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)

To download the MOON and instructions, please click on the appropriate link below in "Downloads".

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


December 3, 2019: The currently available MOON has an expiration date of December 31, 2019. This notice is now going through the Paperwork Reduction Act clearance process. The currently available MOON is covered under an extension and hospitals should continue using the current notice until CMS publishes the updated notice. Hospitals following this direction are fully compliant with our requirements.


Questions regarding the MOON can be submitted at:

Page Last Modified:
12/03/2019 02:09 PM