Overview
The CGM market in 2026
The CGM device market has split into two distinct segments: prescription medical devices for diabetes management, and over-the-counter wellness devices for people without diabetes who want metabolic insights. Understanding which segment you belong to is the first step in choosing the right device.
Prescription CGMs — Dexcom G7, Abbott FreeStyle Libre 3, Medtronic Guardian 4 — are approved for diabetes management and meet the clinical accuracy standards required for insulin dosing decisions. They require a prescription in most countries and are covered by insurance for eligible patients.
OTC CGMs — Dexcom Stelo and Abbott Lingo — are FDA-cleared for adults without diabetes and available without a prescription at pharmacies and online. They use similar sensor technology but are designed as wellness tools rather than medical devices, with software optimized for behavioral insights rather than clinical management.
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Which category are you?
If you have diabetes (Type 1 or Type 2) or prediabetes, talk to your healthcare provider before choosing a CGM. Prescription devices are covered by insurance for many patients, making them significantly more affordable than OTC options. If you do not have diabetes and are interested in metabolic health monitoring, OTC devices are designed for you and are available without a medical appointment.
Prescription CGM
Prescription devices for diabetes
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Dexcom G7
Dexcom · Prescription required
The Dexcom G7 is the current flagship prescription CGM and the benchmark against which other devices are measured. Significantly smaller than its predecessor (the G6), it integrates the sensor and transmitter into a single disposable unit — simplifying the system and reducing the profile on the body. It delivers readings every five minutes with a MARD of 8.2%, supports direct-to-Apple-Watch display without a phone intermediary, and is compatible with major automated insulin delivery (AID) systems.
10 days
Wear time
8.2%
MARD accuracy
2hr
Warm-up time
~$35/mo
With insurance
Strengths
- Smallest all-in-one design on the market
- Direct Apple Watch display (no phone needed)
- Widest AID system compatibility
- 30-minute grace period after 10-day sensor expiry
- Strong insurance coverage in US
- Excellent app with pattern insights
Limitations
- 10-day wear is shorter than Libre 3's 15 days
- Higher out-of-pocket cost without insurance
- Abdomen and upper arm placement only
- Requires prescription
Best for
People with Type 1 diabetes using or considering closed-loop insulin delivery. Also excellent for Type 2 patients on insulin who want the most comprehensive data and Apple Watch integration. The reference standard for clinical CGM in 2026.
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Abbott FreeStyle Libre 3
Abbott · Prescription required
The FreeStyle Libre 3 is Abbott's current flagship prescription CGM, combining the world's smallest CGM sensor with 15-day wear and real-time Bluetooth streaming. It delivers readings every minute — more frequently than Dexcom's five-minute interval — and achieves a best-in-class MARD of 7.8%. The Libre 3 Plus extends wear to 15 days with improved connectivity. Abbott's LibreLink app includes a comprehensive data analysis platform and the LibreLinkUp companion app for real-time sharing with caregivers.
15 days
Wear time
7.8%
MARD accuracy
60min
Warm-up time
~$30/mo
With insurance
Strengths
- Longest wear time of major CGMs (15 days)
- Highest published MARD accuracy (7.8%)
- World's smallest sensor form factor
- 1-minute reading interval (vs 5 min for Dexcom)
- Shorter warm-up time (60 min vs 2hr)
- Often lower cost with insurance than Dexcom
Limitations
- Limited closed-loop AID compatibility vs Dexcom
- No direct Apple Watch display
- Upper arm placement only
- Requires prescription
Best for
People with Type 2 diabetes and those prioritizing accuracy and sensor longevity. The 15-day wear and best-in-class MARD make it the leading choice for patients not using closed-loop AID systems. Often the more economical prescription option.
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Medtronic Guardian 4
Medtronic · Prescription required
The Guardian 4 is Medtronic's current CGM sensor, designed primarily for use with Medtronic's MiniMed insulin pump systems in a closed-loop configuration. It offers factory calibration and 7-day wear. The Guardian 4 is best understood as a component of the Medtronic closed-loop ecosystem rather than a standalone CGM — its strengths lie in integration with Medtronic pumps rather than standalone use.
7 days
Wear time
8.8%
MARD accuracy
2hr
Warm-up time
Varies
With insurance
Strengths
- Deep integration with Medtronic pump ecosystem
- Proven closed-loop algorithm (780G system)
- Factory calibrated — no finger-sticks required
Limitations
- Shortest wear time of major CGMs (7 days)
- Higher MARD than Dexcom and Libre
- Best suited for Medtronic pump users only
- Limited standalone app functionality
Best for
Existing Medtronic MiniMed pump users who want closed-loop functionality within the Medtronic ecosystem. Not recommended as a first-choice standalone CGM given shorter wear time and lower accuracy versus competitors.
