written in London, with the US and Canada the most significant international market at around a quarter of premiums. Continental Europe plays a bigger role specifically in controlled business written outside London, accounting for a third of those premiums in 2025.
This year's report highlighted a genuine divergence between direct and facultative business and treaty reinsurance written in London.
Direct and facultative premiums totalled £32.338 billion in 2025, up 1.9% on 2024, while treaty reinsurance fell 6% to £11.270 billion, down from £11.985 billion the previous year. Treaty business now makes up just over a quarter (26%) of premiums written in London, with direct and facultative contracts making up the remaining 74%, proportions that are almost unchanged from the prior year despite the underlying divergence in growth rates.
Chris Jones, chief executive of the IUA, said the London Market has a strong reputation for the range of cover it offers, and that the report provides a unique and detailed insight into the insurance and reinsurance business transacted in 2025. He said this year's figures reflect challenging market conditions in many sectors, though areas of growth remain evident, pointing to direct and facultative premiums rising almost 2% even as treaty business declined, a fall he noted follows a 10% jump in treaty premiums the year before. He said many IUA members have emphasised the importance of risk selection and a disciplined underwriting approach in the current environment.
The 6% fall in London treaty premiums fits a pattern Insurance Business UK has tracked in detail across the global reinsurance market this year. Aon's Reinsurance Market Dynamics Midyear 2026 report put global reinsurance capital at a record $790 billion as of March 2026, with Gallagher Re describing property buyers as operating from the strongest negotiating position in more than a decade.
Guy Carpenter's global property catastrophe rate-on-line index was down 16% at midyear, an acceleration from the 12% drop recorded at the January renewals, and Swiss Re's own treaty pricing fell a further 4.6% in real terms at 2026 renewals even as the reinsurer renewed $19.5 billion of business.
That record capital and falling treaty pricing is the direct backdrop against which London's treaty book has contracted, while direct and facultative business, priced closer to underlying risk and less exposed to the capital-driven softening playing out at the reinsurance layer, kept growing.
This report lands amid a wider period of transition at the trade body itself. Insurance Business UK reported that the IUA has undertaken a rebrand alongside leadership changes since Jones took over as chief executive, part of a broader repositioning of the organisation's priorities around claims focus and market representation.
That same reporting noted the IUA represents 79 companies in the London insurance and reinsurance market, close to the 80 companies whose data underpins this latest statistics report.
The flat headline number obscures a genuinely different story once treaty and direct business are separated: London's direct and facultative business is still growing at a reasonably healthy clip even in a market participants describe as challenging, while treaty reinsurance is correcting in line with the same record-capital, rate-softening cycle playing out across the global reinsurance market this year.
For brokers and underwriters active in the London market, the practical takeaway is that "flat" premium income this year masks meaningfully different conditions depending on which side of that direct/treaty split a given business sits on, and the treaty softening shows little sign of reversing ahead of the January 2027 renewals.
