You are in a hospital bed. A doctor is treating you. The care looks and feels identical to being admitted. But if you are under observation status rather than inpatient admission, Medicare may not cover the skilled nursing stay you need when you leave. This is one of the most financially damaging surprises in all of Medicare.
Dollar figures reflect 2025 Medicare rates. CMS adjusts these annually. Verify current rates at medicare.gov before making decisions.
Topic one
What observation status actually means
Hospitals classify patients as either inpatient or outpatient. Observation status is an outpatient classification. The problem is that observation patients and inpatient patients can be in identical rooms receiving identical care - and neither the patient nor the family is always told the difference or what it means for the bill.
Inpatient admission
What you want
Formally admitted - covered under Part A
Days count toward 3-day SNF qualifying stay
Prescription drugs administered in hospital covered
Part A deductible applies ($1,676 in 2025)
Observation status
What surprises people
Technically outpatient - even in a hospital bed for days
Zero days count toward the 3-day SNF qualifying stay
Drugs administered may not be covered - billed as outpatient
Billed under Part B with 20% coinsurance on each service
Four nights in the hospital under observation status means zero qualifying inpatient days. Medicare will not cover the SNF stay.
This is the core of why observation status matters so much. The three-night inpatient qualifying requirement for Medicare SNF coverage counts only formal inpatient days - not observation days. A patient can spend an entire week in a hospital bed under observation, be transferred to a skilled nursing facility, and find that the entire SNF stay is uncovered by Medicare. In 2025, a skilled nursing facility stay costs $400 to $700 per day private pay when Medicare is not covering it.
Topic two
What it actually costs
The financial impact of observation status is real and large. Here is what a typical scenario looks like.
Example scenario - 2025 rates
3-night observation stay followed by 20-day SNF stay
In-hospital drugs billed as outpatient (Part D or out-of-pocket)Varies widely
20-day SNF stay not covered (no qualifying inpatient stay)$8,000 - $14,000
Total estimated out-of-pocket$10,000 - $18,000+
Compare - same stay, inpatient admission
3-night inpatient stay followed by 20-day SNF stay
Hospital stay - Part A deductible (2025)$1,676
SNF days 1 through 20 - fully covered under Part A$0
Total estimated out-of-pocket$1,676
Medigap Plan G does not help with observation status. The SNF gap is the issue, not the coinsurance.
Medigap Plan G covers the 20% Part B coinsurance during an observation stay and covers the SNF daily coinsurance for days 21 through 100. What it cannot do is create a qualifying inpatient stay that does not exist. If there is no qualifying 3-night inpatient stay, there is no Medicare SNF coverage to supplement. Plan G cannot fill a gap that starts with a coverage determination, not a cost-sharing gap.
Topic three
The two-midnight rule
CMS established the two-midnight rule in 2013 to clarify when inpatient admission is appropriate. Understanding it helps you and your physician make the case for inpatient status when it is clinically justified.
The two-midnight rule says inpatient admission is appropriate when a physician reasonably expects the patient to need hospital care spanning at least two midnights.
The key word is "expects" - the determination is made based on the physician's clinical judgment at the time of admission, not in retrospect. If the physician expects the patient will need hospital-level care for at least two midnights, inpatient admission is appropriate regardless of how long the patient actually stays. A patient who improves faster than expected and leaves after one midnight can still have been correctly classified as inpatient based on the physician's reasonable expectation at admission.
The two-midnight rule does not mean you automatically get inpatient status after two nights.
The rule establishes the standard for when inpatient admission is appropriate - it does not guarantee it. A utilization review nurse or insurance reviewer can still determine that inpatient criteria were not met even after two midnights have passed. The expectation must be documented in the medical record at the time of admission. If the physician's notes do not support an expectation of two-midnight care, the status may remain as observation even if the patient stayed longer.
The attending physician has the authority to change an observation status to inpatient if they believe the clinical situation meets the two-midnight criteria. The conversation to have is direct: "I understand I am currently under observation status. Based on my condition, do you believe my care is expected to require at least two midnight stays? If so, can you document that expectation and submit an inpatient admission order?"
The physician may say yes and change the order. They may say the clinical situation does not meet the threshold. They may refer the decision to the utilization review team, which is also appropriate - you can then ask to speak with the utilization review nurse directly.
The important thing is to ask early - ideally within the first 24 hours - and to ask in a way that puts the clinical question to the physician rather than the billing question. "Does my condition justify inpatient admission?" is a clinical question. That is the right framing.
If the status is not changed and you believe it should be, the formal appeal path is through the BFCC-QIO. See the appeal section below.
Topic four
The MOON notice
Hospitals are legally required to notify you in writing when you are under observation status for more than 24 hours. This notice is called the Medicare Outpatient Observation Notice.
