What Medicare Part B covers for continuous glucose monitors
Medicare Part B covers continuous glucose monitors (CGMs) for people with diabetes who meet specific requirements. The devices currently covered are the FreeStyle Libre, Dexcom G6, Dexcom G7, and Guardian 4. Coverage is not automatic — your doctor must prescribe the monitor, and you must have diabetes that requires insulin or certain other medications.
The exact coverage rules changed in 2023 when Medicare expanded access beyond insulin users. Today, Part B covers CGMs for people using insulin multiple times daily, people using intensive insulin management, and people with a history of severe hypoglycemia (dangerously low blood sugar). Your doctor determines whether you fit one of these categories.
Medicare Part B pays 80 percent of the approved amount after you meet your annual deductible. You pay the remaining 20 percent, plus any difference between what Medicare approves and what the manufacturer charges. The actual out-of-pocket cost depends on your specific plan and the device you choose.
Key Takeaways
- Medicare Part B covers FreeStyle Libre, Dexcom G6, Dexcom G7, and Guardian 4 for people with diabetes who use insulin or meet other specific medical criteria.
- Your doctor must prescribe the CGM and confirm you meet Medicare's coverage requirements — you cannot order one on your own.
- You pay 20 percent of the approved cost after your deductible, plus any amount above Medicare's approved price.
- Coverage rules and approved devices can change, so check with your doctor or Medicare directly before purchasing.
How to learn about your doctor can prescribe a covered CGM
Start by talking to your endocrinologist or primary care doctor about whether a CGM makes sense for your diabetes management. Tell them you want to know if Medicare will cover it. Your doctor's office usually handles the paperwork — they submit a request to Medicare that includes your medical history, current medications, and blood sugar records.
Medicare reviews this request and sends a decision letter to your doctor. The process typically takes one to two weeks. If Medicare approves it, your doctor can then write a prescription, and you can order the device from a supplier that accepts Medicare.
If your doctor is unsure whether you meet the requirements, you can call Medicare directly at 1-800-MEDICARE (1-800-633-4227) and ask. Have your diabetes medications and recent blood sugar readings available when you call.
The four devices Medicare currently covers
FreeStyle Libre uses a small sensor worn on the back of your arm that you scan with a reader or smartphone. The sensor lasts 14 days. Medicare covers the sensors and the reader if you have one.
Dexcom G6 is a wearable sensor about the size of a quarter that sends readings to your phone or a separate receiver every five minutes. The sensor lasts 10 days. You need a new sensor every 10 days, so Medicare covers the cost of roughly three sensors per month.
Dexcom G7 is Dexcom's newer model with a 10-day sensor that is smaller than the G6 and connects directly to your phone. It also sends readings every five minutes. Medicare covers this device the same way it covers the G6.
Guardian 4 is made by Medtronic and works with Medtronic insulin pumps or as a standalone device. The sensor lasts seven days and sends readings every five minutes to your phone or receiver. If you use a Medtronic pump, the Guardian 4 integrates with it to pause insulin delivery if your blood sugar drops too low.
What happens after Medicare approves your device
Once you have a prescription and Medicare approval, you order the CGM from a Medicare-approved supplier. Common suppliers include Dexcom's own ordering system, Byram Healthcare, and other DME (durable medical equipment) suppliers. The supplier verifies your Medicare coverage and processes your order.
Your first shipment usually arrives within one to two weeks. The supplier sends you the initial sensors or readers you need to start. After that, you receive refills on a schedule — typically every 30 days for sensors, depending on which device you use.
You pay your 20 percent coinsurance at the time you order, unless you have a Medigap or Medicare Advantage plan that covers additional costs. Some plans cover the full 20 percent; others cover part of it. Check your plan documents or call your plan's customer service to find out what you owe.
What to do if your device is not on the covered list
If your doctor recommends a CGM that Medicare does not cover — such as Eversense or older Dexcom models — you have a few options. You can pay out of pocket for the device and supplies, which typically costs several hundred dollars per month depending on the brand. Some manufacturers offer patient information programs that reduce the cost if you meet income requirements.
You can also ask your doctor whether switching to a covered device would work for your diabetes management. Sometimes a covered device is nearly as effective as an uncovered one, and the cost difference makes it worth considering.
If you believe Medicare should cover a device your doctor prescribed, you can file an appeal. Your doctor's office can help with this. The appeal process takes several weeks, and approval is not certain, but it is an option if you have a strong medical reason for needing a specific uncovered device.
How coverage differs between Medicare Advantage and Original Medicare
Original Medicare Part B covers the four devices listed above at 80 percent after your deductible. You pay 20 percent coinsurance for the approved amount, plus any amount above the approved price.
Medicare Advantage plans (Part C) set their own coverage rules. Some Advantage plans cover the same four devices with different cost-sharing — for example, a flat copay instead of coinsurance. Other Advantage plans may cover additional devices or have different approval processes. A few Advantage plans do not cover CGMs at all.
Check your specific Advantage plan's formulary or call the plan's customer service to find out what CGMs are covered and what you will pay. Do not assume your Advantage plan covers the same devices as Original Medicare.
Frequently Asked Questions
Do I have to use the same CGM brand forever once Medicare approves it?
No. Your doctor can prescribe a different covered device at any time. Medicare will review the new prescription the same way it reviewed the first one. You might switch brands if a new device becomes available, if your current device is not working well for you, or if your medical needs change.
What if I want a CGM but my doctor says I do not meet Medicare's requirements?
You can pay for the device out of pocket, or you can ask your doctor to submit an appeal to Medicare explaining why you need one despite not meeting the standard criteria. Some people with type 2 diabetes or those not using insulin have successfully appealed. The outcome depends on your specific situation and medical records.
Does Medicare cover the training to use a CGM?
Medicare covers diabetes self-management training (DSMT) separately from the device itself. Your doctor can refer you to a certified diabetes educator who teaches you how to use your CGM, understand the readings, and adjust your diabetes care. This training is covered under Part B, though you still pay 20 percent coinsurance after your deductible.
Can I switch to a different covered device if I am unhappy with mine?
Yes. Talk to your doctor about your concerns. If the device is not working well for your lifestyle or your skin is reacting to the adhesive, your doctor can prescribe a different covered device. Medicare will review the new prescription, and you can switch once it is approved.
What if Medicare denies my request for a CGM?
You receive a denial letter explaining why. You can ask your doctor to appeal the decision by submitting additional medical information — for example, recent blood sugar logs showing you need closer monitoring. The appeal process takes several weeks. If Medicare denies the appeal, you can request a hearing before an administrative law judge, though this is rare for CGM coverage decisions.