Medicare covers several continuous glucose monitors (CGMs) under Part B as durable medical equipment, including devices from Dexcom, Abbott, and the Eversense implantable system. Coverage isn’t automatic, though. You need to meet specific medical criteria, get a prescription, and use a supplier that participates in Medicare’s DME program.
CGM Devices Medicare Covers
Medicare splits CGM coverage into two categories: standard wearable CGMs and implantable CGMs, each governed by separate coverage policies.
For wearable CGMs, the major devices currently available to Medicare beneficiaries include the Dexcom G7, the Abbott FreeStyle Libre 2 and FreeStyle Libre 3, and the Dexcom G6 (though most new prescriptions now use newer models). These are the sensor-and-transmitter systems you wear on your skin, typically on the back of your upper arm or abdomen, and replace every 10 to 15 days depending on the model.
For implantable CGMs, the Eversense E3 is currently the only FDA-cleared device in this category. It’s a small sensor placed under the skin by a healthcare provider and lasts up to six months before needing replacement. Medicare covers this under a separate policy (LCD L38617) with its own set of rules.
Who Qualifies for Coverage
Medicare doesn’t cover CGMs for everyone with diabetes. You need to meet at least one of two main clinical criteria. The first and most common path: you’re treated with insulin. If you take insulin in any form, whether by injection or pump, you qualify on that basis alone.
The second path covers people who aren’t on insulin but have a documented history of dangerous low blood sugar episodes. Specifically, you need one of the following on your medical record:
- Recurrent level 2 hypoglycemia: more than one episode where your blood sugar dropped below 54 mg/dL, despite multiple attempts to adjust medications or change your treatment plan
- One level 3 hypoglycemic event: a single episode where your blood sugar fell below 54 mg/dL and you experienced altered mental or physical functioning severe enough that someone else had to help treat you
In both cases, your doctor must also have prescribed the CGM specifically to improve your blood sugar control, and you (or a caregiver) must have received sufficient training on how to use the device.
The Required Doctor Visit
Before your doctor can order a CGM, Medicare requires an in-person visit or a Medicare-approved telehealth appointment within six months before the order is placed. During that visit, your doctor needs to evaluate your diabetes management and confirm you meet the coverage criteria. This isn’t just a formality. The visit must be documented in your medical record, and the notes need to reflect that your provider assessed your glycemic control and determined a CGM is appropriate.
For ongoing coverage, the rules differ slightly by device type. For implantable CGMs like the Eversense E3, you need a follow-up visit every six months where your provider documents that you’re actually using the device and sticking with your diabetes treatment plan. Wearable CGMs have similar ongoing documentation expectations, though the specifics are outlined in your local Medicare contractor’s policies.
What You’ll Pay Out of Pocket
CGMs fall under Medicare Part B as durable medical equipment. After you meet your annual Part B deductible, you pay 20% of the Medicare-approved amount for the device and its supplies (sensors, transmitters, and receivers). Your supplier bills Medicare directly for the remaining 80%.
One important detail: if your DME supplier participates in Medicare, they must accept assignment. That means they can only charge you the 20% coinsurance plus any remaining deductible. They cannot bill you extra above the Medicare-approved price. If a supplier doesn’t participate in Medicare or refuses to accept assignment, you could end up paying significantly more. Always confirm your supplier’s Medicare participation status before placing an order.
If you have a Medigap (Medicare Supplement) plan, it may cover some or all of that 20% coinsurance. Medicare Advantage plans also cover CGMs but may have different supplier networks and cost-sharing structures, so check with your specific plan.
Implantable CGM Coverage Rules
The Eversense E3 has its own separate coverage determination because the device works differently from wearable sensors. It’s surgically inserted under the skin and stays in place for months rather than days. Medicare considers it medically reasonable and necessary when you meet all four of these conditions: you have diabetes, your doctor has confirmed you’re trained on the device, the device is prescribed in line with its FDA-cleared uses, and you meet either the insulin-treated criterion or the problematic hypoglycemia criterion described above.
One notable restriction: Medicare will not cover implantable CGMs for short-term use lasting 72 hours to one week. The device is designed for continuous, long-term monitoring, and that’s how Medicare expects it to be used. The insertion and removal procedures are also covered, since they require a healthcare provider’s involvement.
Part B vs. Part D
CGMs are classified as durable medical equipment under Medicare Part B, not as a pharmacy benefit under Part D. This distinction matters because it affects where you get the device and how billing works. Under Part B, you’ll typically order sensors and supplies through a DME supplier rather than picking them up at a retail pharmacy. Some Medicare Advantage plans may handle this differently, potentially allowing pharmacy pickup, but Original Medicare routes CGMs through DME channels.
This also means CGMs aren’t subject to Part D formulary restrictions or the coverage gap (sometimes called the “donut hole”). Your cost structure follows the straightforward Part B model: deductible first, then 20% coinsurance on the approved amount.
How to Get Started
The process begins with your doctor. Schedule a visit specifically to discuss CGM use, since Medicare requires that documented evaluation within six months of the order. Your provider will need to confirm your diagnosis, verify that you meet at least one of the qualifying criteria, and write a prescription specifying the device.
From there, your doctor’s office typically coordinates with a DME supplier. Some CGM manufacturers also have dedicated teams that help with Medicare paperwork. The supplier will verify your Medicare eligibility, process the prior authorization if needed, and ship the device and sensors to you. Initial orders usually include the receiver or starter kit along with a 30-day supply of sensors. Refill orders for sensors and transmitters follow on a regular schedule, and your supplier should handle reorders as long as your prescription and documentation stay current.