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Letter of Medical Necessity (LMN)

A letter of medical necessity is required when an expense must be substantiated by a written statement from your physician indicating that the treatment expense is necessary for the alleviation or prevention of a physical or psychological illness. Examples include massage therapy, supplements or vitamins, and weight loss programs which would not be eligible without additional substantiation from your physician. Be sure the letter names the specific medical condition being treated with the product or service.

Sentinel will keep a letter of medical necessity on file for 12 months. Each subsequent year you will need to supply a new letter in order for the expenses to continue to be eligible for reimbursement. You only need to submit the letter once during the year.

Since expenses are conditionally eligible, it is likely the Benny Card cannot be used at the point of sale. If the Benny Card is declined, you will need to pay with another form of payment and submit a claim for reimbursement through your online account.

What information should be included?

  1. Patient Name.
  2. A specific diagnosis/treatment needed
    • The recommended treatment must be described by your licensed healthcare provider.
      • For example, a recommended exercise program through a gym membership for the next six months to alleviate the patient's hypertension.
  3. Duration of the treatment
    • A provider may recommend a specific duration of treatment
      • If this is not available, we consider the LMN valid one year from the date it is written.
      • If the treatment extends beyond the stated time period, the member must submit a new LMN covering the new time period.
      • A LMN cannot exceed a 12-month period.
  4. Must be signed by a licensed practitioner.
  5. An acceptable LMN form
    • Sentinel's LMN template
    • Provider's official letterhead
    • A doctor's prescription/LMN written on a prescription pad
    • Discharge papers



Need a form to share with your provider? Download our LMN Template .