Gallagher completes major $12.45bn acquisition

Gallagher has completed its $12.45bn acquisition of AssuredPartners.

The transaction was announced in December 2024, with Gallagher making the swoop to scale its UK and Ireland arm and expand its retail middle-market property and casualty offerings across the US.

The deal was closed today (18 August 2025). It means that close to 1,000 colleagues have joined Gallagher in the UK and Ireland, as well as 900,000 new clients.

In addition, Harman Kemp, Romero Insurance Brokers and CIA Insurance Services, which are all UK-based firms owned by AssuredPartners, join Gallagher.

In Ireland, meanwhile, AssuredPartners businesses Gallivan Murphy Insurance Brokers, O’Callaghan Insurances and CFM Group will also join Gallagher.

The majority of teams and brands will integrate into Gallagher’s UK and Ireland retail division, with some colleagues and specialisms becoming part of its London market specialty operations.

“I am extremely excited to welcome our new colleagues to Gallagher,” said J. Patrick Gallagher, chairman and chief executive.

“Together, we will further build upon our client-centric, entrepreneurial cultures and utilise our product and industry expertise, extensive data, innovative analytical tools, outstanding service and broad product offerings to provide our clients with the very best insurance and risk management solutions.

“I am confident the combination will deliver tremendous value to our clients and our shareholders.”

Ripple effect

Following the deal being announced last year, Mike Latham, chief executive at family owned broker Verlingue UK, felt the move could instigate an M&A ripple effect, where rival firms Marsh and Aon “ramp up” acquisition activity in response to the deal.

He said: “It’s all adding up. The purchase of AssuredPartners by Gallagher is mind blowing. That means that Marsh will probably ramp up [its] acquisition strategy, it probably means that Aon will also ramp up [its] acquisition strategy – even though [it has] just agreed the deal with Griffiths and Armour [in November 2024].

“I just think [the market is] going to end up with a smaller number of players of any significant size to be able to provide the clients with adequate choice.”