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Your Medicare Outpatient Observation Notice, Explained
Also called: MOON
Last reviewed 2026-07-08
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What this notice usually means
The MOON tells a hospital patient they are under observation, not admitted. A hospital must give it within 36 hours of that status starting. This status can change your costs and later nursing home coverage.
What to do now
- 1
Read your status on the MOON
The notice states your status, outpatient under observation or admitted. It also states for how long.
- 2
Ask your care team why
Ask the hospital staff why you are under observation instead of admitted. How it affects your bill.
- 3
Watch for cost sharing differences
Outpatient status can mean different costs than an inpatient stay. Drug coverage rules can differ too.
- 4
Call Medicare with questions
Call 1-800-MEDICARE (1-800-633-4227) with questions. Ask how your status affects coverage.
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“The form notifies Medicare beneficiaries receiving hospital observation services for over 24 hours about their status, cost-sharing implications, and eligibility for skilled nursing facility coverage.”
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Sources
- OMB / reginfo.govRetrieved 2026-07-07
Last reviewed 2026-07-08
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