Over-the-counter CGM
OTC devices — no prescription needed
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Dexcom Stelo
Dexcom · No prescription required
Dexcom Stelo was the first FDA-cleared OTC CGM device, launched in 2024. It uses the same core sensor technology as the G7 but is FDA-cleared for adults 18+ who do not use insulin, including people with Type 2 diabetes managed without insulin, prediabetes, and those without any diagnosis seeking metabolic insights. The Stelo app focuses on behavioral insights — showing how specific foods, activities, and sleep affect glucose — rather than clinical management features. Available at major pharmacies and online without a prescription.
15 days
Wear time
~8.5%
MARD accuracy
No Rx
Availability
~$99/mo
Retail price
Strengths
- No prescription required — available at CVS, Walgreens, Amazon
- 15-day wear — longer than prescription G7
- Dexcom sensor reliability and quality
- App designed for behavioral insights and habit change
- Food logging with glucose response correlation
- Apple Health and Google Health integration
Limitations
- Not for insulin users — Rx G7 required
- No low glucose alerts (not cleared for alarm use)
- Not covered by insurance as wellness device
- Higher cost than Rx with insurance coverage
Best for
The leading OTC CGM choice for people without diabetes interested in metabolic health, as well as non-insulin-using Type 2 patients who cannot get insurance coverage for prescription CGM. Dexcom's brand reliability and 15-day sensor are significant advantages over the prescription G7's 10-day wear.
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Abbott Lingo
Abbott · No prescription required
Abbott Lingo is Abbott's OTC CGM, built on the FreeStyle Libre sensor platform and cleared for adults without diabetes. The Lingo system emphasizes coaching and habit formation — the app provides personalized glucose coaching, tracks "Lingo Points" (a proprietary glucose stability score), and offers meal and activity recommendations. Like the Libre 3, it achieves high sensor accuracy and offers 14-day wear. Available without prescription at major retailers.
14 days
Wear time
~8.0%
MARD accuracy
No Rx
Availability
~$89/mo
Retail price
Strengths
- Slightly lower cost than Stelo
- Built-in glucose coaching and recommendations
- Abbott's industry-leading sensor accuracy
- 14-day wear — competitive with Stelo
- Lingo Points score makes data accessible to non-technical users
Limitations
- Coaching model may feel prescriptive for some users
- Less raw data access than Stelo for advanced users
- Upper arm placement only
- Not covered by insurance
Best for
People new to CGM who want guided coaching rather than raw data. The Lingo Points system and built-in recommendations make it more accessible for people who find CGM data overwhelming. Slightly more affordable than Stelo with comparable sensor performance.
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Eversense E3
Senseonics · Prescription required
The Eversense E3 is the only implantable CGM approved for long-term use, lasting 6 months before replacement. A small sensor is implanted subcutaneously by a healthcare provider in an office procedure, providing six months of continuous monitoring without sensor changes. The external smart transmitter is worn over the implant site and can be removed for swimming or charging. On-body vibration alerts (the transmitter vibrates on the skin) provide alerts without a phone in range.
180 days
Wear time
~9.1%
MARD accuracy
Office Rx
Requires implant
Varies
Insurance dependent
Strengths
- 6-month wear — eliminates frequent sensor changes
- On-body vibration alerts without phone
- Removable transmitter for swimming, charging
- No adhesive patch irritation
- Ideal for people with adhesive allergies
Limitations
- Requires minor surgical procedure for insertion and removal
- Lower accuracy than Dexcom and Libre
- Limited availability of trained inserting providers
- Not compatible with AID systems
- Higher cost per year than disposable sensors
Best for
People who find frequent sensor changes burdensome, have adhesive allergies or skin sensitivities, or have an active lifestyle where a removable transmitter is advantageous. A niche but genuinely useful option for the right patient profile.
