If your health savings account (HSA) sits idle without any contributions to grow your funds, is it still an HSA? Yes, of course, but it won't do you nearly as much good.

Many employers and financial planners encourage people with HSAs to put some money into their accounts so the balance can grow and compound over time, potentially covering more out-of-pocket health costs.

Half of HSA owners did fund their accounts to some degree in 2017, and only 13% contributed the maximum amount allowed, according to new data from the Employee Benefit Research Institute (EBRI), a nonprofit research group in Washington. But 36% of HSAs didn't receive any contributions, either from employee or employer.

Of the HSAs with contributions, the average employee contribution was $1,949, with employers kicking in $895 on average, according to EBRI.

Why aren't more than a third of HSA owners contributing to their accounts at all? Some accounts may belong to people who've disenrolled from high-deductible health plans in favor of a more comprehensive health plan, making those HSA owners ineligible to contribute money. For those still eligible but not contributing, a combination of factors is at play.

Jobs in the gig economy are notoriously unpredictable and low-paying. Fewer raises for employees and rising housing and healthcare costs also constrain workers' ability to contribute, said Steve Wojcik, vice president of public policy at the National Business Group on Health in Washington, which represents large employers, those with 10,000 or more workers.

"People's wages have kind of stagnated, and a lot of people are living paycheck to paycheck and healthcare costs are going up," he said. "All those things work against investing and building up your account."

"I guess they're hoping that at some point they'll be able to put money in there or be lucky enough to have an employer that puts money in for them," Wojcik added.

Something is better than nothing

A brief review is in order: As long as you have a qualified high-deductible health plan and are not on Medicare, you are eligible to contribute to your HSA. Assuming you're not self-employed, your employer may contribute to your HSA as well. Even a little bit helps.

For 2019, total contribution limits, including those from employer and employee, top out at $3,500 for single policies and $7,000 for family coverage. That's an increase of $50 for singles and $100 for families from 2018 maximum contribution levels.

HSA contributions are either pre-tax if you're employed and your employer provides you with the option or tax-deductible if you're self-employed or don't have the option to set aside pre-tax funds from pay, and they grow tax-free. As if that's not enough, distributions are also tax-free as long as you use the money for qualified health expenses. That's the triple tax benefit HSAs are known for.

What's more, you can continue to withdraw your HSA funds once you're on Medicare even though you're no longer allowed to contribute to the account.

Most people (82%) enrolled in HSAs as part of a high-deductible health plan have them through a large employer, those with 50 or more workers, according to data from America's Health Insurance Plans (AHIP), a trade group in Washington. The remainder either have them through small employers or buy them on the individual market.

The good news is many of those large employers help their workers with contributions, especially when workers first switch from a more comprehensive health plan to a high-deductible plan that can cause sticker shock until that deductible is met, said Wojcik of the National Business Group on Health.

For 2019, 61% of large employers who are offering high-deductible plans with HSAs say they will contribute to those accounts, with a median HSA contribution of $500 for individuals and $1,000 for families, according to NBGH. Median means half of respondents plan to contribute more and half will contribute less.

The average account balance varies by how long owners have had their HSA, said Paul Fronstin, "director of EBRI's Health Research and Education Program.

"Most accounts are new, so most balances are going to be low," he said. But that can change.

"The longer you have had the account, the higher your personal contribution and the more likely you are to invest...instead of just leaving it in a non-interest or token interest-bearing account," he said.

Over time, more people start to see the benefits of HSAs' triple tax advantage and contribute more and invest more -- even if they have to take more money out, EBRI found.

Compound It! is your weekly update of achievable, effective, no-nonsense HSA saving and investment advice, delivered by people who make it work in their own lives. For the latest info about your health and financial wellness, be sure to check out the HSA Learning Center, and follow us on Facebook and Twitter.

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