Bone up

It might not come as a surprise, but Americans' knowledge of the intricacies of Social Security and Medicare is lacking. So one way to make sure that you maximize your benefits is to learn as much as possible in advance about the ins and outs of what could represent a big portion of your retirement plan.

"Individuals should be aware of what happens to their Social Security benefits so they can plan around them by increasing their savings or adjusting their retirement age," said Copeland. "Any changes that may be made to Social Security will have some effect on future workers' retirement finances. Accordingly, workers must adjust to any changes, which are fairly limited to saving more or working longer."

Greenwald said most people do not maximize their benefits because they are not tactical about when to claim benefits, especially those strategies a husband and wife can use. "In some cases, for example, a lower-paying wife should claim as early as possible and a husband as late as possible," Greenwald said. "The key is to do a careful analysis. Most people do not do that, and they should."

Getting a handle on the strategies that a husband and wife should use is critical, according to Rappaport. "My best advice to people is: Be sure to evaluate claiming alternatives and consider spouse benefits when they do. Many people will benefit from claiming later, and too many claim early."

For her part, Altman said that workers who are insured under Social Security have discretion concerning when to claim their retirement benefits. "The decision regarding the age to first claim benefits, which is an actuarially neutral decision from Social Security's perspective, turns on personal circumstances," she said.

If you're unsure of your expected benefit, get an estimate from the Social Security Administration website (you can find the agency's benefits calculators here.) Also read the National Academy of Social Insurance report "When to Take Social Security: Questions to Consider."

Save early, save often

Social Security is supposed to provide a basic floor under retirees' incomes, but it is only one source of retirement income, the others being workplace pensions and other private savings, said Toder.

"Middle- and upper-income workers have always needed to supplement Social Security with resources from other sources to maintain their living standards in retirement," said Toder. "Given the decline in the number of workers covered by defined-benefit plans and the likelihood that federal budgetary conditions and rising medical costs will compel future retirees to bear a higher share of their health costs than they do today, it is more important than ever to start to save for retirement early."

For his part, Smetters said people need to increase their savings. "People still need to save more, especially as Medicare is also in trouble," he said. "Families who are only saving in their employer-based plans are probably not saving enough."

Others agree with that advice. "The (trustees) reports are another reminder that we all need to save more, save often, essentially save until it hurts," said Michael Wilson, CEO of the International Foundation of Employee Benefit Plans. "Social Security was not intended to provide an individual's complete retirement income."

Don't rely on housing wealth

In addition, Smetters said, Americans should avoid depending too much on accumulated housing wealth. "Despite the obvious risk of fluctuating housing prices, people often decide later not to downsize as they previously planned," he said.

Current beneficiaries go back to work or keep on working

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Current beneficiaries, unfortunately, cannot do much to change their benefit, said Copeland. They do have one option, though. "They could go back to work or continue work, and any earnings penalty against their benefits will lead to their benefits being actuarially adjusted upward to account for the penalty," he said. "It is somewhat of a forced savings method."

If you do go back to work while collecting, don't exaggerate the impact of the "earnings tax" on Social Security benefits, said Smetters. "For most households, the additional credit to Social Security benefits from delaying the collection of benefits fully offsets the tax, he said.

Medicare is the bigger problem

The real problem is Medicare, said Salisbury and others. "Medicare now pays an average of half, with new income-based premiums," Salisbury said. "Assume it drops over time to pay 25% and that premiums continue to rise. Plus, health costs continue at a high rate. At retirement at 65 or older, assume you need $300,000 set aside for retiree medical and $300,000 for long-term care if you do not buy a long-term-care insurance policy. This is individual, not couple. Then customize this to your family history and the like. Better to have oversaved and underconsumed than the opposite."

"The bottom line is that households need to start viewing Social Security as a backup layer of security rather than as a primary pension plan," said Smetters.