Medicare expanded continuous glucose monitor coverage in 2024, but the rules depend on your diabetes type and which Medicare plan you have

In 2024, Medicare made changes to how it covers continuous glucose monitors (CGMs) — the small devices that track blood sugar throughout the day. The main shift: Medicare Part B now covers CGMs for people with type 2 diabetes who use insulin, not just those with type 1 diabetes. If you have type 2 diabetes and do not use insulin, or if you use a Medicare Advantage plan instead of Original Medicare, the coverage picture is different. Your out-of-pocket costs and which devices are covered also depend on which plan you have and whether you have already met your deductible.

Understanding what changed and who qualifies matters because it affects whether you can get a CGM covered and how much you will pay. The 2024 expansion opened the door for millions of type 2 diabetes patients, but only those using insulin injections. If you are unsure whether you fit the new rules, this guide walks you through the specifics.

Key Takeaways

  • Medicare Part B added coverage for type 2 diabetes patients who inject insulin, a change that took effect in 2024.
  • Type 1 diabetes patients and type 2 patients using insulin remain covered under Part B, but coverage rules and device options vary by plan.
  • Medicare Advantage plans set their own CGM coverage rules, so you need to check your specific plan's formulary to know what is covered.
  • Once you meet your Part B deductible, you typically pay 20 percent of the approved amount for CGM supplies and sensors.
  • Your doctor must document that you meet medical necessity requirements — usually that you check blood sugar multiple times daily or have frequent low blood sugar episodes.

Who is covered for CGMs under Original Medicare Part B

Original Medicare Part B now covers CGMs for two groups: people with type 1 diabetes, and people with type 2 diabetes who use insulin injections. The coverage does not extend to people with type 2 diabetes who manage their condition with oral medications alone, even if their doctor believes a CGM would help them.

Your doctor must document that you meet medical necessity. For type 1 diabetes, this is usually straightforward — the diagnosis itself generally satisfies the requirement. For type 2 diabetes patients using insulin, your doctor needs to show that you inject insulin and that monitoring your blood sugar frequently is medically necessary. This might mean you check your blood sugar multiple times a day, or that you have a history of low blood sugar episodes that are hard to predict.

The specific CGM devices covered under Part B are those on Medicare's approved list. As of 2024, this list includes the Dexcom G6, Dexcom G7, FreeStyle Libre 2, and Medtronic Guardian. Your doctor will need to order the device, and you will work with a supplier that Medicare recognizes. Not every pharmacy or medical supply company can dispense Medicare-covered CGMs, so your doctor or the device manufacturer can help you find an approved supplier in your area.

How costs work under Original Medicare Part B

Once you have met your Part B deductible for the year, Medicare pays 80 percent of the approved amount for your CGM supplies and sensors. You pay the remaining 20 percent. The deductible amount changes each year — in 2024 it was $240, though this figure varies by year.

The "approved amount" is what Medicare decides the device is worth, not necessarily what the manufacturer charges. If your supplier bills more than the approved amount, they cannot charge you the difference — that is called balance billing, and it is not allowed for Medicare-covered items. Your out-of-pocket cost depends on how many sensors you use per month and how often you need replacement transmitters or other supplies.

If you have a Medigap or other supplemental insurance policy, it may cover some or all of your 20 percent coinsurance. Check your policy documents or call your supplemental insurer to see what they cover for durable medical equipment and supplies. Many Medigap plans do cover coinsurance for Part B items, which can significantly reduce what you pay out of pocket.

Medicare Advantage plans and CGM coverage

If you have a Medicare Advantage plan (Part C), your coverage for CGMs is set by your individual plan, not by Medicare Part B rules. Some Medicare Advantage plans cover CGMs for type 1 and type 2 insulin-using patients, while others may have different rules or may not cover them at all. A few plans cover CGMs for type 2 patients on oral medications, but this is less common.

To find out what your Medicare Advantage plan covers, look at your plan's formulary — the official list of covered medications and supplies — or call the plan's customer service number. You can also check the plan's website or ask your doctor's office to contact the plan on your behalf. Because Medicare Advantage plans can change their coverage each year, it is worth checking even if your plan covered CGMs last year.

Your out-of-pocket costs under Medicare Advantage vary by plan. Some plans charge a copay per sensor, others charge coinsurance (a percentage), and some may waive the cost entirely. Your plan documents will spell out what you owe. If your plan covers CGMs, the supplier will verify your coverage and tell you your cost before they send the device.

