Choosing between Dexcom G7 and FreeStyle Libre 3 Plus is one of the most common decisions seniors face when starting continuous glucose monitoring. If you’re wondering about the differences in Dexcom G7 vs FreeStyle Libre 3 Plus, both are excellent CGM systems covered by Medicare, but they have important differences that matter for older adults. This comprehensive comparison will help you make the right choice for your needs.
About This Guide: This comparison is based on official specifications from Dexcom and Abbott Diabetes Care, combined with real-world feedback from seniors using these devices. Our recommendations follow Medicare coverage guidelines and are reviewed for accuracy by certified diabetes educators.
Quick Comparison: Dexcom G7 vs FreeStyle Libre 3
| Feature | Dexcom G7 | FreeStyle Libre 3 Plus |
|---|---|---|
| Sensor Wear Time | 10 days | 15 days |
| Warm-Up Time | 30 minutes | 60 minutes |
| Size | Size of a nickel | Size of a penny |
| Accuracy (MARD) | 8.1% | 7.9% |
| Water Resistance | 24 hours at 8 feet | 30 minutes at 3 feet |
| Calibration | Optional (can calibrate) | No calibration option |
| Bluetooth Range | ~20 feet | ~33 feet |
| Medicare Cost | Covered (copay varies) | Covered (copay varies) |
| Retail Cost | ~$89/month (Simple Start) | ~$40/month (most insured) |
Accuracy: Both Are Highly Reliable
Quick Answer: Both CGM systems deliver excellent accuracy with MARD ratings under 9%. FreeStyle Libre 3 Plus has a slightly lower MARD of 7.9% compared to Dexcom G7’s 8.1%, but both are highly reliable for daily diabetes management. Dexcom G7 offers optional calibration if readings seem off.
Both CGM systems deliver excellent accuracy for daily diabetes management. The FreeStyle Libre 3 Plus has a slightly lower MARD (Mean Absolute Relative Difference) of 7.9% compared to Dexcom G7’s 8.1%, but in practical terms, both are highly accurate and trusted by healthcare providers.
Key difference: The Dexcom G7 allows optional calibration with fingerstick readings if you notice the sensor seems off. The Libre 3 has no calibration option—if readings seem inaccurate, your only option is to replace the sensor.
Key Statistics: CGM adoption among Medicare beneficiaries has increased over 300% since 2020. Studies show CGM technology reduces A1C by 0.5-1.0% on average, and CGM users check their glucose levels approximately 16 times per day compared to just 4 times with traditional fingerstick testing. With 1 in 4 adults over 65 living with diabetes, choosing the right CGM system has never been more important.
Sensor Wear Time: Libre 3 Plus Wins
Quick Answer: FreeStyle Libre 3 Plus sensors last 15 days compared to Dexcom G7’s 10 days. This means fewer sensor changes per month (2 vs 3), less time spent on insertions, and potentially lower supply costs—a significant advantage for seniors who find sensor changes challenging.
The FreeStyle Libre 3 Plus sensor lasts 15 days compared to Dexcom G7’s 10 days. This means:
- Fewer sensor changes per month (2 vs 3)
- Less time spent on insertions
- Potentially lower costs for supplies
For seniors who find sensor changes challenging or who have caregivers helping with insertions, the longer wear time can be a significant advantage.
Alerts and Alarms: Dexcom G7 Offers More Options
Quick Answer: Dexcom G7 provides more sophisticated alarm features including Urgent Low Soon alerts, rise/fall rate notifications, and more customizable thresholds. For seniors at risk of hypoglycemia or those needing advance warning of glucose changes, Dexcom’s alert system offers extra peace of mind.
Both systems provide customizable high and low glucose alerts, but Dexcom G7 offers more sophisticated alarm features:
- Urgent Low Soon alert: Warns you before you go low
- Rise/Fall rate alerts: Notifies when glucose is changing rapidly
- Customizable thresholds: More flexibility in setting alert levels
For seniors at risk of hypoglycemia or those who need advance warning of glucose changes, Dexcom’s alert system may provide extra peace of mind.
App and Display: Both Work Well for Seniors
Quick Answer: Both systems display glucose readings on smartphone apps with large, easy-to-read numbers. FreeStyle Libre 3 offers an optional standalone reader for $70-80, making it the better choice for seniors who prefer not to use a smartphone.
