Consultant MDRC surveyed banks in the UK and found that private banks are responsible for less than 30 per cent of total wealth of more than Â£500 billion, with the rest of the market shared between independent financial advisors and investment managers.
The company stated: "Despite the introduction of a wider range of wealth management products, high net-worth individuals remain largely disappointed with products and services available from the major wealth management firms."
As the amount of money held by wealthy individuals in Britain grows, MDRC is urging private banks to specialise and meet the changing needs of potential customers, in a similar way to companies like Credit Suisse and UBS, Reuters reports.
UK private bank Barclays purchased wealth management firm Gerrard in 2003, while Royal Bank of Scotland has its Coutts Group and Adam & Company subsidiaries.
Another poll of nearly 600 wealthy individuals in France, Germany and the UK found that low market penetration in Britain was blamed on poor branding and low levels of service, with UK customers least satisfied with their bank.