A Continuous Glucose Monitor (CGM) is a medical device that tracks glucose levels, eliminating the need for constant fingerstick tests. This technology provides a comprehensive view of glucose trends, which is a powerful tool for managing diabetes. However, the recurring expense of the sensors can be a significant financial barrier for many users. Understanding the true costs and available strategies for minimizing out-of-pocket spending is essential when searching for the most affordable option.
Direct Comparison: The Most Affordable CGM Systems
The most affordable continuous glucose monitoring system available to cash-paying consumers is the FreeStyle Libre line of products. The FreeStyle Libre 2 and Libre 3 systems from Abbott typically have the lowest retail price points for their disposable sensors. Without insurance or discounts, the average cash price for two 14-day FreeStyle Libre 2 sensors is approximately $235.
The main competitor, the Dexcom G7, is often priced substantially higher. An average cash price for a 30-day supply (three 10-day sensors) falls between $480 and $572. Since Libre sensors last 14 days compared to the Dexcom G7’s 10 days, the per-day cost of the Libre system is lower for an uninsured buyer. Prescription discount cards can significantly close this gap, sometimes reducing the cost of a single Libre 2 sensor to between $66 and $87.
Understanding the Total Cost: Factors Driving CGM Pricing
CGM systems consist of a disposable sensor and a transmitter, which is either separate or integrated into the sensor. The FreeStyle Libre systems incorporate the transmitter into the disposable sensor, simplifying the process and contributing to the lower overall cost compared to systems requiring a separate transmitter.
The distinction between coverage under the pharmacy benefit and the Durable Medical Equipment (DME) benefit is a complex factor influencing cost. Insurance plans may cover the same device differently depending on whether it is classified as a prescription drug (pharmacy benefit) or a medical supply (DME benefit).
Traditional Medicare covers CGMs under Part B as DME, which often means an annual deductible followed by a 20% coinsurance payment. Commercial insurance plans frequently cover CGMs through the pharmacy benefit, which typically involves a predictable, lower copayment. The difference in these coverage channels can result in vastly different out-of-pocket costs for the same device.
Practical Strategies for Reducing Out-of-Pocket Expenses
Commercial Insurance and Copay Assistance
Patients with commercial insurance often pay a low, flat copayment for FreeStyle Libre sensors, sometimes as little as $75 per month. This is often due to manufacturer-sponsored copay assistance programs. These savings cards effectively cap the monthly out-of-pocket expense for commercially insured individuals.
Medicare Coverage
Medicare coverage is provided under Part B as DME, requiring the user to meet specific criteria, such as being treated with insulin or having a history of problematic hypoglycemia. Once the annual Part B deductible is met, the user is responsible for 20% of the Medicare-approved amount.
Discount Cards
Individuals without insurance can utilize prescription discount cards, like those offered by GoodRx or SingleCare. These cards can reduce the cash price of a 14-day Libre sensor to under $70.
Beyond Price: Trade-offs in Choosing Affordable CGMs
Choosing an affordable CGM system involves trade-offs in technical performance and user experience. The accuracy of a CGM is measured by its Mean Absolute Relative Difference (MARD) rating; a lower percentage indicates closer agreement with laboratory blood glucose values. The FreeStyle Libre 3 system boasts a MARD of 7.9%. The older FreeStyle Libre 2 has a slightly higher MARD, ranging from 9.2% to 9.7% for adults and children.
The systems also differ in functionality, particularly whether they are real-time or require scanning. Both the FreeStyle Libre 2 and Libre 3 are factory-calibrated, meaning they do not require fingerstick calibration. The Libre 3 system is a real-time CGM that automatically sends readings every minute to a compatible smartphone. In contrast, the Libre 2 is an intermittently scanned system that requires the user to manually scan the sensor for the current reading.