Though retirement should be an exciting period of life in theory, for plenty of seniors, it's a stressful one in practice. That's because many retirees are caught off-guard by the expenses they inevitably face. And if there's one expense that's more likely than not to go up in retirement, it's healthcare. In fact, senior medical care can be so onerous that in a recent study by Voya Financial, workers listed it as their single most worrisome expense.

If you're concerned about healthcare in retirement, you're clearly in good company. But you should know that there are steps you can take to ease the burden and take some of the financial pressure off. Here are just a few.

Doctor sitting across from older patient

IMAGE SOURCE: GETTY IMAGES.

1. Sign up for Medicare on time

Though Medicare Part A, which covers hospital visits, is generally free for enrollees, Part B, which covers doctor visits and diagnostics, comes at a premium. But you can do your part to keep that premium to a minimum by enrolling in a timely fashion.

Your initial Medicare enrollment window kicks off three months before the month of your 65th birthday and ends three months after the month of your 65th birthday. All told, you have seven months to sign up for Medicare coverage without incurring a penalty. But if you wait too long to enroll, you could see your premiums rise by 10% for every 12-month period during which you were eligible for coverage but didn't sign up.

Now there is an exception to this rule. If you're still covered by a group health plan through an employer (either yours or your spouse's) by the time your initial Medicare enrollment window rolls around, you can hold off on signing up without having to worry about that Part B penalty. Rather, you'll get a special eight-month enrollment period that begins the month after you separate from your employer or the month after your group coverage ends -- whichever comes first.

Either way, figure out when you're supposed to sign up for Medicare. This way, you'll have coverage when you need it and avoid penalties that add to your costs throughout retirement.

2. Review your drug plan year after year

When you sign up for Medicare, you'll also need a Part D plan to cover prescriptions. You'll obviously want to research the right plan initially for optimal coverage, but don't settle on a single plan and stick with it for the long haul. Plan formularies tend to change from year to year so that you might get great coverage for the medications you take at one point, and then get lousy coverage at another. Furthermore, as you age, your prescription needs are likely to change, so plan on reassessing annually to get the best coverage at the lowest cost.

3. Take advantage of Medicare's free preventive health services

Medicare doesn't just want to take your money; it actually offers a host of free services designed to help you keep tabs on your health. It pays to take advantage of these services every year, which run the gamut from depression screenings to diabetes testing. You're also entitled to a free well visit every year with your doctor, and that's something you'll want to commit to. Getting ahead of medical issues before they escalate is a great way to keep your costs manageable, and sometimes, all you need is a little dose of vigilance to nip health problems in the bud.

4. Invest in long-term care insurance

While doctor visits and prescriptions can be expensive during retirement, they pale in comparison to the colossal expense that is long-term care. It's estimated that 70% of seniors 65 and over will need some type of long-term care in their lifetime, and if you're forced to cover that expense on your own, it could very well wreak havoc on your finances later in life. Rather than run that risk, look into long-term care insurance during your 50s or early 60s. At that stage of life, you're more likely to not only get approved for a policy, but also snag a long-term discount on your premiums as a result of your good health.

Clearly, healthcare in retirement is a major concern, as it should be. But if you take steps to lower your costs, you'll make an otherwise whopping expense just a bit more manageable.

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