The 10 largest professional trustee firms in the UK oversaw 45 per cent of the defined benefit (DB) pension scheme market in 2025, a share projected to rise to two-thirds (66 per cent) within the next five years, according to a survey by Isio.

The sixth edition of its Professional Independent Trustee Survey found that these firms oversaw 2,400 pension schemes, representing 45 per cent of the market (up from 31 per cent in 2020), with a combined asset value exceeding £1trn.

Over the past six years, Isio interviewed the UK’s largest professional independent trustee firms to gain an understanding of market behaviour and emerging trends.

Its 2026 survey showed that demand for professional trusteeship remained high, with expectations of further growth as governance standards continued to rise and regulatory scrutiny caused schemes to access greater specialist support.

In the research, professional trustee firms also reported significantly higher workloads across existing schemes, driven by governance requirements, data remediation and preparations for risk transfer.

This supported average revenue growth of 12 per cent over the year, despite little change in total appointments, and highlighted how demand was being fuelled more by complexity and project activity than by an increase in scheme numbers.

Meanwhile, the survey found that sole trusteeship accounted for more than half of all appointments (55 per cent) and is projected to reach around 65 per cent within the next five years.

Isio director, Harvi Rana, explained that professional trustees were playing an increasingly important role as governance expectations evolved.

“As schemes progress towards endgame and navigate a more complex regulatory environment, there is a clear need for robust oversight and specialist expertise,” Rani said.

“What we are seeing is a shift in how demand is developing. Growth is no longer being driven simply by an increase in the number of schemes, but by the complexity of the work required to manage them effectively.

"This is reinforcing the role of professional trustees in helping schemes make well-informed decisions at critical stages in their journey.”

Raini added: “As a result, the largest firms are overseeing a growing share of the market, reflecting the value placed on experience, scale and governance capability in today’s pensions landscape.”

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