Under 34s stand to inherit only half as much as their parents, according to a report by HSBC which points to a growing demand for advice on how to stop wealth being eroded before it can be passed on.
A survey of 2000 adults in HSBC's Age of Inheritance found £1.1trn may be left to beneficiaries by 2047, compared to £194bn by 2015.
However by 2062 this will have fallen to £552bn, as inheritances are eroded by the rising cost of living and life expectancy.
Increased longevity means the baby-boom generation are retaining their wealth, according to the report, and there are far lower expectations of how much the recipients of this inheritance will pass on to future generations.
Those in the 45-54 age group expect to inherit an average of £108,384 - and nearly half surveyed had already done so. But people aged 16-24 only expect to inherit an average of £45,662.
David Wells, head of investments, pensions and savings at HSBC, said the findings of the report serves to highlight the importance of financial planning both for those who plan to bequeath an inheritance and for those who are likely to be in receipt of one.
"Wealth needs to be carefully managed so that the value is not eroded before it can be passed down to future generations," he said.
Over half of 45-54 year olds planned to spend at least part of their inheritance on luxuries (23%) or the holiday of a lifetime (34%). Over 55s plan to spend 61% of their inheritance, compared to 52% of under 34s.
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