Glucose Monitoring — Continuous Glucose Monitoring (CGM) Coverage
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Policy governing coverage and prior authorization rules for implantable and non-implantable continuous glucose monitors for Blue Cross Blue Shield - Rhode Island members, with distinctions for Medicare Advantage and commercial products.
No material clinical or coverage changes in this revision.
Coverage Criteria for Continuous Glucose Monitoring
Implantable CGM — Medicare Advantage (Initial coverage)
Covered when ALL of the following are met:
Non-Implantable CGM — Medicare Advantage
Covered when device is designated as therapeutic or adjunctive:
For therapeutic devices, file claims with HCPCS K0554 and K0553; adjunctive devices have E2102 and A4238 as applicable.
Coverage by device classification and benefit
Coverage depends on device classification (therapeutic vs adjunctive), benefit type, and coding:
Claims for adjunctive CGMs with dates of service on/after Feb 28, 2022 may be covered under Part B when the system meets the DME definition.
BCBSRI requires PDAC listing for devices to be considered covered under K0554.
Suppliers must use E2102/A4238 (effective 4/1/2022) for adjunctive CGM claims thereafter.
Implantable CGM coverage — Implantable CGM procedural coverage
Implantable CGM procedural coverage:
G0308 and G0309 are new codes effective 7/01/2022.
Coverage statements and distinctions
Coverage and medical necessity statements and distinctions:
See CPT code descriptions for required components.
A9276–A9278 are not covered for Medicare Advantage per CMS guidance.
G0308 and G0309 are new codes effective 7/01/2022.
Per this policy, the use of implantable continuous glucose monitoring (CGM) devices is considered not medically necessary for Commercial Products because the evidence is insufficient to determine effects on health outcomes.
The policy lists specific non-covered items and coding guidance. Items not covered include certain antiseptics (A4244–A4247), urine test reagent strips (A4250), reflectance colorimeter devices, glucose monitors not designed for home use (A9270), and home disposable monitors/test strips (A9275). For adjunctive (non-implantable) CGM receivers and supplies, BCBSRI requires billing under HCPCS E2102 and A4238 and considers filing claims with A9276–A9278 to be incorrect; suppliers should follow the specified HCPCS coding guidance.
The policy identifies HCPCS codes A9276, A9277, and A9278 as codes that are not covered for Medicare Advantage Plans per CMS guidance but remain covered for Commercial Products. BCBSRI also notes that A9276 and A9277 are not to be used to bill supplies associated with E2102 and K0554.
This policy reiterates that, for Commercial Products, implantable CGM devices are not medically necessary due to insufficient evidence to demonstrate meaningful improvement in health outcomes.
BCBSRI specifies that HCPCS codes A9276–A9278 are not covered for Medicare Advantage per CMS (while these codes may be used for Commercial Products); suppliers should instead bill adjunctive CGM receivers and monthly supplies under E2102 and A4238 as required by the policy.
Certain procedure codes for implantable CGM insertion and removal have differing medical necessity across product lines. Code 0446T (creation of subcutaneous pocket with insertion of implantable interstitial glucose sensor) is considered medically necessary for Medicare Advantage when criteria are met but is listed as not medically necessary for Commercial Products. Codes for removal and replacement (0447T, 0448T, and G0309) have coverage tied to the Removal of Implantable Devices policy and may be medically necessary for Medicare Advantage and, in some cases, for Commercial Products when those removal criteria are satisfied.
Coding and Reimbursement
| K0553 | Supply allowance for therapeutic continuous glucose monitor (CGM), includes all supplies and accessories, 1 month supply = 1 unit of service |
| K0554 | Receiver (monitor), dedicated, for use with therapeutic continuous glucose monitor system |
| A9276 | Sensor; invasive (e.g. subcutaneous) disposable, for use with interstitial continuous glucose monitoring system, 1 unit = 1 day supply |
| A9277 | Transmitter; external, for use with interstitial continuous glucose monitoring system |
| A9278 | Receiver (monitor); external, for use with interstitial continuous glucose monitoring system |
| 0446T | Creation of subcutaneous pocket with insertion of implantable interstitial glucose sensor, including system activation and patient training |
| G0308 | Creation of subcutaneous pocket with insertion of 180 day implantable interstitial glucose sensor, including system activation and patient training (New code effective 7/01/2022) |
| 0447T | Removal of implantable interstitial glucose sensor from subcutaneous pocket via incision |
| 0448T | Removal of implantable interstitial glucose sensor with creation of subcutaneous pocket at different anatomic site and insertion of new implantable sensor, including system activation |
| G0309 | Removal of implantable interstitial glucose sensor with creation of subcutaneous pocket at different anatomic site and insertion of new 180-day implantable sensor, including system activation (New code effective 7/01/2022) |
| 0446T | Creation of subcutaneous pocket with insertion of implantable interstitial glucose sensor, including system activation and patient training |
| G0308 | Creation of subcutaneous pocket with insertion of 180 day implantable interstitial glucose sensor, including system activation and patient training (New code effective 7/01/2022) |
| 0447T | Removal of implantable interstitial glucose sensor from subcutaneous pocket via incision |
| 0448T | Removal of implantable interstitial glucose sensor with creation of subcutaneous pocket at different anatomic site and insertion of new implantable sensor, including system activation |
| G0309 | Removal of implantable interstitial glucose sensor with creation of subcutaneous pocket at different anatomic site and insertion of new 180-day implantable sensor, including system activation (New code effective 7/01/2022) |
