Medicare Outpatient Observation Notice (MOON)

Hospitals and CAHs are required to provide a MOON to Medicare beneficiaries (including Medicare Advantage health plan enrollees) informing them that they are outpatients receiving observation services and are not inpatients of a hospital or critical access hospital (CAH).  

Full instructions are available in Section 400, of Chapter 30 of the CMS Claims Processing Manual, available at: /Regulations-and-Guidance/Guidance/Manuals/Downloads/clm104c30.pdf (PDF)

Frequently asked questions ("MOON FAQs") are also available under "Downloads" below.

UPDATE - New Medicare Outpatient Observation Notice (MOON):

April 6, 2020: Hospitals are strongly encouraged to begin using the new Medicare Outpatient Observation Notice (MOON) as soon as possible, but no later than May 1, 2020.

January 7, 2020: The Office of Management and Budget (OMB) has renewed the MOON (CMS-10611).  Please note the MOON is unchanged from its current version and only the expiration date is different on this renewed notice. 

The notice, in English and Spanish, is available below under “Downloads.”


Questions regarding the MOON can be submitted at:

Page Last Modified:
04/06/2020 02:58 PM