Both systems display glucose readings on smartphone apps with large, easy-to-read numbers. Key considerations:
- Dexcom G7: Works with Dexcom app or compatible smart watches
- FreeStyle Libre 3 Plus: Uses LibreLink app; optional standalone reader available for $70-80
If you prefer not to use a smartphone, the Libre system’s standalone reader may be a better fit. The reader has a simple interface and doesn’t require any technical setup.
Medicare Coverage: Both Are Covered
Quick Answer: Medicare Part B covers both Dexcom G7 and FreeStyle Libre 3 Plus for qualifying seniors with diabetes who use insulin and test frequently. Most seniors pay $0-50 per month after insurance, depending on their supplemental coverage.
Good news: Medicare Part B covers both Dexcom G7 and FreeStyle Libre 3 Plus for qualifying beneficiaries. To qualify, you typically need:
- Diabetes diagnosis requiring insulin
- Multiple daily insulin injections or insulin pump use
- Frequent glucose self-testing (4+ times daily)
- Doctor’s prescription and documentation
Your out-of-pocket costs will depend on whether you have supplemental insurance (Medigap) or Medicare Advantage. Many seniors pay $0-50 per month after insurance.
Related Reading: If you’re new to CGM technology, check out our CGM Sensor Insertion Tips for Seniors for step-by-step guidance. Also see our guide to the Stelo OTC CGM—the first over-the-counter option that doesn’t require a prescription.
Which CGM Is Right for You?
Choose Dexcom G7 if you:
- Want the option to calibrate sensors
- Need advanced predictive alerts for hypoglycemia
- Use an insulin pump (better integration options)
- Prefer a faster warm-up time
Choose FreeStyle Libre 3 Plus if you:
- Want longer sensor wear time (fewer changes)
- Prefer a smaller, more discreet sensor
- Want a standalone reader option (no smartphone required)
- Are looking for lower out-of-pocket costs
Related Resources for Seniors
Explore more CGM guides designed specifically for older adults:
- CGM Sensor Insertion Tips for Seniors – Step-by-step insertion guidance with tips for arthritis and dexterity challenges
- Stelo OTC CGM Guide – Learn about the first over-the-counter glucose monitor available without a prescription
Frequently Asked Questions About CGMs for Seniors
Which CGM is better for seniors, Dexcom G7 or FreeStyle Libre 3?
Quick Answer: Both are excellent choices. Dexcom G7 offers better customizable alerts and family sharing features, making it ideal for seniors who want caregiver monitoring. FreeStyle Libre 3 has a simpler setup process and slightly lower cost with Medicare, making it better for seniors who prefer simplicity.
Does Medicare cover both Dexcom G7 and FreeStyle Libre 3?
Quick Answer: Yes, Medicare Part B covers both CGM systems for qualifying seniors with diabetes. Coverage is typically 80% after deductible, with most seniors paying $50-75 monthly out of pocket. You need a prescription and must be using insulin or checking blood sugar 3+ times daily to qualify.
Which CGM has better accuracy for seniors?
Quick Answer: Both have similar accuracy ratings (MARD around 8.5-9%). Dexcom G7 has a 30-minute warm-up time compared to 60 minutes for FreeStyle Libre 3, meaning faster accurate readings after sensor insertion. Both are FDA-approved for making treatment decisions without fingerstick confirmation.
Can family members see my CGM readings remotely?
Quick Answer: Yes, both systems offer remote monitoring. Dexcom G7’s “Share” feature allows up to 10 followers to see real-time readings and receive alerts. FreeStyle Libre 3’s “LibreLinkUp” app provides similar functionality, letting caregivers monitor glucose levels from anywhere.
Which CGM is easier to apply for seniors with arthritis?
Quick Answer: FreeStyle Libre 3 has a slightly simpler one-piece applicator that many seniors with limited dexterity find easier. Dexcom G7 requires a two-step process but has larger grip areas. Both manufacturers offer applicator aids, and many seniors find either manageable after 2-3 applications.
The Bottom Line
Both Dexcom G7 and FreeStyle Libre 3 Plus are excellent CGM choices for seniors. They’re both accurate, Medicare-covered, and can significantly improve diabetes management. The “best” choice depends on your individual priorities—whether that’s longer wear time, advanced alerts, cost, or ease of use.
Talk to your doctor or diabetes educator about which system might work best for your specific situation. Many people try one system and later switch to the other, so don’t worry too much about making the “perfect” choice—both will help you better manage your glucose levels.
Need help getting started with CGM? Contact us at 727-831-3729 for personalized guidance on Medicare coverage and choosing the right system for you.
