Continuous glucose monitors (CGM): a plain guide for people with Medicare
How a glucose monitor works and who Medicare covers. See what you pay in your ZIP code. Then see how Dexcom, Libre, MiniMed and Eversense differ.
Written by PlanScout teamReviewed by PlanScout Internal Review TeamLast reviewed Oct 25, 202612 sourcesHow we make money
- A continuous glucose monitor (CGM) is a small sensor you wear on your body. It checks your blood sugar day and night and sends the numbers to a phone or reader.[1]
- A fingerstick test shows one moment. A CGM shows the trend, so you can see where your sugar is heading.[2]
- Medicare Part B can help pay for one if you have diabetes and meet its rules. Below we explain those rules, what you pay, and how the main brands differ.[1],[3]
How a CGM works
- A thin sensor sits just under your skin. It reads sugar in the fluid around your cells, not in your blood.[2]
- That fluid can lag behind your blood when your sugar is changing fast. So a CGM number and a fingerstick number can differ for a while.[2]
- If a reading doesn't match how you feel, check with a fingerstick meter before you act on it.[2],[4]
Will Medicare cover it?
- Medicare covers a CGM under Part B when you have diabetes and you either use insulin or have had serious low blood sugar.[3],[1]
- Your doctor must see you, in person or by an approved video visit, in the six months before ordering it. Then every six months after.[3]
- Insulin pills do not exist. Taking diabetes pills alone does not count as using insulin.[3]
What you'll pay
Medicare prices and suppliers near you
With Original Medicare you pay 20% of the Medicare-approved amount after the Part B deductible, if your supplier accepts assignment.
Enter your ZIP code in the price box above to see how many suppliers near you billed Medicare for CGM. Or search suppliers by ZIP.
Go deeper
- Does Medicare cover a CGM? Who qualifies, step by stepThe five Medicare rules in plain words. How you can qualify without insulin. And the visit you need every six months to keep it.
- What a CGM costs with MedicareWhat you pay with Original Medicare. What the monthly supply payment buys. And why using only your phone can cost you.
- How to get a CGM, and how to switch brandsWho writes the order, how to pick a supplier, what training to expect, and what to know before you switch to another CGM brand.
- Living with a CGM: phones, accuracy, travel and fixesHow readings reach your phone or reader, what accuracy numbers mean, airport screening, medical scans and what to do when a sensor fails.
The makers
- DexcomDexcom G7, Dexcom G7 15 Day and Dexcom G6: wear time, warm-up, ages and Medicare notes from Dexcom's own pages.
- FreeStyle LibreAbbott's FreeStyle Libre 3 Plus and Libre 2 Plus sensors: 15-day wear, warm-up, ages, readers and MRI notes from Abbott's own pages.
- MiniMed (Medtronic)Simplera Sync and Guardian 4 sensors for the MiniMed 780G insulin pump, and the Simplera CGM, from Medtronic's own announcements.
- EversenseEversense 365, the implanted sensor a provider places under the skin for up to a year: wear time, calibration and ages from Senseonics.
Differences that matter
Facts from each maker, side by side. This is not a ranking. Your doctor decides what fits you.
| What | Dexcom | FreeStyle Libre | MiniMed (Medtronic) | Eversense |
|---|---|---|---|---|
| Wear time [4],[9],[2],[8],[7] | G7: 10 days + 12 hours. G7 15 Day: 15 days + 12 hours | Libre 3 Plus and 2 Plus: 15 days | Simplera Sync: 6 days + 24 hours | 365: up to 1 year |
| Warm-up [4],[9],[10],[11] | G7: 30 minutes. G7 15 Day: 60 minutes | 60 minutes | Not in the sources we checked | Not in the sources we checked |
| When you still need a fingerstick [4],[2],[12],[7] | When readings don't match symptoms | When readings don't match symptoms | Manual mode, starting SmartGuard, or a mismatch | Weekly calibration after day 14, or a mismatch |
| Approved ages [4],[9],[2],[8],[7] | G7: 2+. G7 15 Day: 18+ | Plus sensors: 2+ | 780G pump system: 7+ | 18+ |
| How it goes on [4],[2],[12],[7] | You apply it | You apply it to the back of the arm | You apply it in two steps | A provider places it under the skin |
Questions to ask your supplier
- Are you enrolled in Medicare, and do you accept assignment?
- Which CGM brands can you send me, and how fast?
- Will you ship every month or every three months?
- What do I owe each month after Medicare pays?
- Does my plan cover sensors at a pharmacy, or only through a supplier like you?
- Who do I call if a sensor fails or falls off early?
- When can I get a new reader if mine breaks?
Common questions
Does Medicare cover a CGM if I don't take insulin?
It can. You may qualify if your records show serious low blood sugar, even without insulin.[3]
How often do I need to see my doctor to keep my CGM covered?
Every six months, in person or by an approved video visit.[3]
What do I pay for a CGM with Original Medicare?
You pay 20% of the Medicare-approved amount after the Part B deductible, if the supplier accepts assignment.[1]
Can I use only my phone instead of a reader?
You can use your phone. But Medicare pays for supplies only if you also use a reader or pump some of the time.[5]
Do I have to take my CGM off at airport security?
No. Tell the officer where it is before screening starts. Devices attached to your body stay on.[6]
Reviewed & sourced
- Reviewer
- PlanScout Internal Review Team. Checks facts and plain-English accuracy; has no say in how results are ordered.
- What was checked
- Owner sign-off for the PlanScout Internal Review Team: Medicare coverage rules, costs and brand facts against the cited sources
- Last reviewed
- Oct 25, 2026
- Next review
- Before Jan 1, 2027 (new plan year), or sooner if Medicare changes a rule.
- Corrections
- See something wrong? Tell us. We fix confirmed errors within 2 business days and note the change in the page's change log.
- Change log
- Oct 25, 2026: First published and reviewed.
Sources (12)
- Medicare.gov: Continuous glucose monitors (retrieved Oct 25, 2026)
- Abbott: FreeStyle Libre important safety information (retrieved Oct 25, 2026)
- Medicare Coverage Database: Glucose Monitors, LCD L33822 (revision effective 10/01/2024) (retrieved Oct 25, 2026)
- Dexcom: Dexcom G7 overview (retrieved Oct 25, 2026)
- Medicare Coverage Database: Glucose Monitor Policy Article A52464 (revision effective 02/18/2025) (retrieved Oct 25, 2026)
- Transportation Security Administration: Disabilities and medical conditions (retrieved Oct 25, 2026)
- Senseonics: Eversense 365 receives FDA clearance (September 17, 2024) (retrieved Oct 25, 2026)
- MiniMed: Get to know the Simplera Sync sensor (retrieved Oct 25, 2026)
- Dexcom: How is Dexcom G7 15 Day different from Dexcom G7? (retrieved Oct 25, 2026)
- Abbott: FreeStyle Libre 3 system (retrieved Oct 25, 2026)
- Abbott: FreeStyle Libre 2 system (retrieved Oct 25, 2026)
- Medtronic: Simplera Sync sensor for the MiniMed 780G system now FDA approved (April 18, 2025) (retrieved Oct 25, 2026)