You pay into Social Security your whole working life. After you retire, would you prefer Social Security pay you back:

A. $286,272

B. $364,548 or

C. $436,956?

This might sound like a no-brainer, but more than 90 percent of men choose A or B, according to Frank Thomas, a Richard Stockton College professor and a certified public accountant in Port Republic.

The big differences in benefits collected result from following different Social Security retirement strategies - or not having a strategy at all.

Thomas discussed such strategies in a January article in the Journal of Accountancy titled "CPA personal financial advisers should run the numbers on Social Security, and for their married clients, that goes double."

The numbers above - from the chart accompanying this story - are estimates of what a 58-year-old earning $50,000 per year will collect from Social Security, assuming he or she lives to the average life expectancy for someone at age 65.

The amounts differ so much because Social Security increases the benefit paid for each month up until age 70 that a recipient delays collecting.

The first number - $236,000 - is how much those retiring early and starting their benefit at age 62 will receive through age 83. (While someone born in 2005 can expect to live to 78, someone already 65 will live on average to 83.)

Those who start collecting Social Security at their full retirement age of 66 will receive a monthly benefit

57 percent larger, giving them $78,000 extra during that typical lifespan, even though they began collecting four years later.

And if he or she waits until age 70 to start collecting, the monthly benefit will be 36 percent bigger than at 66 and 147 percent greater than at 62.

The key, of course, is to have other money to live on until 70 - savings or other retirement benefits, or earnings from continuing work or a spouse's work.

"If you don't have other assets, you don't have options," Thomas said. "But if you do have money in a 401(k), you should look at it."

If someone has a spouse - especially a younger or female spouse (women typically live two to three years longer than men) - the financial advantage of delaying benefits gets even larger.

For as long as they live, surviving spouses collect the full Social Security benefit of their predeceasing spouses, typically adding about five more years of getting the much higher amount.

Delaying the start of benefits worked well for Dr. Howard and Shirley Barsky, of Atlantic City. They highly recommend the strategy.

Dr. Barsky, now 85, said he kept working until he was 70. Shirley Barsky, who is five years younger than her husband, began collecting when she was 65.

"You get the maximum benefit that way," he said.

"A lot of people take Social Security at 62. They don't realize how much it is probably costing them," Shirley said. "It's true that some of them might die young, but some of them will live a lot longer."

Thomas said that even for those who are well off, with savings and private pensions, maximizing the Social Security benefit can make a big difference in their later years.

"Even for the wealthiest 40 percent of retirees, Social Security still makes up about a third of their retirement income, according to Vanguard," he said.

Another benefit, he said, was that the increasing delayed benefit is protected from inflation - adjusted annually to take account for changes in the cost of living.

And Social Security benefits are taxed less than other retirement income sources.

"You'd prefer to collect Social Security over taking money out of a 401(k) ... 100 percent of that is taxed, but at most, 85 percent of Social Security is taxable," Thomas said.

The SSA Do-Over

Thomas is taking a sabbatical to research other, less conventional Social Security strategies, in particular the SSA Do-Over.

Since 1964, beneficiaries have been allowed to pay back all of the Social Security payments they've received and switch to a delayed, higher benefit level.

"The Social Security Administration felt it was unfair to make the decision (when to begin collecting benefits) irreversible," he said.

Amazingly, the benefits are paid back without interest, and any taxes on them are recovered.

Thomas said he ran into someone at the gym who had done a Do-Over.

"He took early retirement because he felt his health was poor, but then had the time to devote himself to physical fitness," he said. "He has a lot of money in money market accounts, so he can take advantage of the Do-Over strategy."

Others simply play the Do-Over as a way to get free money for investment - investing all of the benefit payments, and then as late as age 70, paying back the principal and keeping the interest or capital gains from several years.

A Boston College working paper in March on the Do-Over strategy estimated it could wind up costing the Social Security Administration $5.5 billion to $11 billion annually, Thomas said.

Of course, this and other strategies depend on living to an age at least somewhat near typical longevity.

"The risk is if you pay back that Social Security money, you're going to have egg on your face if you die soon thereafter," Thomas said.

"It's also very speculative to tell somebody who is 60 to start collecting at 62, bankroll the money and start over at age 70," he said. "Who knows if this will be available in 10 years."

Thomas hopes to develop techniques that financial professionals can use to determine if a Do-Over is a good investment for an individual.

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