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.
Questions regarding the MOON can be submitted at: https://appeals.lmi.org