Observation vs inpatient: the hospital status that changes your Medicare bill
Why being 'under observation' is billed under Part B, how it affects skilled nursing coverage, the MOON notice, and what to ask the hospital.
Two patients can spend the same three nights in the same hospital bed and get very different Medicare bills. The difference is whether the hospital admitted them as an inpatient or kept them as an outpatient under observation.
How each is billed
| Inpatient | Observation (outpatient) | |
|---|---|---|
| Which part of Medicare | Part A | Part B |
| What you pay | $1,736 deductible per benefit period | 20% of each service after the Part B deductible, plus self-administered drugs |
| Counts toward 3-day skilled nursing rule | Yes | No |
The skilled nursing trap
Original Medicare covers skilled nursing facility care only after a qualifying inpatient stay of three days (counting the day of admission, not discharge). Observation days do not count. A patient who spends four nights under observation and then needs rehab can find Medicare will not pay for the nursing facility, leaving bills of hundreds of dollars a day. See the 3-day rule and costs.
The MOON notice
Hospitals must give you a Medicare Outpatient Observation Notice if you are under observation for more than 24 hours. It explains that you are an outpatient and what that means for your costs. Read it.
What to ask
- "Am I an inpatient or under observation?" Ask every day; status can change.
- "Will my stay count toward skilled nursing coverage?"
- If you think you should be inpatient, ask your doctor to explain the decision. Some beneficiaries can appeal observation status under rules adopted after a federal court case.
How Medigap helps
Medigap covers the 20% Part B coinsurance on observation services (fully under Plans like G), but it cannot change Medicare's skilled nursing rules. If Medicare will not pay for the nursing facility, Medigap will not either. The plan letter guide shows which plans cover skilled nursing coinsurance when Medicare does.
Questions people ask
What is observation status?
Outpatient hospital care billed under Part B, even if you stay overnight.
Do observation days count for skilled nursing?
No. Only inpatient days count toward the 3-day rule.
What is the MOON?
A notice hospitals must give after 24 hours of observation explaining your status.
Can I appeal observation status?
Some beneficiaries can; ask the hospital and your State Health Insurance Assistance Program.
Independent educational site. Not affiliated with or endorsed by the U.S. government, the federal Medicare program, or any insurance company. Figures are 2026 amounts published by CMS unless noted; check Medicare.gov for your situation.