The average minimum investable amount set by advisers for their clients is almost £50,000, according to a poll of more than 200 practitioners.
Prospective customers need at least £48,487 in investable assets to receive bespoke advice, according to the Yorkshire Building Society, which also found that almost half of UK consumers have less than £10,000 to invest.
The findings come from online interviews with 211 advisers and 2,169 adults in September.
The minimum investment amount cited by advisers echoes sentiments from other providers. A Defaqto report published last year concluded that, among the main high street banks, some defined their 'sweet spot' customers as those with a minimum of £50,000 or £100,000 in savings and investments.
However, a report out earlier this month from Aviva suggested as much as 46% of advisers are continuing to work with clients with investable assets of less than £50,000.
Of the adviser participants in the Yorkshire Building Society survey, some 91% warned of a growing financial advice gap in the UK, with 45% of those blaming the introduction of the Retail Distribution Review and 23% pinning the blame on the withdrawal from advice of a number of high street banks.
Moreover, those advisers polled said they expected the situation to worsen - 53% expect to have to stop advising some clients as their accounts are no longer commercially viable.
From a consumer perspective, more than one in four (27%) savers looking for financial advice are finding it 'difficult' or 'very difficult' to find help, despite having an average £240 a month to save or invest, according to the poll.
Half of those said they believed their savings and investments were too small to interest financial advisers, while one in five blamed the withdrawal of financial advice services on the high street and financial advisers closing businesses.
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