"We see it firsthand," said Tom Nally, president of TD Ameritrade Institutional, which serves as a custodian for independent registered investment advisors. "Something happens to an advisor, and the clients are left out in the cold."
Consider the numbers. The total number of financial advisors across distribution channels in the U.S. fell to 307,623 in 2012—down 4.4 percent since 2010 and 9.4 percent since 2004, when Cerulli began collecting data on the industry.
Read MoreAre you a stock or a bond?
The average age of advisors in the country is now 50.9 years, and 43 percent of advisors in the industry are over the age of 55 years, while just 11 percent are under the age of 35. Based on the expected number of retiring advisors, the entrance of new advisors to the industry and the growth in demand for financial advice, consulting firm Moss Adams has estimated that the industry could face a shortfall of more than 200,000 advisors by 2022.
While the industry as a whole faces a looming talent shortage, RIAs—particularly solo practitioners—are the most vulnerable. Most of them lack the resources to recruit and train young people and studies show that just 30 percent of them have any explicit succession plan in place.