A Continuous Glucose Monitor (CGM) is a wearable device that tracks glucose levels in the interstitial fluid beneath the skin throughout the day and night. This technology provides real-time data and trend arrows, offering a more complete picture of glucose fluctuations than traditional finger-stick tests. Medicare coverage for these advanced monitoring systems has evolved from highly restrictive criteria to a more expansive policy that now includes a greater number of Type 2 Diabetes (T2D) patients.
Current Medicare Coverage Status for Continuous Glucose Monitors
Medicare, specifically through its Part B Medical Insurance program, covers Continuous Glucose Monitors as Durable Medical Equipment (DME). This classification dictates the payment structure and the necessary steps for obtaining the device and its supplies. Historically, coverage was primarily limited to individuals with Type 1 Diabetes or T2D patients who used insulin multiple times daily.
The Centers for Medicare & Medicaid Services (CMS) has significantly expanded this policy to improve access for a broader population of people with diabetes. This expansion recognized that a CGM can be medically necessary even for some T2D patients who do not use insulin. The device and its required supplies, such as sensors and transmitters, are now covered if the patient meets specific criteria established by CMS.
The current policy ensures that the CGM system is covered when used in accordance with the Food and Drug Administration (FDA) indications. Coverage includes both therapeutic CGMs, which can be used to make immediate treatment decisions, and some adjunctive CGMs. The coverage is determined by the patient’s clinical need and risk factors, not just their insulin regimen.
Specific Eligibility Criteria for Type 2 Diabetes Patients
To qualify for CGM coverage under Medicare Part B, a T2D patient must have a diagnosis of diabetes mellitus and meet at least one of two clinical criteria to establish medical necessity. The first qualification is that the patient is currently treated with insulin, regardless of the frequency or type of insulin administration.
The second path to eligibility is for T2D patients who do not use insulin but have a history of problematic hypoglycemia. This is defined by CMS as experiencing recurrent Level 2 hypoglycemic events (glucose levels below 54 mg/dL) that persist despite multiple attempts to adjust medications. Alternatively, a patient qualifies if they have had at least one Level 3 hypoglycemic event, characterized by an altered mental or physical state requiring assistance from another person to recover.
The treating practitioner must confirm that the patient, or their caregiver, has sufficient training to use the prescribed CGM system. This training is intended to ensure the patient can effectively utilize the data for self-management or to adjust their medication regimen. Crucially, the patient must have an in-person or Medicare-approved telehealth visit with the prescribing doctor within six months prior to the order to evaluate their diabetes control and confirm they meet the required criteria.
The physician’s documentation must detail how the patient meets these requirements for the claim to be approved by Medicare. For continued eligibility, the patient must have follow-up visits with the prescribing practitioner at least every six months to assess their adherence to the CGM regimen and diabetes treatment plan. The requirement for frequent finger-stick testing is no longer a mandatory criterion for coverage.
Navigating the Prescription and Supply Process
Once a T2D patient meets the clinical eligibility requirements, the next step is obtaining a prescription, or order, from the treating physician. This order must clearly specify the CGM system being prescribed and confirm that the patient will use the device in accordance with the FDA’s approved indications. The process requires careful coordination between the patient, the doctor, and the supplier.
The CGM system and its subsequent supplies must be obtained through a Durable Medical Equipment (DME) supplier that is enrolled in Medicare. The supplier is generally responsible for submitting the initial claim and handling the necessary paperwork and prior authorization requests to Medicare. Patients should confirm the supplier is Medicare-enrolled to ensure the devices will be covered.
It is important to determine if the selected supplier accepts “assignment,” which means they agree to accept the Medicare-approved amount as full payment. If the supplier does not accept assignment, the patient may be required to pay the full cost upfront and then wait for Medicare to reimburse the covered portion. If an initial claim is denied, the patient has the right to appeal the decision, often with assistance from the prescribing physician or the DME supplier.
Understanding Patient Cost Sharing and Coverage Types
CGM systems and their supplies are covered under Medicare Part B, meaning beneficiaries are subject to standard Part B cost-sharing rules. After the patient meets their annual Part B deductible, they are responsible for a 20% co-insurance of the Medicare-approved amount for the device and its supplies. Medicare pays the remaining 80% of the approved cost.
This cost structure applies to the CGM device, the transmitter, and the disposable sensors. CGMs are covered under Part B and are not covered under Medicare Part D, the prescription drug coverage plan. This distinction is important for understanding where to obtain the supplies and how the costs are billed.
Patients with supplemental insurance, such as a Medigap policy or a Medicare Advantage (Part C) plan, may have their out-of-pocket costs reduced or eliminated. Medigap plans often cover the 20% co-insurance amount. Medicare Advantage plans must provide at least the same coverage as Original Medicare, but they may offer additional benefits or different co-payment structures.