If you receive a MOON notice, the hospital is telling you something important: your stay will not count toward Medicare SNF eligibility.
The MOON must be delivered and explained to you within 36 hours of being placed under observation status for more than 24 hours. It explains that you are an outpatient, what that means for your costs, and that Medicare will not cover a subsequent skilled nursing stay based on this hospitalization alone. Receiving it is your signal to act - ask about reclassification, and know your appeal rights before you need them.
You must sign the MOON, but signing does not mean you agree with the classification.
The MOON requires your signature to acknowledge that you received and understood it. Signing does not waive your right to appeal or request reclassification. If you are asked to sign the MOON, you can write "received under protest" next to your signature if you intend to pursue reclassification. Keep a copy of the signed notice with your paperwork.
Topic five
How to appeal
You have the right to appeal an observation status classification. The appeal goes to the BFCC-QIO for your region. Here is how the process works.
1
Contact your BFCC-QIO as soon as possible
The phone number is on your MOON notice. You can also call 1-800-MEDICARE (1-800-633-4227) to be connected to the right QIO for your state. For a hospital stay you are still in, you must contact the QIO no later than noon the calendar day after you receive a notice that Medicare will not cover your stay.
2
The QIO requests your medical records from the hospital
Once you file a request, the QIO notifies the hospital and requests your clinical record. The hospital must cooperate with this process. You will have the opportunity to provide a written statement supporting your case, which the QIO is required to consider.
3
The QIO issues an independent determination
The QIO reviews the clinical record and determines whether the care met the criteria for inpatient admission. This typically happens within one to two business days. If the QIO agrees the stay should have been inpatient, the classification can be changed retroactively. If the QIO upholds the observation classification, you can appeal further.
4
If denied, formal written appeal levels remain available
If the QIO rules against you, formal written appeal levels include a Qualified Independent Contractor (QIC), then an Administrative Law Judge, then the Medicare Appeals Council, then federal district court. Each level has specific timelines. A SHIP counselor can guide you through these levels at no charge - find yours at shiphelp.org.
Appealing an observation classification after you have already left the hospital is harder but still possible.
The fastest and most effective time to appeal is while you are still in the hospital. Once you leave, the process involves a formal written appeal rather than the expedited QIO review. You can still pursue this - some patients have successfully obtained retroactive reclassification after discharge - but the timeline is longer and the documentation requirements are more demanding. If you realize after discharge that you were under observation status, contact a SHIP counselor to evaluate whether a retroactive appeal is viable.
Topic six
What happens after discharge
If your observation status appeal was unsuccessful or you did not appeal, here is what your options look like for the skilled nursing stay.
Medicare will not cover the skilled nursing stay without a qualifying 3-night inpatient hospitalization. Your options are:
Medicaid: If you qualify for Medicaid, the 3-night qualifying stay requirement does not apply to Medicaid-covered SNF care. Medicaid can cover a skilled nursing stay that Medicare will not. Eligibility and benefits vary by state. If you think you may qualify, contact your state Medicaid agency or a SHIP counselor immediately.
Private pay: You can pay for the SNF stay out of pocket. SNF rates vary widely - ask the facility for their current daily rates for private-pay patients and for Medicare-covered rates (which gives you a reference point). Ask about any financial assistance programs they have for patients who are not covered by insurance.
Home with home health: If your clinical needs can be safely managed at home with Medicare-covered home health visits, this may be an option even without a qualifying inpatient stay. Home health does not require a prior hospital stay - it requires a physician order, homebound status, and a skilled care need. Discuss with your physician whether home health is a viable alternative to the SNF.
Medigap Plan G or other supplement: Your supplement may cover Part B coinsurance from the observation stay itself, but it cannot create Medicare SNF coverage that does not exist due to the missing qualifying stay. It will help with the hospital bill but not the SNF bill.
Ask about admission status every time someone is admitted to a hospital. The question is simply: "Is this an inpatient admission or observation status?" Ask at admission and ask again if the stay extends or if the clinical situation changes. Ask the nurse, ask the hospitalist, ask the case manager.
If the answer is observation, ask the attending physician whether the clinical situation justifies the two-midnight expectation for inpatient admission. Bring this up early - in the first 24 hours - when there is still time to change the classification before discharge planning begins.
Keep a copy of any MOON notice you receive. Document when you asked about status and what you were told. This record is valuable if you later appeal.
About the figures on this page.
Dollar amounts and program thresholds reflect published 2025 rates from the Centers for Medicare & Medicaid Services (CMS) and the Social Security Administration (SSA). CMS adjusts most figures annually, typically in the fall before each coverage year. Verify current rates at
medicare.gov
or
ssa.gov
before making enrollment or coverage decisions.
Project Kos is an educational resource. Nothing on this page is legal, financial, or medical advice.
