With 401(k) plans turning 40 years old, a Schwab Retirement Services survey finds that a majority of boomers feel their own 401(k) plans are in better shape than ever.

In fact, 75% of boomer respondents believe that, and just 16% say they expect to work during retirement because they think they’ll need the money. Contrary to numerous headlines, 40% of this confident crew plans to work in some way during retirement because they want to, while 25% say they don’t plan to work at all.

They also feel pretty good about the prospect in that close to three quarters say they’ll have a better quality of life in retirement than their parents — 78% also think it’ll be better than that of their juniors, too.

But that doesn’t mean that everyone feels prepared. Not only do 36% of respondents not know how much they need to save for retirement, 25% aren’t sure about the percentage that needs to go into their 401(k)s. And 20% don’t know how to get the money out of their plans once it goes in.

“Forty years ago, we might not have anticipated that the weight of Americans’ retirement would rest so squarely on the shoulders of the 401(k) plan,” Catherine Golladay, senior vice president  of participant services and administration at Schwab Retirement Plan Services, says in a statement.

Golladay adds, “While it is encouraging to see that so many boomers are confident in their ability to retire comfortably, it is not surprising that a large percentage of them are feeling unprepared as they approach the end of their careers.”

Whether they realize it or not, even the confident ones may not be quite as prepared as they think, according to a NextAvenue report. Citing the 28th annual Retirement Confidence Survey from the Employee Benefit Research Institute, the report points out that people haven’t been as diligent as they could be about figuring out how much they need to save, how much they’ll need to live on or how much they’ll get from Social Security — so they don’t really have a handle on how well prepared they are to pay their way through retirement.

And nearly half — 46% — will be relying on their 401(k)s as their largest source of income once they do retire, despite their lack of confidence in whether the account balance is big enough to get them through. Other savings and investments outside their 401(k)s take second place, at 23%, with Social Security being the largest source for 19% and a pension for 11%.

The great majority, 81%, expect their 401(k) savings to pay for everyday expenses, but others intend it to cover travel (40%), health care expenses (36%), housing (21%), medical expenses (20%) or even take care of their kids’ and grandkids’ financial needs (8%).

Whether their 401(k)s are up to the challenge is yet to be determined.

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