Denny Jensen, 70, retired from his job as a senior vice president of Visa International in 2004 and spent the next several years playing golf. He eventually got bored and decided to buy a franchise, because the idea of a proven company that provided plenty of support appealed to him.
In January, he combined retirement savings with a personal loan and invested $220,000 for a Molly Maid franchise in the Reno, Nev., area.
"I enjoy getting up in the morning and going to work," Jensen said. "Your mind is working all the time, whether dealing with a customer complaint" or brainstorming about marketing. He expects to turn a $100,000 profit this year.
Jensen represents a growing trend among older Americans. Instead of a fresh-faced teenager or middle-aged manager, a retiree might greet you behind the counter when you request a cleaning service or place your order for a Papa John's Pizza.
Older Americans are becoming a fast-growing segment of those buying franchises. The percentage of people 55 and over who are franchise owners has risen from 20 percent in 2007 to 28 percent—a 40 percent increase, according to Franchise Business Review. Such operations satisfy the desire to run a business but provide an established community, making it easier than starting from scratch.
"It's almost like buying a business in a box," said Jody Holtzman, senior vice president for thought leadership at AARP. "You're jumping into something new," but it has an established brand, and marketing, distribution and supply chain.
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Older Americans want to "control their own destiny and go into business for themselves but not by themselves," said Matt Haller, a spokeman for the International Franchise Association. "They see franchising as a great way to do that." At the International Franchise Expo in New York in June, an event that attracts 18,000 prospective franchisees, 28 percent of attendees were 51 and older.
Older people also have a key advantage that makes ownership easier to achieve than it is for many younger people: access to capital, either in cash savings or a 401(k).
The senior franchise story isn't just about affluence and an overly easy retirement, though.
Adam Sohn, vice president of brand alliances and partnerships for AARP, said a big driver of the boom is what he called the "working worried": older people who fear being pushed out of their jobs, as many who are unemployed and finding it difficult to get back into the job market.
The franchise model makes sense for seniors with entrepreneurial flair but no grounding in today's app economy—people who aren't interested in "coming up with the next Facebook," Sohn said.
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Franchisors with older customers are particularly welcoming of senior buyers.
Joe Smith, vice president of franchise development for Papa John's International, said his company is attracting young retirees with business experience and said older owners are comfortable investing more in ensuring that the store well launched.
Les Clark, 72, owns two Papa John's in The Villages, a Florida retirement community. His biggest concern was whether the area would support a pizza place, more often associated with teenagers and young families. The answer was yes.
"So many people thanked us for bringing Papa John's to The Villages," he said.
Jania Bailey, president and chief operating officer of FranNet, which matches potential franchisees with franchisors, said 70 percent to 80 percent of her clients are over 50. They are typically outplaced or soon-to-be outplaced executives with significant savings looking to replace a six-figure income.
Franchises are considered a safer bet, and there's some data to back that up. A 2012 study by her group found that after five years, 85 percent of her franchisee clients remained in business, compared with 50 percent who started their own thing.
Seniors are also moving beyond traditional fast-food franchises to service-based businesses that require less up-front investment but are profitable longer term.
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Take Tom Roskosz, 64, who spent $150,000 on a Fish Window Cleaning franchise in Savannah, Ga.
"I would never have dreamed of window cleaning," he said, but he liked not having to work nights, weekends or holidays.
Roskosz now has 700 regular customers and projected revenues in the $250,000 range this year. "I love meeting the people and the business owners," he said. "I enjoy the challenge that comes with building up your revenue and relationships."
Ellen Sullivan, 55, leveraged her background as a nurse to Doctors Express, a franchise that provides urgent care services.
She and her partner, a friend who is a doctor, paid $750,000 in start-up costs and opened in October 2010. It was a great choice for this stage of her life and helped fuel her passion for providing affordable health care, she said.
"Every day we're making a difference in people's lives," said Sullivan, who lives in Jacksonville, Ga. "It's very rewarding to hear they're very satisfied with the services they receive."
Jensen recently received approval from Molly Maid to expand his territory into Carson City, Nev. Though he may eventually hire a full-time manager, he said, "I don't have a vision of selling it."
—Julie Halpert, Special to CNBC.com