CGM supply coding and billing

CGM supply coding and billing: For non-adjunctive (non-implantable) devices, bill device and supplies with HCPCS A4239 (supply allowance, non-adjunctive) and E2103 (non-adjunctive CGM or receiver). For adjunctive devices, bill with HCPCS A4238 (supply allowance, adjunctive) and E2102 (adjunctive CGM or receiver). Up to a 90-day supply of A4238/A4239 may be billed and is reimbursable by BCBSRI. Claims for devices dispensed under the Pharmacy benefit must still include the appropriate HCPCS when billed under DME.

• A4239 — Supply allowance for non-adjunctive, non-implanted CGM (1 month = 1 unit).
• E2103 — Non-adjunctive, non-implanted continuous glucose monitor or receiver.
• A4238 — Supply allowance for adjunctive, non-implanted CGM (1 month = 1 unit).
• E2102 — Adjunctive, non-implanted continuous glucose monitor or receiver.
• Up to 90-day supply of A4238/A4239 may be billed.

Device-specific billing pathway

Device-specific billing pathway: Certain non-adjunctive devices are explicitly listed and must be billed to BCBSRI using A4239 and E2103. Devices not PDAC-listed for E2103 will not be covered for Medicare Advantage. Dexcom G5, Dexcom G6, and Abbott FreeStyle Libre are classified as non-adjunctive and must follow the A4239/E2103 pathway. Commercial retail pharmacy-dispensed Dexcom and Abbott FreeStyle Libre devices are covered through the member’s Pharmacy Benefit (no PA effective 10/1/2025) or via a DME provider under the subscriber's DME benefit.

• Dexcom G5, Dexcom G6, Abbott FreeStyle Libre — file under A4239 and E2103.
• PDAC listing required for E2103 coverage for Medicare Advantage.
• Retail pharmacy pathway for Dexcom/Abbott effective 10/1/2025 (no PA for Commercial Products).

Prior authorization — implantable and ambulatory CGM

Prior authorization — implantable and ambulatory CGM: Implantable CGM surgical procedures (0446T, 0447T, 0448T) and ambulatory CGM services (95249–95251) are covered when medically appropriate. For implantable CGM insertion (0446T), the code is globally reimbursed for procedure and device; a separate same-day E&M may be billed only if it is a distinct, separately identifiable service and must include modifier 25.

• 0446T — Creation of subcutaneous pocket with insertion of implantable interstitial glucose sensor (globally reimbursed).
• 0447T — Removal of implantable interstitial glucose sensor.
• 0448T — Removal with creation of new pocket and insertion of new implantable sensor.
• 95249, 95250, 95251 — Ambulatory CGM services (monitoring, placement/removal, interpretation/report).
• Modifier 25 required to identify separately billable E&M on same day as 0446T.

Not covered HCPCS

Not covered HCPCS: The following HCPCS will be denied / are not covered under the DME benefit for home use when billed inappropriately: A9270 and A9275 are statutorily not covered for home use and will be denied; A9276–A9278 are not the correct codes to bill for non-/adjunctive CGM devices and supplies and their use for E2102/E2103-related items is considered incorrect billing and may trigger denials.

• A9270 — Glucose monitors not designed for home use — will be denied (no benefit).
• A9275 — Home blood glucose disposable monitor and strips — not covered.
• A9276, A9277, A9278 — Not to be used to bill supplies for devices covered under E2102/E2103 (incorrect billing).

Modifier requirement

Modifier requirement: Per CMS guidance, claims for blood glucose monitoring equipment and related supplies must include modifier KX if the member is insulin treated, or modifier KS if the member is non‑insulin treated. The KX modifier must not be used for members not treated with insulin injections. Missing or incorrect modifiers may result in claim denial.

• Modifier KX — use when beneficiary is insulin treated; do not use KX if not treated with insulin.
• Modifier KS — use when beneficiary is non‑insulin treated.
• Ensure required modifier present on every HCPCS supply code line to avoid denial.

Incorrect supply billing risk

Incorrect supply billing risk: Do not bill supplies associated with adjunctive or non-adjunctive CGM devices using HCPCS A9276–A9278. BCBSRI requires supplies for adjunctive devices be billed under A4238/E2102 and for non‑adjunctive devices under A4239/E2103. Using A9276–A9278 for these supplies is inappropriate and may trigger denials or audit adjustments.

• A9276–A9278 — inappropriate for supplies tied to E2102/E2103; will trigger denials.
• Use A4238 with E2102 for adjunctive devices.
• Use A4239 with E2103 for non‑adjunctive devices.

Pre-order visit documentation

Pre-order visit documentation: For both implantable and non‑implantable CGM, within six (6) months prior to ordering the CGM the treating practitioner must have performed an in-person or Medicare‑approved telehealth visit to evaluate diabetes control and document that the clinical criteria for CGM use are met (e.g., insulin treatment or qualifying hypoglycemia history). Maintain this documentation and make it available to BCBSRI upon request.

• In‑person or Medicare‑approved telehealth visit within 6 months prior to ordering CGM.
• Documentation must confirm criteria: insulin-treated OR history of problematic level 2/3 hypoglycemia, or equivalent clinical rationale.
• Failure to produce documentation may result in denial or retraction of payment.

HCPCS + NDC on claims

HCPCS + NDC on claims: To ensure correct claims processing for Medicare Advantage products, file claims with both the HCPCS code and the NDC for the device dispensed. Include required modifiers (KX or KS) on HCPCS supply lines. PDAC listing must be confirmed for devices billed to E2103.

• File HCPCS and NDC on the claim for the device dispensed.
• Include KX or KS modifier on each HCPCS supply line as applicable.
• Verify PDAC listing for devices billed under E2103 for Medicare Advantage coverage.