3 Medicare Rules All Retirees Need to Know in 2026

Medicare, like Social Security, is a program that millions of older Americans rely on heavily. Whereas Social Security pays monthly benefits to eligible retirees, Medicare provides health coverage to qualifying seniors.

It's important to know the ins and outs of Medicare to make the most of your benefits if you're enrolled and avoid unpleasant financial surprises. With that in mind, here are three important Medicare rules to know about in 2026.

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1. What costs to expect

The amount of money you pay for Medicare coverage depends on the plan you choose. There's no universal Medicare Advantage plan or Part D drug plan premium. The cost there hinges on your plan of choice. And from there, your out-of-pocket costs will depend on your plan's coverage, the services you need, and the medications you take.

But there are certain universal Medicare costs all enrollees can expect in 2026. And it's important to know what those entail.

For one thing, Medicare's standard monthly Part B premium is $202.90 in 2026, an increase from $185 in 2025. The annual deductible under Medicare Part B is $283, up from $257 last year.

Not all Part B enrollees pay the same premiums for Medicare. If you're a higher earner, you may be subject to an income-related monthly adjustment amount that results in higher premium costs.

Meanwhile, most Medicare enrollees do not pay a premium for Part A. But the standard inpatient hospital deductible is $1,736 in 2026, up from $1,676 last year.

The amount you'll pay for daily coinsurance beyond your 60th day of a hospital stay will be $434 in 2026, up from $419 in 2025. And the daily coinsurance rate for care in a skilled nursing facility is $217 this year, up from $209.50 last year.

2. When to enroll

Clearly, there are many costs you might incur as a Medicare enrollee. So it's important to do what you can to keep your premium costs to a minimum. And a good way to avoid surcharges on your premiums is to enroll on time.

Your initial Medicare enrollment window spans seven months, starting three months before the month of your 65th birthday and ending three months after that month. Failing to enroll during that period could leave you subject to surcharges on Part B for life, as well as surcharges on whatever Part D plan you choose.

Now that said, you may get extra time to sign up for Medicare without penalties if you're covered by a qualifying employer health plan at the time of your initial enrollment window. That generally means being on a plan with 20 or more employees.

If you're on a qualifying group plan, you'll get a special enrollment window to sign up for Medicare that will begin after you separate from your employer or your group health coverage ends. But do keep in mind that you must have active health coverage to qualify for a special enrollment period. COBRA, for example, does not count.

3. How supplemental insurance works

We just discussed the many costs associated with Medicare coverage above. And you should know that a good way to protect yourself from those costs is to secure Medigap, or supplemental insurance, early on.

Medigap works with original Medicare (not Medicare Advantage) to pick up the tab for expenses like deductibles and coinsurance you're responsible for as an enrollee. It won't, however, cover services Medicare itself won't pay for, like dental care or eye exams.

Medigap plans are sold by private insurers, and you pay a separate premium for your plan on top of Part B. The best time to enroll in Medigap is during your initial six-month open enrollment period, which starts the month you're 65 or older and enrolled in Part B. During this time, Medigap plan issuers must sell you a policy at the best available rate.

Outside of that period, Medigap providers can try to deny you coverage based on pre-existing conditions. They can also jack up the cost of your premiums based on said conditions, making that coverage unaffordable.

The more you know about Medicare, the better you can budget and plan for retirement. Keep these points in mind whether you're new to Medicare this year or are simply trying to learn more about the program.

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