RIA growth is showing no signs of slowing down.

Nearly 16,000 RIA firms are managing $2.4 trillion in assets, according to Cerulli Associates. The research firm also forecasts that RIA and dually registered channels will grow their combined asset marketshare 40% by 2018.

“As of year-end 2013, the RIA and dually registered segment account for 20% of total intermediated retail investor assets, and we expect that number to reach 28% by 2018,” states Kenton Shirk, associate director at Cerulli.

Currently, Schwab and Fidelity find themselves at the top of the RIA industry, Cerulli reports, with the two firms accounting for more than $809 billion in RIA mutual fund assets.

The firm's research notes that RIA growth is being driven by "the combination of projected advisor migration patterns and investor preferences, especially among high-net-worth investors."

Such growth reflects a general trend in wealth management that favors the RIA model, says Alois Pirker, research director at Boston-based consulting firm Aite Group.

"There is a shift from transaction-based brokerages to fee-based advisors, but that is not just concentrated on RIAs," Pirker says. “When you look within wirehouse firms, their fee-based platforms are growing at similar rates. Anybody in the market who has spent effort developing fee-based platforms is benefitting.”

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