The 10 largest professional trustee firms now sit on more than 2,400 UK pension schemes as of 2024, up from 2,300 a year earlier, including 43% of defined benefit schemes, new research suggests. It projects they could control two-thirds of the defined benefit market within the next five years.  

Isio's 2025 Professional Independent Trustee Survey echoes views expressed by the chief executive of the Pensions Regulator, Nausicaa Delfas, when she announced a tighter regulatory grip on professional trustees earlier this month. 
   

   

Isio agrees with TPR that about £1tn in pension assets is handled by large professional trustee firms, and that sole trusteeship is a key driver of growth. Sole trustee hires accounted for nearly half (48%) of all appointments last year, up from 41% in 2020, and Isio projects that corporate sole trustee roles could represent almost 70% of all appointments in the next five years. The largest scheme under sole trusteeship is currently £3.4bn in size. 

The consultancy expects the reach of trustee firms will continue to grow. It projects they could manage two-thirds of the DB market within the next five years.  

“As DB schemes mature and reach critical phases in their individual journeys and endgame planning, the involvement of a professional trustee is clearly proving instrumental to securing the best possible future for these schemes,” said Isio director Harvi Rana.
 
“The influence of professional trustees will continue to grow, and the Regulator’s intentions to introduce a new oversight framework reflects the increasingly key role they will play in safeguarding and securing the future of DB schemes,” Rana added. 

The 10 largest firms saw a year-on-year increase in trustee directors from 320 in 2023 to 350 in 2024, according to Isio, while average revenue was up 15%, in a fifth consecutive year of double-digit growth.  

However, seven mid-tier firms are actively competing for appointments, Isio says, holding about 200 appointments between them and managing £13bn in assets.  

Professional trustees have increased the representation of people with protected characteristics in the trustee world. Nearly half (44%) of trustee directors at the 10 largest firms are women, compared with just a quarter (24%) in the wider trustee market, Isio found.  

Representation of ethnic minorities is slower to improve; according to the survey, just 8% of trustee directors at the 10 largest firms come from ethnic minority backgrounds, stagnating at 7% between 2020 and 2023, only slightly above the 5% in the wider sector.