Wealthy individuals who are planning to retire are uncertain about how much money they need to live on, according to a poll carried out by SEI, the US financial services and consultancy firm.

The survey of 31 wealth managers showed that 42 per cent of respondents said their clients' largest concern is uncertainty about their retirement goals. Some 61 per cent said their clients have a "number" in mind for retirement, but that it is not enough to achieve their goals.

The bank wealth managers surveyed said their clients also have concerns over their saving and spending levels during the retirement years - 26 per cent said saving levels were their clients' biggest concern. Some 16 per cent said spending levels were the biggest source of worry.

The poll also showed that recent deterioration in economic conditions had affected the views of private banking clients towards investing, with 42 per cent of wealth managers saying their clients were "extremely" concerned about downside risk.

"It's quite clear from these survey findings that investors have a difficult time identifying what their retirement is going to look like and how they're going to pay for it," said David Campbell, senior vice president for SEI's Private Banking Group.

SEI polled wealth managers who attended a recent series of seminars in the US.