| 95249 | Ambulatory continuous glucose monitoring of interstitial tissue fluid via a subcutaneous sensor for a minimum of 72 hours; patient-provided equipment, sensor placement, hook-up, calibration of monitor, patient training, and printout of recording |
| 95250 | Ambulatory continuous glucose monitoring of interstitial tissue fluid via a subcutaneous sensor for a minimum of 72 hours; sensor placement, hook-up, calibration of monitor, patient training, removal of sensor, and printout of recording |
| 95251 | Ambulatory continuous glucose monitoring of interstitial tissue fluid via a subcutaneous sensor for a minimum of 72 hours; interpretation and report |
| A4238 | Transmitter; CGM supply (monthly) (per policy language) |
| E2102 | Adjunctive continuous glucose monitor or receiver (New Code Effective 4/1/2022) |
| E1399 | Durable medical equipment, miscellaneous (temporary use Feb 28, 2022–Mar 31, 2022) |
| A9999 | Miscellaneous DME supply or accessory, not otherwise specified (temporary use Feb 28, 2022–Mar 31, 2022) |
| A9276 | Sensor; invasive (e.g. subcutaneous) disposable, for use with interstitial continuous glucose monitoring system, 1 unit = 1 day supply |
| A9277 | Transmitter; external, for use with interstitial continuous glucose monitoring system |
| A9278 | Receiver (monitor); external, for use with interstitial continuous glucose monitoring system |
| S1030 | Continuous non-invasive glucose monitoring device, purchase |
| S1031 | Continuous non-invasive glucose monitoring device, rental, including sensor, sensor replacement, and download to monitor |
Provider Action Items, Authorization & Billing Guidance
Prior authorization required for implantable CGM (Medicare Advantage)
Prior authorization is required for use of implantable continuous glucose monitoring (I-CGM) for Medicare Advantage plans and must be obtained via BCBSRI's online prior authorization tool for participating providers.
Pharmacy benefit authorization for retail-obtained CGMs
Dexcom and Abbott FreeStyle Libre devices obtained from retail pharmacies require authorization through BCBSRI's Pharmacy Benefit Management vendor (covermymeds.com); the same branded devices obtained from a Durable Medical Equipment (DME) provider do not require authorization.
Implantable CGM procedure codes — medical necessity differs by product/benefit
Implantable CGM insertion and related removal/replacement procedure codes are considered medically necessary for Medicare Advantage when the medical criteria are met; coverage for Commercial Products differs and some implantable codes are not considered medically necessary for commercial members.
- Medicare Advantage: 0446T, G0308, 0447T, 0448T, G0309 are addressed as insertion/removal/replacement codes considered medically necessary when criteria are met.
- Commercial Products: use of implantable CGM devices is stated as not medically necessary in some cases (see Commercial sections and Related Policies).
Authorization pathway depends on acquisition source (DME vs pharmacy)
Dexcom and Abbott FreeStyle Libre devices obtained through a DME provider do not require authorization; retail-obtained devices obtained via pharmacy require pharmacy benefit authorization through the PBM vendor.
Incorrect coding of adjunctive/therapeutic CGM supplies may cause denial
Billing adjunctive CGM devices and supplies under HCPCS A9276–A9278 is considered incorrect; BCBSRI requires these to be billed under E2102 and A4238, and incorrect coding may trigger claim denial.
- A9276–A9278 are noted as not to be used to bill therapeutic/adjunctive devices for Medicare Advantage and use may lead to denial.
- Up to a 90-day supply of K0553 or A4238 may be billed when billed correctly.
In-person visit required within 6 months before ordering I-CGM
Treating physician must have had an in-person visit with the member within six months prior to ordering the implantable CGM to evaluate diabetes control and confirm that the medical criteria (diabetes diagnosis, insulin treatment, frequent regimen adjustment) are met.
Maintain documentation for potential BCBSRI audit
BCBSRI may audit services and requires that all documentation be made available upon request; failure to produce requested information may result in denial or retraction of payment.
Required HCPCS codes and permitted temporary codes for adjunctive/implantable CGMs
Use the specified HCPCS codes for adjunctive CGM receivers and supplies (E2102, A4238) and for implantable CGM procedures (0446T, G0308, 0447T, 0448T, G0309); for dates of service Feb 28, 2022–Mar 31, 2022 suppliers were instructed to use miscellaneous codes E1399 or A9999 for adjunctive CGM claims where applicable.
Coverage-dependent denial risk for implantable CGM (commercial vs Medicare Advantage)
Commercial use of implantable CGM devices is considered not medically necessary (not covered) due to insufficient evidence; Medicare Advantage implantable CGM may be covered only when the listed medical criteria are met — failure to meet the applicable criteria risks claim denial.
Denial risk if CGM does not meet CMS therapeutic definition or if BGM billed with therapeutic CGM
Claims for CGMs that do not meet the CMS definition of therapeutic CGM will be denied as non-covered; billing blood glucose monitoring (BGM) supplies in addition to an approved therapeutic CGM will be denied as not covered per CMS Ruling 1682R.
Background and Rationale
This policy distinguishes implantable versus non-implantable CGMs and addresses the regulatory classification of devices as therapeutic (used to make treatment decisions without confirmatory blood glucose monitoring) versus adjunctive (intended to supplement BGM). Coverage and billing requirements differ by device type and benefit: non-implantable therapeutic CGMs are covered when they meet CMS definitions and are billed under appropriate DME HCPCS codes, while adjunctive devices must be billed under E2102/A4238 per BCBSRI guidance.
Definitions
Revision History
Policy last reviewed on 2022-04-11.
Policy effective date established as 2022-04-01.
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