Letter of Medical Necessity

A letter of medical necessity (LOMN)is an important part of obtaining services, treatments, medications and medical devices for patients.

Whether in response to a denial or as an initial request for funding or reimbursement, a properly completed LOMN makes clear the necessity of a particular medical intervention for a patient to an insurance company or other funding source.

The letter should be written by a healthcare professional who has provided care to the patient and is familiar with the patient's condition and needs. As the sample below details, a letter of medical necessity should follow a standard template to clearly identify who is making the request on behalf of the patient and their qualifications to do so, current patient condition and diagnoses, patient history and past services and treatments and justification for the newly-requested medical care and the desired outcome.

If the medical professional requesting the services is not a physician, the LOMN should be endorsed by the patients's physician or accompanied by a physician's prescription.

Sample Letter of Medical Necessity

The letter should be written on official letterhead with complete contact details.

Patient name


Prescribing physician

Medical diagnoses & ICD-9 codes

Requested medical service

Date of assessment

Detail the patient's diagnoses.

Provide a brief background of the patient's medical history, including past treatments/medications/equipment.

Specify the requested treatment/medication/equipment, what it will address and the desired outcome.

Explain why the requested treatment/medication/equipment is medically necessary and why it is the best option.

Summarize the letter and emphasize the logical conclusion.

Medical professional's name, title and signature.