The average cost of retirement is more than $700,000 or about two-and-a-half times that of the average house and nine times more than the average cost of a college education.

By comparison, the average cost of a home is $278,300, the cost of a college education is $83,400, and the cost of raising a child to age 18 is $245,300.

Despite retirement's hefty price tag, the report finds that 81% of Americans don't know how much they'll need to fund their retirement. In addition, a growing number of younger generations think they'll need to personally fund a larger portion of their retirement and therefore expect to rely less on their employers or the government.

“That three-legged stool for funding retirement – that being Social Security, employer pensions and personal savings – is becoming wobbly at best for most people,” Sabbia said.

According to Sabbia, millennials expect 65% of their retirement income to come from personal sources.

Add to that the fact that longevity is increasing, and more people are going to personally be funding longer retirements, according to Ken Dychtwald, president and founder of Age Wave.

“Future generations will be funding much longer retirements than their predecessors, Dychtwald said.

Kevin Crain, head of workplace financial solutions for Bank of America Merrill Lynch, offered some advice on how advisors can use this retirement price tag to help consumers save more.

“[Considering retirement] as purchasing something in your future changes the dynamic of how you plan for that number,” he said. “So you're really trying to accumulate the assets and the ability to purchase a great future. And viewing it that way I think is a different approach to how traditionally advisors have worked with people on this subject.”

The study looks into why people aren't saving more, and found people offer a variety of reasons for not saving for retirement.

The top two barriers that people cited in the study are not having enough money left after paying basic expenses (41%) and paying down debt (38%).

The study also finds that there is a pretty significant “intention-action gap” in how Americans are saving for retirement. It seems Americans know they should be saving more, but they fail to do so.

According to Crain, “our study found that people have good intentions.”

However, the study finds there's a big difference between people's intentions and what they actually do.

On average, Americans said they think they should be saving about 25% of their disposable income each year.

“And yet people are saving just one-fourth of that,” Crain explained. “Americans are actually saving 5.5% of their disposable personal income.”

The savings rate has moved up from a low of about 3% during the recent recession, but it's still less than half the peak rate of 13% in the early 1970s, according to the study.