Yes, Medicare Advantage plans are legally required to cover inpatient hospital stays. Every Medicare Advantage plan must cover at least everything Original Medicare covers under Part A, which includes hospital services, skilled nursing care, and some home health services. But the way you pay for that coverage, and the hoops you may need to jump through to get it, can look very different from Original Medicare.
What Medicare Advantage Must Cover
By federal law, Medicare Advantage plans must cover all medically necessary services that Original Medicare covers. That includes inpatient hospital care, surgeon and physician fees during your stay, nursing services, meals, medications administered in the hospital, lab tests, and any medically necessary procedures. If Original Medicare would pay for it during a hospital stay, your Advantage plan has to cover it too.
Where things diverge is in the details: how much you pay out of pocket, which hospitals you can use, and whether your plan needs to approve the stay in advance.
How Hospital Costs Differ From Original Medicare
Under Original Medicare in 2026, you pay a $1,736 Part A deductible per benefit period, then nothing for the first 60 days. After that, daily copays kick in: $434 per day for days 61 through 90, and $868 per day if you dip into your lifetime reserve days (you get 60 of those total, ever).
Medicare Advantage plans structure costs differently. Instead of that single large deductible, many plans charge a daily copay from day one of your hospital stay. The exact amount varies by plan, and some charge different rates for different day ranges. This means a short stay of a few days could cost you more or less than it would under Original Medicare, depending on your specific plan’s copay schedule.
The key financial protection with Medicare Advantage is the annual out-of-pocket maximum. In 2025, plans cannot set this limit higher than $9,350 for in-network services or $14,000 for in-network and out-of-network services combined. Once you hit that ceiling, the plan covers 100% of your Part A and Part B costs for the rest of the year. Original Medicare has no equivalent cap, which means a lengthy hospitalization under traditional Medicare can be far more expensive if you don’t carry supplemental coverage.
Prior Authorization Can Delay or Deny Coverage
This is where Medicare Advantage gets complicated. Nearly all Advantage plans require prior authorization for certain types of care, and inpatient hospital stays are one of the most common services that need pre-approval. Your plan essentially wants to confirm that the admission is medically necessary before agreeing to pay for it.
In practice, this means your doctor or hospital submits a request to your plan, and the plan reviews it before (or sometimes shortly after) you’re admitted. If the plan approves it, your stay is covered under your plan’s normal cost-sharing rules. If it’s denied, you could face paying the full cost yourself, seeking care elsewhere, or going through an appeals process. Prior authorization requirements have drawn criticism because they can lead to delays or denials of care that is medically appropriate.
If your plan denies a prior authorization request and upholds that denial on internal appeal, the case is automatically forwarded to an independent review entity for an external review. Federal rules also prohibit Advantage plans from creating their own internal coverage criteria when Original Medicare has already established coverage standards for a service. Plans can only use prior authorization to confirm that diagnoses or medical criteria are present, not to impose stricter requirements than traditional Medicare would.
Emergency admissions are the exception. If you’re admitted through the emergency room for an urgent, life-threatening condition, plans must cover the stay regardless of prior authorization. You cannot be penalized for not getting pre-approval when the situation was a genuine emergency.
In-Network vs. Out-of-Network Hospitals
If you have an HMO-type Medicare Advantage plan, you’ll generally need to use hospitals within the plan’s network for coverage to apply. HMOs typically don’t cover out-of-network care at all except in emergencies. PPO-type plans give you more flexibility: they’ll cover out-of-network hospitals, but your cost sharing will be higher, and the out-of-pocket maximum for combined in-network and out-of-network care rises to as much as $14,000.
For planned surgeries or scheduled admissions, this distinction matters a lot. Check that both the hospital and the physicians who will treat you are in your plan’s network before an elective admission. Out-of-network providers at an in-network hospital can still result in higher costs.
The Observation Status Problem
One issue that catches many Medicare beneficiaries off guard is hospital observation status. You can spend days in a hospital bed receiving treatment and still not be classified as an “inpatient.” If the hospital places you under observation status, you’re technically an outpatient, and the billing rules change significantly. Medicare.gov advises Advantage plan members specifically to check with their plan about how observation status affects costs and coverage, because the rules vary.
This distinction matters most when you need skilled nursing care after your hospital stay. Under Original Medicare, you need at least three consecutive days as a formal inpatient (not under observation) before Medicare will cover a skilled nursing facility. That same requirement can apply to Advantage plans, though many Advantage plans have the option to waive the three-day minimum. If your plan offers this waiver, you could qualify for skilled nursing coverage even after a shorter hospital stay or one spent under observation status. Always confirm with your plan before assuming you’re covered.
Skilled Nursing Coverage After a Hospital Stay
If you do meet the qualifying stay requirements, Medicare covers up to 100 days in a skilled nursing facility per benefit period. The first 20 days are fully covered. Days 21 through 100 require a daily copay under Original Medicare. After day 100, you’re responsible for all costs.
Medicare Advantage plans must cover at least this same benefit, but their copay structure for skilled nursing days may differ. Some plans charge flat daily copays that are higher or lower than Original Medicare’s rate. The important thing is that the three-day inpatient rule, which is one of the most common barriers to skilled nursing coverage, can potentially be waived by your Advantage plan. Ask your plan directly whether they participate in this waiver before you’re discharged from the hospital.
What to Check Before a Hospital Stay
If you have a planned admission, a few steps can prevent billing surprises. First, confirm that the hospital and your treating physicians are in-network. Second, find out whether your plan requires prior authorization for the admission and make sure your doctor’s office has submitted the request. Third, ask the hospital whether you’re being admitted as an inpatient or placed under observation, because the cost and coverage implications are different.
Finally, review your plan’s Evidence of Coverage document for the specific daily copays and limits that apply to inpatient stays. Every Medicare Advantage plan publishes this document, and it spells out exactly what you’ll owe for each day in the hospital. Hospitals are also now required to post their negotiated charges with Medicare Advantage plans on a public website, giving you another way to estimate costs before a planned procedure.