NEW YORK (MainStreet) — Ask a financial advisor about investing, planning for retirement or developing a savings strategy and watch the pie charts, income simulations and risk/reward scatterplots start flying across the desk. Ask that same advisor when to start taking Social Security benefits – crickets.

The challenge is determining how to gain maximum after-work income while retaining your retirement savings as long as possible – and provide the highest surviving spouse benefits. With all of the options available to a pre-retirement married couple, that can mean the consideration of thousands of possibilities.

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According to Financial Engines research, seven out of ten current retirees say Social Security benefits are a major source of their retirement income, while the Social Security Administration says about one in four married couples -- and nearly half of unmarried individuals -- rely on Social Security for 90% or more of their income. So knowing when to trigger Social Security benefits for maximum income is a major decision. Financial Engines has developed a free online planning tool that crunches the numbers for you.

"Social Security is incredibly complex, and most people miss out on tens of thousands of dollars in benefits because they don't have anyone to help them figure out the best way to claim," says Christopher Jones, Financial Engines chief investment officer. "By considering Social Security in combination with your 401(k), you can unlock hidden value and dramatically increase your retirement income."

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By entering birth date and income information, users can develop either an individual or household strategy to determine when to trigger Social Security benefits. Accounting for multiple income sources and the life expectancies of both spouses in a married household, the tool analyzes the most efficient deployment of earned benefits, as well as spousal and survivor benefits, then provides a printable action plan for when to file with Social Security for each benefit.

Considering Social Security strategies as a household decision rather than an individual one can maximize the benefits for the spouse who lives the longest. Even for middle income retirees, the various scenarios can vary by hundreds of thousands of dollars.

"Delaying Social Security is a screamingly good deal, especially in today's low interest rate environment," adds Jones. "For each year participants defer claiming Social Security, they receive a 6-8% increase in lifetime benefits, under current conditions, which can make a big difference in their quality of life in retirement."

Fully 60% of claimants file for Social Security benefits as soon as they are eligible, according to Financial Engines research, "ignoring or underestimating the impact on the income of a surviving spouse, the inflation protection inherent in Social Security, and the higher lifetime benefits associated with delayed claiming. The amount of additional expected lifetime benefits gained with the right claiming decision can be significant: up to $100,000 more for individuals and $250,000 for married couples."

--Written by Hal M. Bundrick for MainStreet