“You really improve your retirement prospects by working longer,” says Steven Sass, program director of the Financial Security Project at the Center for Retirement Research. “If you retire at 70, your monthly benefit is at least 76 percent higher. It's a crime nobody knows that.”

For him the ideal retirement age would be 67 or 68, when a retiree could live on other savings while waiting the two to three years for the maximum payout.

Other factors have been pushing the retirement age upward, as well. That includes the disappearance of defined benefit pensions, which guaranteed retired workers income for life, as well as a healthier population that is generally living decades beyond age 65.

“Today's grandparents aren't sitting on the front porch pouring lemonade and watching the grandkids,” says Pam Dumonceau, the owner of Consistent Values Inc., a registered investment advisory firm in Greenwood Village, Colo.“They're going skiing with them or to the Grand Canyon. They're far more active than their parents.”

Greater education also has played a big part in delaying retirement, according to the CRR. More of the baby boomer generation attended college than any previous generation. This relieved them of the manual labor that often sidelined their parents, but their skills often keep them in demand longer—or wanting to work longer at jobs they enjoy.

“They stay there because make more money and are more productive,” Sass says.

Nonetheless, 65 is still the age employees set their sites on primarily because that's when Medicare kicks in.

“I frequently work with baby boomers who would have retired in their early 60s if they were eligible for Medicare,” says Larry Luxenberg, a financial advisor in New City, N.Y.

Nonetheless, there are so many ways and means to retirement that many think there is no set retirement age anymore. That's at least the viewpoint of Laura Gilman, president of LGA Financial inLos Angeles. “People think it's 65, but some people work into their 90s. It all depends on where employees are in their career, whether they like their job and their happiness level. There's no longer one age.”

For example, some employees are targeting a specific pension for their retirement date.

“I have a client, a judge who doesn't get full job-related benefits until she's 70,” says Ken Waltzer of Kenfield Capital Strategies in Los Angeles.

Many clients find themselves wanting to down shift in their 60s, and so are creating a semi-retirement, Dumonceau says. Often companies will be flexible with hours and benefits to keep experienced workers. Dumonceau says she had a client who was working in health care and wanted to work part-time to help with her cash flow.

“She was sure they wouldn't do part-time, so we put together a retirement plan for her,” Dumonceau says.

But when the client went in to retire, the firm asked her if she would stay on part-time. In this way, many advisors report that their clients see retirement as a transition rather than a deadline.

“They're not jumping off the cliff but rolling down the hill to retirement,” says Barry Glassman, of Glassman Wealth Services in McLean, Va.

Another reason people are working longer is because the crash of 2008 left many people gun-shy, says Ken Waltzer of Kenfield Capital Strategies in LA.

“Many people who retired then got a rude awakening and went back to work because they won't have enough money,” Waltzer says.

The dream of retiring in their 50s is far less common now, he adds. They wait longer because fears of the bear market cause them to believe they can afford to retire anytime soon.           

Other woes delaying retirement indefinitely is the need for many boomers to care for their parents and their children who may be saddled with college debt and poor job prospects.

“The retirement age has moved back because of rising health care costs, rising living expenses, and new factors such as kids still on the payroll,” says Taylor Gang, a financial planner at Evensky & Katz in Coral Gables, Fla. “Boomers have to take care of elderly parents, too. That can be a game changer.”

Gang deems a client's retirement age to be their moment of financial independence.

“It's based on your spending and your net need,” Gang says. For example, financial independence is achieved when a client who spends $100,000 a year, gets $30,000 from social security and produces more than $70,000 [from savings or some other source] annually with ease.

His firm uses the “bucket method” where cash is meted out over a safe time horizon to keep clients going.

“The bucket method has two advantages: we harvest cash returns opportunistically so we're selling high and buying low,” he says. And clients are less focused on the managed portfolio and potentially scary market returns.

The bucket is implemented in reality about a year to two years ahead of when clients actually retire. If a couple makes $100,000 but only spends $85,000, the balance is redirected to the buckets.

Of course, clients' biggest fear “is running out of money,” Waltzer says. “When I do the planning, I try to create a fairly high success rate and use a longer life span than most people.”

For example, not too long ago Waltzer drafted a plan for a 33-year-old, but extended his life span to 105. This might not be unrealistic given the pace of medical development and the health consciousness of younger clients. But to Waltzer, the extended age was one way to create a cushion. He also works out plans that have a 90 percent “Monte Carlosuccess rate.”

The bottom line, experts say, is that a lot of the old retirement rules don't apply. The situations vary as much as the clients. Like other advisors, though, Luxenberg finds clients are always far more surprised that they have enough to retire than that they have too little.

“Two spouses with modest pensions can be making $150,000 in retirement,” he says.

Illustration by David Senior