When Medicare's 100 Skilled Nursing Days Run Out
A parent falls, spends a few days in the hospital, and goes to a rehab facility afterward. Someone at the hospital says Medicare covers up to a hundred days. The family hears a hundred days and stops worrying about the money for three months.
Then a letter arrives on day nineteen saying coverage is ending.
We see this often enough that it is worth writing down carefully. The hundred days is real, but it is a ceiling under conditions, not an allowance. Almost nobody gets all hundred. The conditions are where families lose money they did not have to lose, and two of them can still be fixed after the fact if you know they exist.
The three day rule, and the word that costs the most
Before Medicare will pay for skilled nursing facility care, there has to be a qualifying inpatient hospital stay of at least three days in a row. The count starts the day your parent is admitted as an inpatient. It does not include the day they leave.
The three days also do not have to run straight into rehab. Medicare still treats the admission as post-hospital if it happens within 30 days of leaving the hospital, or later where it would not have been medically appropriate to start sooner. A family that tries home first and finds within the month that it is not working has usually not lost the benefit.
Here is the part that catches people. Time spent in the hospital under observation, or in the emergency room before being admitted, does not count toward those three days. Not even overnight. Not even if they slept in a hospital bed, wore a hospital gown, and were given medication by a nurse for two full days.
Observation is billed as an outpatient service. To a family standing in the room, an observation stay and an inpatient stay look identical. To Medicare they are different categories, and only one of them opens the door to paid rehab.
This is the single most expensive detail in this article. A parent can spend four nights in a hospital, be discharged to a nursing facility, and owe the entire bill, because the hospital classified the stay as observation.
You can now appeal that classification
This is new enough that most of what is written about observation status has not caught up with it, and it is the reason we would rather you read a careful article than a popular one.
If your parent was admitted as an inpatient and the hospital changed the status to outpatient receiving observation services during the stay, there is now a right to a fast appeal. It comes from a federal rule called "Medicare Program: Appeal Rights for Certain Changes in Patient Status," effective October 11, 2024, after years of litigation on behalf of beneficiaries who had no way to challenge the switch.
The hospital is supposed to give you a Medicare Change of Status Notice, form CMS-10868, before your parent leaves. If you do not get it, ask for it. The notice explains that the stay will be billed to Part B rather than Part A, and it tells you how to reach your state's Beneficiary and Family Centered Care Quality Improvement Organization, which is the body that hears the appeal.
File while your parent is still in the hospital if you possibly can, because the timing changes three things at once. Requested no later than the day of release, the review organization must decide within one calendar day of getting the information it asks for. Requested after that, you still keep the right, but the decision takes two calendar days, and the billing protection that comes with a timely request does not apply. If you cannot find the notice, contact the organization directly rather than waiting for paperwork.
One day is fast enough to change a discharge plan while it is still being written. That is the whole point of filing early.
If this already happened to your family
The same rule created a second, slower route for status changes that happened before the new appeals process started, reaching back to hospital admissions from January 1, 2009. It runs through the ordinary claims appeal chain rather than the fast review: a Medicare Administrative Contractor first, then reconsideration, then an administrative law judge if it goes that far.
There is a catch worth knowing before you spend an afternoon on it. That backward looking route carries a filing window of 365 days from the date the rule was put into operation, and CMS announced that date separately rather than in the rule itself. If a reclassification cost your family money in an earlier year, it is worth one phone call to the review organization to ask whether your window is still open. It is not worth building a plan around until you have asked, and any article that tells you the door is simply open is not accounting for the deadline.
Ask about the waivers, because they are common
The three day requirement is not universal. A doctor participating in an Accountable Care Organization approved for a Skilled Nursing Facility 3-Day Rule Waiver may not need it. Medicare Advantage plans may also waive the three day minimum.
Neither of these will be volunteered while you are standing at a discharge desk. Ask directly whether a waiver applies, and ask before your parent leaves the hospital rather than after.
If there is no qualifying stay and no waiver, ask what else is available. Home health care is a different benefit with different rules, and Medicaid or veterans benefits may reach the situation that Medicare will not.
What it actually costs in 2026
Assume the coverage is approved. Here is the arithmetic, per benefit period.
Days 1 through 20 cost nothing per day, after the Part A deductible of $1,736. If your parent already paid that deductible for the hospital stay in the same benefit period, they do not pay it twice.
Days 21 through 100 cost $217 each day.
That second line is the one to sit with. Eighty days at $217 is $17,360 out of pocket, on a stay that a family was told Medicare covers. Some people have a Medigap policy that picks it up. Many do not, and nobody mentions it in the hospital.
Day 101 onward, Medicare pays nothing toward the stay.
The rule that ends coverage early, and is often applied wrongly
The most common thing we hear is that therapy said the parent had "plateaued" or was "no longer making progress," and coverage ended.
Improvement is not the standard. Medicare's own description of who qualifies says a person needs skilled nursing care or therapy to improve or maintain their current condition, or to prevent or delay it from getting worse.
Maintaining counts. Preventing decline counts. A parent with Parkinson's who will not get better, but who will lose ground quickly without skilled therapy, can meet the standard for skilled care. So can someone recovering from a stroke whose gains have levelled off but whose safety depends on continued skilled attention.
If you are told coverage is ending because your parent has stopped improving, that reason by itself does not match the rule. Say so, calmly, and ask for the decision in writing.
When the notice comes, there is a deadline on it
When coverage is about to end, the facility gives you a Notice of Medicare Non-Coverage. That notice carries a time by which you must request a fast appeal, and the same independent organization reviews it.
Call by the time printed on the notice. Not the next business day, not after you have talked it over with your brother. The deadline is short and it is real, and the appeal is free.
If the reviewer decides services should end, your parent is not responsible for the care given before the coverage end date printed on that notice.
The hundred days can come back
A benefit period begins the day your parent is admitted as an inpatient to a hospital or skilled nursing facility. It ends when they have gone 60 days in a row without inpatient hospital care and without skilled care in a facility.
There is no limit on how many benefit periods a person can have in a year. So a parent who used up eighty days in the spring, then went sixty days at home without skilled care, starts a fresh benefit period with a fresh hundred days and a fresh deductible if they are hospitalized again in the autumn.
Families assume the hundred days is annual, or once in a lifetime. It is neither. It is per benefit period, and benefit periods reset.
What tends to happen at the end
Medicare's skilled nursing benefit is for skilled care after a hospitalization. It was never built to fund long term care, and the gap between what it covers and what a family needs next is where most of the difficult decisions live. We wrote separately about going from a hospital directly into adult foster care in Michigan, which is the path a lot of families in Troy and the rest of Oakland County end up taking.
Two practical things while the clock is still running. Start looking at what comes next around day fifteen, not day ninety, because the good options have waiting lists and the bad decisions get made in a hurry. And ask the facility's social worker for the discharge date in writing as soon as anyone mentions one, because a date on paper is something you can plan against and a date in conversation is not.
Nobody in the hospital is going to walk your family through the three day rule, the observation trap, the appeal you now have a right to, or the fact that maintaining counts. That is not a conspiracy. It is a system with a lot of moving parts and not enough people to explain them. Knowing the four of them puts you ahead of where most families start.