Dexcom G7 vs FreeStyle Libre 3: How to Choose

The short answer

Dexcom G7 and FreeStyle Libre 3 are both small, factory-calibrated continuous glucose monitors that send readings to your phone every few minutes. G7 has a strong ecosystem for alert sharing and pump integration; Libre 3 offers a longer 14-day wear and a very simple setup. For most people, the deciding factors are what your insurance covers, whether you use an insulin pump, and who needs to see your numbers.

Side by side

	Dexcom G7	FreeStyle Libre 3
Sensor wear	10 days plus a 12-hour grace period	14 days
Warm-up	About 30 minutes	About 60 minutes
Readings	Every 5 minutes	Every minute
Wear site	Back of upper arm (adults)	Back of upper arm
Alerts	Customizable high, low, urgent low, and rate-of-change	High, low, and signal loss
Followers	Up to 10 via Dexcom Follow	Via LibreLinkUp
Pump integration	Works with several automated insulin delivery systems	Integrations vary by system and region

Who tends to prefer G7

• People on insulin pumps who want automated insulin delivery to read glucose directly.
• Anyone who needs granular alerts — including a rising-fast or falling-fast warning, which matters for hypoglycemia unawareness.
• Families and caregivers who want multiple people following the same numbers in real time.

Who tends to prefer Libre 3

• People who want the longest stretch between sensor changes — 14 days versus 10.
• Type 2 patients not on a pump who mainly want trends and a simple low alert.
• People whose plan lists Libre as the preferred CGM brand (this varies by plan, so check before deciding).

Things people notice that spec sheets miss

Compression lows. Both sensors can read falsely low if you sleep on them. Rotating the arm you wear it on helps.

The first day. Readings are often least accurate in the first 12 to 24 hours after insertion for either device. If a number surprises you, confirm with a fingerstick before you treat.

Phone compatibility. Check your exact phone model and OS version against the manufacturer list before switching. This trips people up more than anything else.

Adhesive. Neither sensor comes with extra adhesive patches or skin prep wipes as a standard supply. If sweat, humidity, or exercise is knocking your sensor loose, ask us and we will add them to your order.

How insurance coverage works for Dexcom G7 and Libre 3

Coverage is often what decides between these two. Your plan, your diagnosis, and your prescription all matter, and every case has to be verified before supplies ship. Nothing here guarantees coverage or a price.

Medicare

Medicare covers CGMs under Part B as durable medical equipment when coverage criteria are met. Under the current Medicare policy, a person generally needs all of the following:

• A diagnosis of diabetes.
• Insulin use, or a documented history of problematic low blood sugar.
• An in-person or Medicare-approved telehealth visit with the prescriber in the six months before the order.

Medicare also expects the CGM's durable receiver (the Dexcom G7 receiver or the FreeStyle Libre 3 reader) to be used. A smartphone app can supplement it, but Medicare does not cover supplies for a CGM used with a phone alone. Once your deductible is met, you typically pay a share of the Medicare-approved amount, as Medicare explains. Secondary insurance may cover some or all of that share.

Medicaid and commercial plans

Medicaid and private insurance rules vary by state and plan. Some cover CGMs through the medical equipment benefit, others through the pharmacy benefit, and some prefer one brand. Many require prior authorization. Neither brand is automatically "the covered one."

What your prescriber usually needs to send

• A prescription for the specific CGM system.
• Chart notes showing your diabetes diagnosis and insulin use or low-blood-sugar history.
• The date of your most recent visit.

Check your coverage before you choose

Tell us which CGM you're considering and your insurance type. We'll verify your benefits for Dexcom G7, FreeStyle Libre 3, or both, and explain what your plan requires. Submitting a request does not guarantee coverage. Eligibility must be confirmed with your plan and your prescriber.

Check My Coverage or call 1-877-622-3023.

This article is for general education and is not medical or insurance advice. Talk with your clinician about which CGM is right for you.

Switching later is normal

Trying one and moving to the other is common and not a failure. Wear-site irritation, adhesive trouble, alert fatigue, or a new pump are all reasonable reasons to change. Talk to your clinician, and we will handle the paperwork side.

Your next step today

Write down the three things that matter most to you — cost, alerts, wear time, sharing, pump compatibility — and bring that list to your next appointment. Then request a coverage check on both.