Getting a continuous glucose monitor (CGM) depends on your situation: if you use insulin or have diabetes, you’ll typically need a prescription and can go through insurance. If you don’t use insulin, you can now buy an over-the-counter option for about $89 to $99 a month with no prescription at all. Here’s how each path works.
The Over-the-Counter Option
If you have Type 2 diabetes and don’t take insulin, or if you have prediabetes and just want to see how your body responds to food, the fastest route is Dexcom’s Stelo biosensor. It became the first over-the-counter glucose biosensor in the U.S. in 2024 and requires no prescription, no doctor’s visit, and no insurance. You order it directly from Stelo.com.
A single pack of two sensors costs $99 and covers up to 30 days of wear. A monthly subscription drops the price to about $89. The device is designed for adults 18 and older who aren’t on insulin, so it won’t replace a prescription CGM for people managing Type 1 diabetes or insulin-dependent Type 2. But for anyone curious about glucose patterns or trying to improve their diet, it’s the simplest entry point.
Getting a Prescription CGM
For people on insulin or with more complex diabetes management needs, prescription CGMs like the Dexcom G7 and Abbott’s FreeStyle Libre 3 remain the standard. Getting one starts with your doctor, whether that’s a primary care physician, endocrinologist, or diabetes specialist. They write a prescription based on your diagnosis, treatment plan, and the specific device that fits your needs.
Once you have a prescription, it can be filled through two channels: a retail pharmacy (CVS, Walgreens, etc.) or a durable medical equipment (DME) supplier. The channel matters more than you’d expect.
Pharmacy vs. DME Supplier
Pharmacy fulfillment is generally faster. Your doctor fills out a simplified, one-page form documenting the medical need, and you can often pick up your sensors within days, just like any other prescription. DME suppliers, on the other hand, require a prior authorization process. That means your doctor’s office creates and submits detailed documentation showing medical necessity, including blood glucose records, history of complications, and other clinical information. In a 2024 survey of over 1,000 physicians, 89% described this paperwork burden as high or extremely high, and 93% said prior authorizations can delay access to necessary care.
Interestingly, the DME route can be cheaper in the long run. A study published in Clinical Diabetes found that Medicare patients who received CGMs through DME suppliers had significantly lower total healthcare costs at every time point measured. At 12 months, total costs averaged about $11,150 through DME compared to $15,030 through pharmacy. The trade-off is speed and convenience versus cost. If you’re on commercial insurance rather than Medicare, the difference is harder to predict because plan designs vary so widely.
What Insurance Typically Covers
Most major insurance plans, including Medicare, Medicaid, and commercial insurers, cover prescription CGMs for qualifying patients. The specifics vary by plan, but Medicare’s criteria give a good picture of what insurers generally look for. To qualify under Medicare, you need to meet all of the following:
- A diabetes diagnosis
- A prescription from your treating physician showing that you or your caregiver has been trained to use the device
- At least one of these clinical criteria: you’re treated with insulin, or you have a documented history of problematic low blood sugar. Problematic hypoglycemia means either more than one episode where glucose dropped below 54 mg/dL despite attempts to adjust your treatment, or a single severe episode where you needed someone else’s help to recover.
If your insurance denies coverage initially, your doctor can often submit an appeal with additional documentation. Many people who are denied on the first pass get approved after a more detailed letter of medical necessity.
Paying Without Insurance
If you don’t have insurance or your plan doesn’t cover a CGM, out-of-pocket costs for prescription devices can be steep. Dexcom offers a pharmacy savings program that takes $210 off the retail cash price for a 30-day sensor supply, with larger discounts for 60-day ($400 off) and 90-day ($600 off) orders. Even with these coupons, expect to pay several hundred dollars per month for a prescription CGM at full retail. Abbott’s FreeStyle Libre system tends to be somewhat less expensive at cash price, though costs fluctuate by pharmacy.
For most people paying out of pocket who don’t need a prescription-grade device, the Stelo at $89 to $99 per month is the more practical choice.
Trying a CGM Through Your Doctor’s Office
If you’re not sure whether a CGM is right for you, or your doctor wants glucose data before committing to a specific treatment plan, there’s a middle option: professional CGM. In this setup, your doctor places a clinic-owned sensor on you during an office visit. You wear it for roughly 3 to 14 days, then return it. The clinic downloads the data and reviews it with you.
Professional CGM is particularly useful if you’re newly diagnosed with diabetes, have never used a CGM before, or want to see what the experience is like before committing. It’s also a diagnostic tool for people who might be having dangerous low blood sugar episodes but don’t yet have access to a personal device. The American Association of Clinical Endocrinology recommends it for people with Type 2 diabetes on non-insulin therapies who could benefit from short-term glucose data as an educational tool. Your doctor bills the visit and sensor use to your insurance, so there’s typically no separate device cost to you beyond your normal copay.
Current Devices and Wear Time
The two most widely used prescription CGMs in the U.S. are the Dexcom G7 and the FreeStyle Libre 3. The Dexcom G7 currently lasts 10 days per sensor, though the FDA recently cleared a 15-day version expected to become available in the second half of 2025. The FreeStyle Libre 3 lasts 14 days per sensor. Both are small, disposable patches applied to the back of the upper arm or abdomen, and both send real-time glucose readings to a smartphone app.
Neither device requires finger-stick calibrations, which was a significant hassle with older models. You apply the sensor, wait through a brief warm-up period, and start getting readings. When the sensor expires, you peel it off and apply a new one. The learning curve is minimal, and most people are comfortable with the process after their first or second sensor change.