Personal Finance

This account might cause snags when you claim Social Security

Key Points
  • You can only put money in a health savings account if you are covered by a high-deductible insurance plan, which means you must stop those contributions once you're on Medicare.
  • If you accept a retroactive lump sum from Social Security because you enroll after your full retirement age and you haven't yet signed up for Medicare, that health coverage would be retroactive, as well.
  • Any money paid into an HSA during that period would be considered "improper contributions" and subject to taxes.
Abel Mitja Varela | Vetta | Getty Images

If you regularly contribute to a health savings account and plan to tap Social Security past your full retirement age, watch out.

For starters, that's because you can no longer contribute to an HSA once you're on Medicare, no matter whether you sign up just for Part A hospital coverage (which is free) or additional parts of the program that require premiums.

While this sounds straightforward, complications can arise for people who delay both Social Security and Medicare.

Here's why: When you delay claiming Social Security beyond your full retirement age, you're generally offered a lump sum in retroactive benefits of up to six months, dating no further back than your full retirement age — now 66 for most people.

If you're not yet on Medicare when that happens and are contributing to an HSA, there's the potential for issues.

"The problem is that if you take the lump sum from Social Security, it triggers Medicare Part A being effective retroactively, as well," said certified financial planner Peggy Sherman, a lead advisor at Briaud Financial Advisors in College Station, Texas. "So if you made contributions to an HSA during that time, you face an excise tax of 6% on those contributions in addition to income taxes."

The problem is that if you take the lump sum from Social Security, it triggers Medicare Part A being effective retroactively as well.
Peggy Sherman
Briaud Financial Advisors

Anyone in that situation should remove those so-called improper contributions and alert their employer to remove any matching contributions made on their behalf, she said.

"That would need to be done by the tax return filing date for the year it's happening in," Sherman said. "If you sign up for Social Security this year, you have to remove those contributions by April 15 of next year to avoid the tax issue."

With more people staying in the workforce well into their 60s and 70s, it's a situation that's likely to crop up as those workers delay claiming Social Security and enrolling in Medicare.

As long as you have qualified health insurance through work, you can delay going on Medicare without facing a late-enrollment penalty. This means you can continue contributing to your HSA in combination with a high-deductible health plan.

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For 2019, the maximum HSA contribution is $3,500 if you have self-only insurance, and $7,000 for family plans. People age 55 and older are allowed to put in an additional $1,000. The money comes with a triple tax benefit: Contributions are deductible, the money grows tax-free and withdrawals are tax-free as long as they are used to pay for qualifying medical expenses.

Delaying Social Security also holds appeal: Your benefits grow by 8% each year you delay up until age 70.

The lump sum offered by the government, and retroactive Medicare coverage, depends on how far beyond your full retirement age you are when you claim Social Security. As mentioned, you can get up to six months' worth of retroactive benefits.

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For example, say your full retirement age is 66 and you tap Social Security three months after your birthday. The government would offer to give you a lump sum worth those three months of benefits, which would make your effective date retroactive to your birthday. Sign up six months or more after your full retirement age, and you'll be offered a six-month lump sum for retroactive benefits and effective date.

If you think you'll accept a lump sum, you need to stop your HSA contributions before that retroactive date would kick in to avoid the tax complications, Sherman said.

She also pointed out that rejecting the lump sum — and retroactive effective claiming date — isn't necessarily a bad idea anyway.

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"If they say we'll give you a lump sum worth six months and you say no, your base benefit will be 4% higher," Sherman said.

In other words, based on an 8% increase in your base benefits for each year you delay claiming Social Security, the effective date that's six months later would mean a permanent 4% increase in monthly benefits. If you were to take the lump sum, your base benefit would be pinned to that earlier date of claiming, making it less.

If your Medicare coverage becomes effective in the middle of the year, you can make HSA contributions that are proportional to the time you were still eligible to contribute. That is, each month of eligibility would be 1/12th of the maximum amount you can put in.

And of course, while you can no longer contribute to an HSA once you're on Medicare, you can use the money to pay for premiums, copays, deductibles and any other qualifying medical expense, Sherman said. Also, once you turn 65, there is no longer a 20% penalty if the money is used for nonmedical expenses.

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