Mary Lacey Gibson, a financial planner and small-business coach for the Garrett Planning Network based in San Juan Batista, Calif., recalls a young man who came to her for guidance. At the age of 24, he was making $90,000 a month from a few websites he had created. "He had a motorcycle and a backpack and wanted to just travel from place to place until he was 30," she said. But he also wanted to save for retirement. "So we set him up with a relatively simple plan and let it go. He was very bright."
Gibson's young client was indeed smart to prepare for the future—but it helped that he had plenty of cash to put aside. Diverting money to a retirement plan isn't always so easy to do if you work for yourself, unlike traditional wage earners whose contributions are automatically deducted from the paycheck. "For most of us who are working stiffs, the plan is handed to us," said Ric Edelman, chairman and CEO of Edelman Financial. But those who are their own employer? "They tend not to create a retirement plan in the first place."
A recent TD Ameritrade survey found that 40 percent of self-employed individuals weren't saving regularly for retirement, and 28 percent weren't saving at all. That's compared to 12 and 10 percent, respectively, of the traditionally employed.
A survey by American Express of small-business owners last year came up with similarly dispiriting results: 60 percent of respondents said they were not saving enough for their so-called golden years.
It's an alarming situation, given the expanding ranks of the self-employed. From 2001 to 2012, self-employment in the U.S. grew by 14.4 percent to a total of 10.6 million jobs and 7.1 percent of the total workforce, according to an Economic Modeling Specialists International report. (It excluded entrepreneurs who'd incorporated their businesses.)
(Read more: Planning for your retirement: Making your money last)