Side by side
Full comparison table
| Device | Prescription | Wear time | MARD | AID compatible | Est. monthly cost |
|---|---|---|---|---|---|
| Dexcom G7 | Required | 10 days | 8.2% | Yes (multiple) | ~$35 (insured) |
| FreeStyle Libre 3 | Required | 15 days | 7.8% | Limited | ~$30 (insured) |
| Medtronic Guardian 4 | Required | 7 days | 8.8% | Medtronic only | Varies |
| Dexcom Stelo | Not required | 15 days | ~8.5% | No | ~$99 (OTC) |
| Abbott Lingo | Not required | 14 days | ~8.0% | No | ~$89 (OTC) |
| Eversense E3 | Required + implant | 180 days | ~9.1% | No | Varies |
Decision guide
How to choose the right CGM
If you have Type 1 diabetes and use insulin
Dexcom G7
Broadest closed-loop compatibility, best app ecosystem, and the reference standard for intensive insulin management. Work with your endocrinologist to confirm insurance coverage and AID system compatibility.
If you have Type 2 diabetes on insulin
FreeStyle Libre 3
Best accuracy, longest wear, and often the most affordable prescription option with insurance. Excellent for patients who want reliable glucose data without closed-loop complexity.
If you have Type 2 not on insulin or prediabetes
Ask your doctor first
Coverage has expanded significantly. Many patients in this category now qualify for prescription CGM coverage. If covered, a prescription device gives better clinical features than OTC options. If not covered, Stelo or Lingo are practical alternatives.
If you don't have diabetes but want metabolic insights
Dexcom Stelo or Abbott Lingo
Both are designed for you. Choose Stelo if you want raw data and more flexibility. Choose Lingo if you want guided coaching and a simpler experience. Both are available without a prescription at major pharmacies.
If you have adhesive allergies or dislike sensor changes
Eversense E3
The 6-month implantable sensor eliminates both the adhesive patch and frequent sensor changes. Requires a minor office procedure but offers the most convenient long-term monitoring experience once implanted.
If you use a Medtronic insulin pump
Medtronic Guardian 4
Deep integration with the MiniMed 780G closed-loop system makes Guardian 4 the natural choice for Medtronic pump users. The closed-loop algorithm compensates for the lower standalone CGM accuracy within the integrated system.
Always consult your healthcare provider
CGM device selection for diabetes management should be made with your endocrinologist or diabetes care provider. Insurance coverage, AID system compatibility, and your specific clinical situation all affect which device is right for you. This guide provides general information — not personalized medical advice.
FAQ
Frequently asked questions
Can I use a prescription CGM without diabetes?
Technically yes — prescription CGMs can be obtained with a prescription for off-label use. However, OTC devices (Stelo, Lingo) are specifically designed and priced for wellness use, offer comparable sensor technology, and do not require a medical appointment. For most people without diabetes, OTC CGM is the more practical and economical path. Note that OTC devices are not cleared for insulin dosing decisions and should not be used as substitutes for prescription devices in people with diabetes who require insulin.
Does insurance cover CGM?
Coverage has expanded significantly. Medicare covers CGM for all patients with diabetes who use insulin. Most private insurance plans cover prescription CGM for patients with Type 1 diabetes and for Type 2 patients on insulin; coverage for non-insulin Type 2 patients is improving but variable. OTC devices (Stelo, Lingo) are not covered by insurance as they are classified as wellness devices. Prior authorization requirements vary by insurer — your provider's office can help navigate coverage requirements and submit necessary documentation.
Is Dexcom G7 better than FreeStyle Libre 3?
Neither is definitively better — they are optimized for different use cases. The Libre 3 has a slight accuracy edge (7.8% vs 8.2% MARD) and longer wear (15 vs 10 days). The G7 has broader closed-loop AID compatibility and direct Apple Watch display. For most Type 2 patients not using closed-loop therapy, the Libre 3's better accuracy and longer wear are meaningful advantages. For Type 1 patients considering or using AID systems, the G7's compatibility is more important. Both are excellent devices.
How long does it take to get used to wearing a CGM?
Most people adapt quickly — within one to two sensor changes (2–4 weeks). The initial adjustment involves learning to apply sensors correctly, managing the adhesive patch during activities and bathing, and learning to interpret the data the device provides. Physically, sensor wear is rarely noticeable after the first day. The larger adjustment is cognitive — learning to respond calmly to glucose fluctuations rather than reacting to every individual reading. Most users report that CGM becomes second nature within a month.
Are OTC CGMs as accurate as prescription devices?
For wellness monitoring purposes, yes — OTC CGMs use the same core sensor technology as prescription devices and achieve similar MARD values. The difference is not in sensor accuracy but in the clinical features: OTC devices lack low glucose alarms approved for hypoglycemia alerting, are not cleared for insulin dosing decisions, and are not compatible with closed-loop AID systems. For tracking metabolic health, food responses, and general glucose patterns, OTC CGM accuracy is more than sufficient.