But there are a number of qualifiers that may make health savings accounts a poor fit. For starters, they're not available to everyone who might be interested. In 2013, 47 percent of employers offered an HSA, according to Aon Hewitt, although another 34 percent said they plan to add them in coming years.
Nor are they always in budget. Health savings accounts are usually paired with high-deductible insurance plans, which offer lower premiums but require higher out-of-pocket costs before coverage kicks in. For 2014 the minimum deductible for an individual is $1,250, and for a family it's $2,500, said Slott. Maximum out-of-pocket costs on such plans are $6,350 and $12,700, respectively.
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"Usually if they're using an HSA in a company plan, it's because they're high-income earners," said Beck. To use one of the accounts for retirement planning, deep pockets are practically a requirement—to max out the account annually and pay some current health-care costs without tapping the account, so the tax-advantaged assets can grow.
Whether by accident or design, consumers aren't carrying over much. In 2013 the average HSA balance was just $2,311, reports the EBRI, and the average rollover from 2012 was $1,165. Individuals who had used an account for at least five years had saved more—an average $3,491.
Even wealthier consumers, who won't have trouble hitting the max, should scrutinize investment options in health savings accounts. "Not all employers offer an option to invest those assets in a growth type of investment," said Erika Safran, a certified financial planner and founder of Safran Wealth Advisors in New York City. Most of the time, the funds are in money market accounts. "The objective of that is not long-term growth," she said. "It's long-term safety and liquidity."
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When there are other investments available, commissions and other charges can eat into returns, offsetting any upfront savings from lower premiums, said Rick Kahler, a certified financial planner and founder of Kahler Financial Group in Rapid City, South Dakota. "There's not much we can control when it comes to the market, but what we can control are the taxes, transaction costs and fees," he said.
Consumers will also be better served by first maxing out plans with higher annual contribution limits—401(k)s and, for individuals, IRAs—before weighing an HSA for anything more than short-term medical needs, said Beck. "From a retirement-planning perspective, I don't consider it the first place to save money," she said.