Platform assets under administration fell more than 4% in Q3, according to figures from consultancy group The Platforum, which suggested advisers have begun to doubt the value of platforms to their business.
Including figures from the new Sippcentre proposition for the first time, UK retail adviser platform assets were £164bn at 30 September 2011, a decline of 4.3% for the quarter, The Platforum said.
Managing director Holly Mackay (pictured) said regulatory uncertainty and market turmoil had, as expected, hampered growth, but also pointed to a surprise third factor.
She said doubts over the value platforms offer adviser businesses are also now posing a challenge to the market.
"Typically advisers complain about the cost but I think there is more of a focus now on value," she said.
"The bigger question is not just what platforms charge but what are adviser firms collectively paying platforms each year and I am starting to hear more rumbles from people suggesting it should not be a basis point discussion but a service fee discussion."
Mackay said she had a sense advisers feel "a bit let down" by some offerings and argued platforms need to provide "watertight" administration services to justify their charges.
She added lots of IFAs continue to use adviser software - rather than platforms - as the cornerstone of their businesses and said a number of factors are putting a brake on the market's growth.
But she said while platform investment was "slowing a little", the figures should be viewed in the context of wider market volatility.
"Against a market backdrop of a 14% fall in the FTSE, this is not a bad result - but neither is it the stellar growth we witnessed back in 2009, 2009 and 2010."
Gross sales were slightly flatter than last year across the board, with the exception of Cofunds which managed to generate £4.6bn in sales.
Despite the gloomy quarter, Mackay thinks the fall in assets is just a blip and predicted momentum will pick up in the first half of 2013 as platforms show the value they can add in an adviser charging environment.
"Platforms will see out this race - they're just having a little breather, taking on some water and re-focussing on the basics including core administration, service and price."
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