Aon has announced a collaboration with national financial planning firm Wren Sterling that will enable the two businesses to refer clients to each other, in a move that reflects the growing convergence between insurance broking and wealth management in the UK.
Under the arrangement, Wren Sterling will refer clients requiring risk management and insurance advice to Aon, while Aon will introduce private clients and small and medium-sized enterprises (SMEs) with up to 25 employees to Wren Sterling for financial planning support. Services covered include pensions, investments, inheritance tax and estate planning, employee benefits, and workplace wellbeing.
The partnership brings together two businesses that have each been expanding rapidly.
Aon operates in more than 120 countries and reported total revenues of $15.7 billion for the first nine months of 2024. Meanwhile, Wren Sterling, backed by US private equity firm Lightyear Capital and headquartered in Nottingham, advises on more than £12.5 billion in client assets across 13 UK offices. The firm added £1.8 billion in acquired assets under management during 2025 alone as part of an active buy-and-build strategy.
Wren Sterling's client base is predominantly high net worth, a profile that aligns closely with the specialist insurance lines Aon brings to the collaboration.
Paul Chafer, chief commercial officer at Wren Sterling, said: "Wren Sterling has a growing high net worth client base that will benefit from Aon's specialist insurance lines, while our Workplace business is increasingly multi-national, so Aon's global presence strengthens our proposition significantly. For Aon's clients, our national presence, proven ability to work with clients akin to them, and focus on relationships over solutions, will offer the level of personal service and outcomes they are used to receiving."
The partnership arrives at a particularly consequential moment in the high net worth market.
The UK's 2024 Autumn Budget introduced sweeping changes to the inheritance tax treatment of pensions, with unused pension funds and death benefits set to be brought within the deceased's estate for IHT purposes from April 6, 2027.
That dynamic is already driving demand. New business sales in the high-net-worth international life insurance sector reached £41.3 billion in 2024, a 25% increase on the previous year, driven in part by strong UK demand following changes to the tax regime, with annual sales projected to rise to £67 billion by 2030. According to research, a key trend in 2025 has been the growing use of life insurance as a strategic tool in tax and estate planning, with advisers leveraging it as a vehicle within broader wealth transfer strategies.
The UK high net worth household insurance market nonetheless remains challenging, with insurers showing a reduced appetite for complex risks and the ABI recording more than £4 billion in property claims up to Q3 2024, the largest amount on record. Specialist cover for fine art, high-value property, and personal collections continues to require bespoke underwriting, reinforcing the case for dedicated private client expertise.
The inclusion of SMEs in the partnership is equally significant. The referral arrangement covers businesses with up to 25 employees, a segment that is chronically underserved on both the insurance and financial planning fronts.
Hiscox's 2025 Global Protection Gap Report found that 74% of UK SMEs have some level of underinsurance, with 22% lacking core covers such as professional indemnity, public liability, property, and employers' liability. Meanwhile, only 14.5% of UK SMEs said they were very concerned about being underinsured in GlobalData's 2025 UK SME Insurance Survey, making it the lowest-ranked issue out of 23 risks assessed, suggesting that underinsurance is often driven by a lack of awareness rather than deliberate cost-cutting.
Alexa Owen (pictured), head of private clients in the UK for Aon, highlighted the importance of catering to their clients' needs and connecting them with a trusted resource.
"[I]t is imperative that private clients and SMEs adequately protect their assets and manage their risk and compliance. Our shared values ensure that clients of both Aon and Wren Sterling will benefit from this collaboration," said Owen.
