Completion of Certifications of Medical Necessity - Annual Reminder

Joint DME MAC Publication

Dear Physician:

Certificates of Medical Necessity, commonly known as CMNs, are documents used by the DME MACs to assist in gathering information about the medical necessity of an item. It is your responsibility to determine both, the medical need for, and the utilization of, all healthcare services.

Suppliers of durable medical equipment, prosthetics, orthotics and supplies (DMEPOS) are your partners in caring for your patient. They will not receive payment for their services until you return the completed, signed and dated CMN. If you have ordered equipment or supplies as part of your patient's treatment plan, completing the CMN accurately and in a timely manner helps insure that your treatment plan will be carried out. Moreover, your cooperation is a legal requirement as outlined in the Social Security Act, the law governing Medicare. Section 1842(p) (4) of the Act provides that:

[i]n case of an item or service…ordered by a physician or a practitioner…but furnished by another entity, if the Secretary (or fiscal agent of the Secretary) requires the entity furnishing the item or service to provide diagnostic or other medical information in order for payment to be made to the entity, the physician or practitioner shall provide that information to the entity at the time that the item or service is ordered by the physician or practitioner.

Printable copies of CMNs and DIFs are available on the CMS website at To find the CMN/DIF you are looking for, enter the name or form number in the "Filter On" field. For instance, if you are searching for the Oxygen CMN, enter the word "oxygen" or "484".

Remember, everyone has tight cash flow these days – help your DMEPOS supplier continue good service to your patients by prompt completion and return of the CMN.


Peter J. Gurk, M.D.


Last Updated Thu, 19 Dec 2019 10:20:16 +0000