4 Medicare Mistakes Retirees Should Avoid in 2026

For millions of older Americans today, Medicare serves as a key source of health coverage. But Medicare's rules can be confusing -- especially if you're new to it.

If you're turning 65 in 2026, it means you're old enough to get covered through Medicare. But it's important to understand how the program works. Here are a few mistakes you should make every effort to avoid.

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1. Missing your initial enrollment deadline

You might assume that you can only sign up for Medicare once you turn 65. But actually, your initial enrollment period for Medicare lasts seven months, and it begins three months before the month of your 65th birthday. It then ends three months after that month.

It pays to enroll in Medicare on time for a couple of reasons. First, if you've left your job, you don't want to go without health insurance. All it might take is a single ER visit while uninsured, and it's bye bye, IRA balance.

Secondly, if you're late signing up for Medicare, you'll risk lifelong surcharges on your Part B premiums, which are expensive already. You'll also risk surcharges on your Part D drug plan premiums if you go too long without prescription coverage.

Now one thing you should know is that if you're still working when you become eligible to enroll in Medicare, you may not be penalized for signing up late if you have qualifying group health coverage at the time. But make sure your employer plan meets that requirement before delaying your enrollment.

2. Not buying a Medigap plan right away

There are numerous costs you might incur as a Medicare enrollee for covered services like hospital care and diagnostic tests. Those deductibles and coinsurance costs could add up and eat into your Social Security benefits in a scary way.

A good way to defray some of those costs is to buy a Medigap plan. But it's a good idea to sign up for Medigap right away.

Your initial Medigap enrollment window spans six months, and it starts the month you're 65 or older and have Part B coverage. During that time, you can't be denied coverage. But if you wait beyond that window, approval for coverage isn't guaranteed, and you could end up with exorbitant premium rates.

3. Signing up for a Medicare Advantage plan without understanding the drawbacks

There's a reason many older Americans choose Medicare Advantage over original Medicare. Medicare Advantage plans are plans offered by private insurers that must offer at least the same level of coverage as original Medicare.

It's common, though, for Medicare Advantage plans to offer benefits beyond what original Medicare gives enrollees. And unlike original Medicare, Medicare Advantage plans put a cap on annual out-of-pocket spending. When you're on a fixed income that's a mix of Social Security and a modest nest egg, that's an important thing.

But while Medicare Advantage has, well, some advantages, it also has some big drawbacks. For one thing, these plans typically limit you to narrow provider networks, which means your favorite doctor may be off limits.

Also, you may be required to get prior authorization for treatments that are more costly or complex. That could be a huge hassle and result in a delay in care.

Before you decide that Medicare Advantage is right for you, do your research. Once you understand the pitfalls, you may decide that original Medicare is a better bet.

4. Assuming Medicare will cover all of your needs

You might assume that as long as you're willing to pay your copay or deductible, Medicare will cover every health-related service you might need. In reality, there are a good number of services Medicare won't pay for, including dental care, eye exams, and hearing aids.

Medicare also will not pay for long-term care. If you end up needing a home health aide or assisted living because your mobility declines as you age, that cost will be yours to bear.

It's important to understand what Medicare will and won't cover so you can save and plan accordingly. For services like dental and eye exams, a good bet is to save money in a health savings account you can dip into.

It's also a good idea to buy long-term care insurance. If you're already old enough to enroll in Medicare, it may be a challenge to find affordable premiums, but there's no saying it can't be done.

Educating yourself on how Medicare works could save you money and aggravation. Read up on Medicare now so you're able to avoid these big mistakes in 2026.

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