You sign up for Medicare at 65, expecting health insurance to finally get simpler. The $202.90 monthly premium disappears from your Social Security check before you see it. You pay the $283 annual Part B deductible. Then something more serious happens, and you find out there is no ceiling on what you owe after that.
The average Medicare beneficiary spends more than $7,400 out of pocket on healthcare in a year. That number surprises most people, especially those who figured Medicare would cover the bulk of their costs.
What accounts for the gap isn't one hidden charge. It's a combination of rules that work very differently from most private insurance, and that regularly catch new enrollees off guard. Here are the costs and coverage gaps that most people don't see coming.
The Part B premium comes straight out of your Social Security check
Medicare Part B covers doctor visits, outpatient care, and most non-hospital services. It isn't free. In 2026, the standard monthly Part B premium is $202.90, up nearly 10% from $185 in 2025. That is the second-largest dollar increase in the program's history. For most enrollees, this amount is deducted automatically from their Social Security payment every month before the deposit hits their bank account.
On top of that premium, there is a Part B annual deductible: $283 in 2026. That resets each January. You pay the full deductible out of pocket before Medicare covers a single dollar of your outpatient care. Then, after you meet the deductible, you still owe 20% of every Medicare-approved charge for the rest of the year.
These three costs (the monthly premium, the deductible, and the 20% coinsurance) stack on top of each other and are ongoing. Most people who haven't looked closely at the Medicare cost structure going in are only vaguely aware of one of them.
Your 20% coinsurance under Part B has no annual ceiling
After your $283 deductible, Medicare pays 80% of the approved cost of most Part B services and you pay 20%. What's absent from that math is a cap. Original Medicare has no out-of-pocket maximum. That 20% adds up to whatever it adds up to, with nothing stopping it.
For a few routine doctor visits, the exposure is manageable. For cancer treatment, extended outpatient cardiac care, chemotherapy infusions, or physical therapy that runs for months, 20% of the total bills can run into tens of thousands of dollars. There is no point during the year when Original Medicare steps in and says you've paid enough.
Medicare Advantage plans (Part C) are required to have annual out-of-pocket maximums. In 2026, the cap is $9,250 for in-network services. Original Medicare has no equivalent. People who stay with original Medicare and want a ceiling on what they can owe in a given year need to buy a Medigap supplemental plan separately, which adds another monthly premium to the stack.
Higher earners pay significantly more, based on income from two years ago
If your 2024 income as a single filer exceeded $109,000, expect a larger Part B bill in 2026. Medicare adds a surcharge called the Income-Related Monthly Adjustment Amount, or IRMAA, on top of the standard premium. At the highest income bracket, the Part B premium reaches $689.90 per month, more than three times the base rate. IRMAA also applies to Part D, adding $14.50 to $91.00 per month depending on the income bracket.
The part that trips people up: IRMAA is calculated from tax returns filed two years earlier. Your 2026 premium is based on your 2024 income. Retirees who sold a home, did a Roth IRA conversion, or took large required minimum distributions in 2024 can land in a higher bracket for 2026 even if their current income is much lower. The surcharge also hits both spouses individually, so a couple with higher income pays the adjustment twice.
If a major life change has significantly lowered your income since the tax year Medicare is using, you can appeal. Submit Form SSA-44 to Social Security with documentation of the qualifying event. Retirement, divorce, loss of a spouse, and a significant reduction in income from work all qualify. Your premium can be recalculated using more recent income figures without waiting two years for the bracket to correct itself.
The Part A hospital deductible resets with each hospital stay, not each year
Medicare Part A covers inpatient hospital stays, and most people qualify for premium-free Part A. But it still comes with a deductible: $1,736 per benefit period in 2026. That is not an annual figure. It resets per hospital stay. If you're discharged, stay out of inpatient care for 60 days or more, and get readmitted, you owe another $1,736.
A benefit period begins the day you're admitted as an inpatient and ends when you've been out of inpatient hospital or skilled nursing care for 60 consecutive days. There is no annual limit on how many benefit periods you can have. Someone with two separate hospitalizations in one year, separated by 60 days, could owe the $1,736 deductible twice, plus the coinsurance that starts on day 61 at $434 per day.
After 90 inpatient days, you start drawing from a 60-day lifetime reserve at $868 per day. Once those lifetime reserve days are gone, at any point, Medicare pays nothing for additional inpatient hospital care. That 60-day reserve does not replenish each year.
Routine dental, vision, and hearing aren't covered
Original Medicare does not cover routine dental exams, cleanings, fillings, dentures, eyeglasses, routine eye exams, hearing aids, or hearing exams. These services are excluded from standard Medicare coverage. For people who had employer insurance that included all three, the gap comes as a hard surprise when they enroll and start trying to use benefits they expect to have.
The financial exposure is real. A basic pair of hearing aids averages $2,000 to $6,000 per pair. Dentures can run $1,500 to $3,000 per arch. Annual dental and vision costs that felt manageable as small copays on an employer plan suddenly become full out-of-pocket expenses. Medicare does cover cataract surgery, glaucoma screening for high-risk patients, and dental work that is directly required as part of a covered medical procedure, but that is the outer edge of what qualifies.
Many Medicare Advantage plans include dental, vision, and hearing benefits, which is one of the main reasons people choose them over original Medicare. What's included and at what cost varies significantly from plan to plan. If these benefits matter to your situation, reading the evidence of coverage document carefully before enrolling tells you what you're actually getting and what the plan's annual limits are for covered services.