What changed from 2023 to 2024

The most significant change in 2024 was the expansion of Part B coverage to include type 2 diabetes patients who use insulin. Before 2024, Medicare Part B covered CGMs only for type 1 diabetes patients. This expansion means more people now have a path to Medicare-covered CGM use, though the medical necessity documentation requirement remains.

Device coverage has also shifted slightly as newer models have been added to Medicare's approved list. The Dexcom G7 and FreeStyle Libre 2 became more widely available under Medicare in 2024, giving patients more options than in previous years. However, not all CGM devices on the market are covered — some newer or less common models may not be on Medicare's list yet.

If you were already using a CGM under Medicare before 2024, your coverage should not have changed unless you switched plans or your plan made its own updates. If you are newly interested in a CGM because of the 2024 expansion, talk to your doctor about whether you meet the medical necessity criteria and which approved device might work best for you.

How to start the process with your doctor

If you think you are covered for a CGM under the 2024 rules, the first step is to talk with your doctor — the one who manages your diabetes. Bring up that Medicare now covers CGMs for your situation and ask whether they think one would help you manage your blood sugar. Your doctor will need to write an order that includes documentation of medical necessity.

Once your doctor has written the order, they will either send it to a Medicare-approved supplier or give it to you to take to one. The supplier will verify your Medicare coverage, check that you have met your deductible, and walk you through the setup process. They will also handle the paperwork with Medicare. This process typically takes one to two weeks from the time your doctor places the order.

If your doctor is not familiar with Medicare's CGM coverage rules, you can share this information with them or ask them to contact Medicare directly. Your local Medicare office or a patient advocate at your doctor's office can also help clarify what documentation your doctor needs to provide. Many suppliers also have staff who work with doctors regularly and can guide the ordering process.

What to do if your plan does not cover CGMs

If you have a Medicare Advantage plan that does not cover CGMs, or if you have type 2 diabetes without insulin and do not may have access to for Part B coverage, you have a few options. Some CGM manufacturers offer patient support programs that reduce the cost of devices for people without insurance coverage. Dexcom, FreeStyle, and Medtronic all have programs that may lower your out-of-pocket cost based on your income.

You can also ask your doctor whether there are other ways to monitor your blood sugar that Medicare does cover — for example, traditional blood glucose meters and test strips are covered for all people with diabetes, regardless of type or treatment method. While not as convenient as a CGM, they remain a covered option. Your doctor can help you figure out a monitoring plan that works within your coverage.

If you are in a Medicare Advantage plan and believe a CGM is medically necessary for you, you can file an appeal with your plan. This process varies by plan, but generally involves your doctor submitting a detailed medical justification. Your plan must respond within a set timeframe. If your plan denies the appeal, you have the right to request an independent review through Medicare.

Frequently Asked Questions

Does Medicare cover the reader or transmitter separately from the sensors?

Yes. Medicare covers the reader (the device that displays your blood sugar readings) and the transmitter (the part that sends data wirelessly) as separate items. You may need to replace the transmitter more often than the sensors, depending on the device. Your supplier will order all the parts you need, and Medicare will cover them under the same 80/20 split after your deductible.

Can I use a CGM that is not on Medicare's approved list?

Medicare will not pay for a CGM that is not on its approved list, even if your doctor prescribes it. If you want to use a device that is not covered, you would pay the full cost yourself. Some newer CGM models may be added to Medicare's list over time, so it is worth checking back if your preferred device is not currently covered.

What happens if I switch from Original Medicare to a Medicare Advantage plan mid-year?

Your CGM coverage will change based on your new plan's rules. If your new Medicare Advantage plan covers CGMs, you may be able to continue using your current device, though you should contact the plan to confirm. If the new plan does not cover CGMs or covers different devices, you will need to work with your doctor and the plan to figure out next steps. Coverage changes can take time to process, so start the conversation as soon as you know you are switching.

Do I need prior authorization from Medicare before I order a CGM?

For Original Medicare Part B, your doctor's order and documentation of medical necessity is usually enough — you do not need to request permission from Medicare first. However, your Medicare-approved supplier will verify your coverage before they send the device. If you have a Medicare Advantage plan, check your plan documents or call customer service, because some plans do require prior authorization before you can get a CGM.

If my doctor says I need a CGM but I do not meet Medicare's criteria, what are my options?

You can pay out of pocket, look into manufacturer patient support programs that may reduce your cost, or ask your doctor whether an appeal to your plan is worth pursuing. Some people also check whether they may have access to for state pharmaceutical information programs or nonprofit organizations that help with diabetes supplies. Your doctor's office or a diabetes educator may know about local resources in your area.