• Nearly half (46%) of individuals age 65 or older are concerned that a major health situation in their household could lead to medical debt or bankruptcy, according to a survey.
• Assuming they rely on Medicare — most in that age group do — it's worth seeing if there's a more cost-effective coverage option or if they qualify for assistance.
• Medicare's open enrollment is now underway through Dec. 7.

For retirees, unplanned medical expenses can upend their budget.

Indeed, while about 33% of Americans age 65 or older have at least $6,000 set aside for medical bills, 27% have less than $500 in savings for that purpose, according to a survey from MedicareGuide.com. Nearly half (46%) in that age group — who generally rely on Medicare for coverage — are very or somewhat concerned that a major health situation in their household could lead to medical debt or bankruptcy.

So how would they pay for the treatment cost of severe illness? More than 1 in 5 (22%) would turn to credit cards. Another 15% would tap retirement savings and 13% would draw on other savings. The survey was conducted in mid-September among a national sample of 1,176 U.S. adults ages 65 and older.

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If you're among those older Americans who struggle to pay for health care, be aware that there may be coverage options available that cost less. And with Medicare's open enrollment underway through Dec. 7, this is the time to find out.

In simple terms, this annual window is for adding or changing coverage related to an Advantage Plan (Medicare Part C) and/or prescription drugs (Part D). You can switch, add or drop those parts of your coverage, and changes go into effect Jan. 1. If you take no action, your 2021 plan generally would continue into 2022.

"Cash-strapped seniors may be eligible for plans that offer better savings and coverage than their current plan," said Jeff Smedsrud, a cofounder of MedicareGuide parent company HealthCare.com.

For beneficiaries with original Medicare only — Part A (hospital coverage) and Part B (outpatient care) — it may be worthwhile considering an Advantage Plan. These plans are offered by private insurance companies and deliver your Parts A and B coverage.

While basic Medicare has no out-of-pocket maximum, Advantage Plans do. They also typically include prescription drug coverage, as well as extras like dental, vision and hearing.

The average monthly premium for Advantage Plans will be $19 next year, down from $21.22 in 2021, according to the Centers for Medicare & Medicaid Services. However, some plans have zero premiums (although you generally would still be responsible for paying your Part B premium). Just be sure that your preferred doctors, hospitals or other providers are in-network or you could end up in a situation where services are not covered.

It's also important to make sure your prescription drugs are covered, whether it's through an Advantage Plan or a standalone Part D prescription drug plan. The average 2022 monthly premium for Part D coverage will be $33, up from $31.47 this year. You may also be able to get help paying for prescription drugs if your income is limited.

Also, depending on your income, you may qualify for a Medicare Savings Program, which is administered through state Medicaid offices and generally available to beneficiaries with low income.

There are several versions of the program, each of which depends at least partly on your income. The options also come with limits on your available resources (i.e., savings).

Depending on which program you qualify for, your Part B premiums could be paid, as well as other out-of-pocket costs such as deductibles, coinsurance and copayments.