The short answer: Under Medicare, "observation" is outpatient care, even if your parent is in a hospital bed for several nights. It matters because Original Medicare generally covers a skilled nursing facility (rehab) stay only after at least three consecutive days as an admitted inpatient. Days under observation do not count toward those three days. Ask the case manager early: "Is my parent inpatient or observation, and since when?"
What is the difference?
Inpatient means a doctor has formally admitted your parent to the hospital. Hospital costs fall under Medicare Part A.
Observation means the hospital is still deciding whether to admit. It is billed as outpatient care under Part B, which usually means a coinsurance for each service and possibly charges for some medications given in the hospital.
The room, the bed and the care can look exactly the same. The paperwork is what differs.
Why does it matter so much?
- Rehab coverage. To cover a skilled nursing facility stay, Original Medicare generally requires a qualifying inpatient stay of at least three consecutive days, not counting the day of discharge. Observation days do not count.
- Out-of-pocket costs. Outpatient charges under Part B work differently from the Part A inpatient deductible.
Medicare Advantage plans set their own rules and some waive the three-day requirement, so call the plan and ask.
What notices should we receive?
- Medicare Outpatient Observation Notice (MOON). If your parent receives observation services for more than 24 hours, the hospital must give this notice explaining that they are an outpatient and what that may mean for costs.
- Medicare Change of Status Notice. If your parent was admitted as an inpatient and the hospital later changed the status to outpatient observation during the same stay, the hospital should give this notice before discharge.
Can we appeal observation status?
Since February 14, 2025, people with Original Medicare who were admitted as inpatients and then changed to outpatient observation during the same hospital stay have the right to a fast appeal. File with the Beneficiary and Family Centered Care Quality Improvement Organization (BFCC-QIO) listed on the notice. It is best to file while still in the hospital, but you can appeal after leaving. The QIO generally decides in about two days.
If the appeal succeeds, the stay is treated as inpatient, and your parent may qualify for covered skilled nursing facility care if it starts within 30 days of discharge. If it does not succeed, Part B outpatient costs apply.
If your parent was never formally admitted, this particular appeal does not apply, but you can still ask the doctor whether inpatient admission is appropriate and why.
What should I ask, and when?
- On day one: "Is my parent inpatient or observation?"
- Every day after: "Has the status changed?"
- Before discharge: "Will my parent need rehab, and will Medicare cover it given their status?"
- If the status changed: "May I have the Medicare Change of Status Notice and the QIO’s phone number?"
Write down every answer with the date and the name of the person you spoke to. The Hospital Discharge Planning Kit includes a status tracker, the 22 questions to ask before discharge and appeal scripts. If you are worried the discharge itself is too soon, read how to appeal a hospital discharge under Medicare.
Common questions
Can the hospital change status after admission?
Yes, in some cases, which is why the Change of Status Notice and the appeal right exist.
Does the emergency room time count?
Time in the emergency room before a formal admission order generally does not count toward the three inpatient days.
Does this apply to Medicare Advantage?
Medicare Advantage plans have their own coverage rules and appeal processes. Call the plan’s member services number on the back of the card.
Tend & Keep Field Guide. Reviewed October 2026. Educational information, not legal or medical advice. Confirm details with your plan, the QIO on your notice, or 1-800-MEDICARE.