In the last few years, financial advisor Ron Carson has observed prospective clients increasingly asking whether his firm has a succession plan in place. Luckily, he does, and he is happy to describe it to them.
"I tell them, 'If you are interviewing other firms, ask them to give you the same [information] we can share with you that assures you there will be no disruption in service,'" said Carson, a certified financial planner and the founder and CEO of Carson Wealth Management Group.
What the question tells him is that it's becoming more important to investors to know what will happen to their assets if their financial advisor unexpectedly dies or is disabled. And, thus, a succession plan can serve as an appealing aspect of a firm.
And yet, study after study shows that roughly two-thirds of advisory businesses have no succession plan at all. Carson, who also does consulting work with advisors through another business he created, Peak Advisor Alliance, estimates that just 5 percent actually have a well-thought-out, detailed plan.
Read MoreGood advisors have marketing plans
Among other things, succession planning "has to be addressed from an income-tax, transfer-tax and estate-planning standpoint. There has to be a mechanism to keep [the firm's] stakeholders in place, and there has to be communication with existing clients," Carson said.
He considers a succession plan different from a continuity plan, which only addresses an advisor's tidy, planned retirement. It's the unexpected events that advisors need to prepare for, he said.
In a recent CNBC.com poll, 91 percent of respondents said it's important for advisors to have a succession plan. So the question is, Why do so few have one?
"It happens for the same reason people don't buy life insurance or get annual physicals: It involves discussing uncomfortable areas," said Mark Tibergien, CEO of Pershing Advisor Solutions. "Part of it is fear, a bigger part is inertia, and a third part is … never quite getting around to figuring out who the ideal [succession] partner is."
Read MoreA digital strategy for your firm
Financial advisors might soon have no choice but to get serious about succession planning. The Securities and Exchange Commission plans to release a rule proposal this fall that would "require investment advisors to create transition plans to prepare for a major disruption in their business," SEC Chairman Mary Jo White said in a recent speech.
While it would be yet another regulatory requirement for advisors overseen by the SEC, some industry watchers say it's a needed one.
"The No. 1 reason that advisors need to have a plan in place is this: If you have a fiduciary responsibility to your clients, you need to ensure that their financial affairs are attended to the moment you are not able to," Tibergien said.
Carson of Carson Wealth Management Group, for one, has gone to the proverbial "nth degree" in creating a plan. In addition to legal documents ensuring a smooth transition, he has created what he calls a death video.
In it he tells clients that if they are watching it, it means he has died. And he tells them, in detail, exactly what is happening at his firm in his absence and why there will be no disruption in client services.
"It's reassuring," Carson said. "I'm letting them know the plans. It's just memorialized in a video."
Also, through Peak Advisor Alliance, he offers an exercise that involves financial advisors writing their own eulogy. Then the advisor is faced with a coffin and asked to lie in it to get a taste of the reality of death.
Carson estimates that fewer than 50 advisors have agreed to climb into the coffin and lie there with their eyes closed while listening to soft music and a reading of their self-written eulogy.
Read MoreAdvisors take on cybercompetitors
"Those that go through the coffin thing see the end for a moment, and it drives them to live their lives by design, not by default, and succession planning is part of that," Carson said.
Financial advisor Greg Hammond got into the coffin about eight years ago.
"It made an impact," said Hammond, a CFP and president of Hammond Iles Wealth Advisors. "It's important to think beyond [clients'] finances.
"We wanted to make a greater impact not only in our own lives but in our firm, too," he said.
Hammond and his business partner have a plan in place. They also are in negotiations with other advisors who would be interested in using Hammond's firm as a succession partner to protect the value of their practices, both for their loved ones and their clients.
Carson is passionate about the need for succession planning. And he has seen repeatedly what happens when a firm's owner dies with no plan in place.
"There's a crisis of confidence among employees and clients," he said. "With no succession plan, within six months clients and employees will be gone."
A Pershing study released in early 2013 said that almost 1 in 5 independent firm owners would exit the business by the end of 2019. If they have no succession plan, say some industry watchers, they are doing clients a disservice.
"Many of those clients are probably the same age as the advisor, and if they are looking for their teeth and glasses, they don't want to be looking for another advisor," said Tibergien at Pershing Advisor Solutions.
Read MoreAdvisors add insurance to menus
Not only does a plan protect clients, it also ensures that the hard work advisors have put into building their practices won't just disappear.
"I think many of us let our lives unfold without thinking about … how we want to be remembered," Hammond said. "You don't want to work for 30 years, working for clients, and then just have your firm dissipate.
"I think it's important that we think about that."
—By Sarah O'Brien, special to CNBC.com