Late enrollment penalties last for life
Miss your Part B enrollment window without qualifying coverage in place, and you'll pay a permanent penalty. The penalty is 10% of the standard Part B premium for every full 12-month period you delayed. Three years late means a permanent 30% surcharge on top of whatever the standard premium is that year. In 2026, that would add more than $60 per month to a premium that is already $202.90, for the rest of your time on Medicare.
Part D (prescription drug coverage) has its own separate penalty: 1% of the national base beneficiary premium for every month you went without creditable drug coverage. In 2026, that base is $38.99 per month. Go 24 months without coverage and you're adding roughly $9.40 to your monthly Part D premium permanently, with the dollar amount recalculated each year as the base premium changes.
The main protection: if you had active coverage through your own current employer or a spouse's current employer at age 65, you can delay Medicare without penalty, then enroll within eight months of losing that coverage. What does not protect you from penalties: COBRA, retiree health coverage from a former employer, or an individual marketplace plan. Those are not considered qualifying coverage for the purpose of delaying Part B enrollment.
Skilled nursing facility coverage drops off sharply at day 21
Medicare covers skilled nursing facility care after a qualifying hospital stay, but not indefinitely. The first 20 days are fully covered. Starting on day 21, you owe $217 per day in 2026. After day 100, Medicare pays nothing. If you need a nursing facility for rehabilitation after a major surgery or a hospital stay, that day-21 shift in costs isn't obvious until it happens.
A 40-day skilled nursing stay, not unusual after a hip replacement or stroke, works out to $4,123 in coinsurance from days 21 through 40 alone. A 60-day stay comes to $8,687. These costs don't count toward the Part B out-of-pocket total, and they don't reset with the calendar year. If you leave a skilled nursing facility, recover at home for more than 60 consecutive days, and then need SNF care again, a new benefit period starts and the coverage clock resets to day 1.
There is also the question of what qualifies you for SNF coverage in the first place. To get Medicare to pay for skilled nursing facility care, you need a qualifying inpatient hospital stay of at least three consecutive days before you go to the SNF. This requirement has its own trap, covered in the next section.
Hospital “observation status” days don't count toward nursing home coverage
To qualify for Medicare-covered skilled nursing facility care, you need at least three consecutive inpatient days in a hospital. The problem: not all hospital nights count as inpatient. If your doctor places you “under observation” rather than formally admitting you as an inpatient, those days do not count toward the three-day requirement, regardless of how many nights you spend in a hospital bed.
Hospitals use observation status frequently when monitoring patients whose condition hasn't yet clearly met the criteria for formal admission. A patient can spend two full nights in a hospital room receiving full hospital-level care, feel certain they were “admitted,” and then be told on discharge that the entire stay was outpatient observation, leaving them with zero days toward their SNF qualification.
The financial consequence can be severe. If you need rehabilitation in a skilled nursing facility following observation-only days and don't have the required inpatient stay, Medicare will not cover the SNF. Private-pay rates for skilled nursing average $350 to $600 per day. If you are receiving observation services for more than 24 hours, hospitals are required to provide a written notice called the Medicare Outpatient Observation Notice, or MOON. If you receive one, ask immediately whether reclassification as inpatient is possible and what the difference will mean for any follow-up care you may need.
Medicare stops at the U.S. border
Travel outside the United States and your Medicare coverage essentially ends at the border. Original Medicare generally does not pay for medical services you receive in a foreign country, even in an emergency. This surprises retirees who plan to travel internationally, spend winters in Mexico, or live abroad part of the year.
There are narrow geographic exceptions. Medicare may cover emergency care at a Canadian hospital if you're traveling between Alaska and another U.S. state and the nearest hospital happens to be in Canada. It may also cover inpatient care at a foreign hospital if you live in the U.S. and that foreign hospital is actually closer to your home than the nearest U.S. hospital that can treat your condition. These situations apply to a small number of people in specific border regions, not to someone getting care while traveling in Europe or Asia.
Some Medigap plans (C, D, F, G, M, and N) include foreign travel emergency coverage, but with a $250 deductible, an 80% coverage rate, a $50,000 lifetime cap, and a restriction that the emergency must begin within the first 60 days of a trip. Some Medicare Advantage plans include limited international emergency benefits as well. If you travel internationally with any regularity, it's worth verifying in writing what your plan actually covers before you go, and considering a separate travel health insurance policy for fuller protection.
Non-participating doctors can charge you more than Medicare's approved rate
Most providers who take Medicare have agreed to accept Medicare's approved amount as full payment. That's called accepting assignment. But some accept Medicare without agreeing to its rates. If your provider is non-participating, they are allowed to charge up to 15% above the Medicare-approved amount, and that extra charge is your responsibility on top of your normal 20% coinsurance.
These excess charges fall outside the Medicare cost-sharing structure entirely. They don't count toward your deductible, and they're not subject to any out-of-pocket cap. For expensive specialty care or procedures, 15% above the Medicare-approved rate can represent a significant bill. The charges also don't appear in any pre-appointment summary; you find out when you get the bill.
Eight states have banned excess charges: Connecticut, Massachusetts, Minnesota, New York, Ohio, Pennsylvania, Rhode Island, and Vermont. Everywhere else, you can protect yourself by confirming before any appointment that the provider accepts Medicare assignment. Medigap Plans F and G cover excess charges as part of their benefits. Providers who have fully opted out of Medicare are a separate category; they can charge any amount under a private contract, with Medicare paying nothing regardless of the service.
