RETIRED - Coding and Coverage - Therapeutic Continuous Glucose Monitors (CGM)


Content Provided on this page contains outdated information and instruction and should not be considered current. Noridian is providing this archived information for research purposes only. This archived article contains previously issued instructions that have since been updated or are no longer applicable for Medicare billing purposes.

Article retired due to content incorporation into the applicable Local Coverage Determination or related Policy Article.

Joint DME MAC Article

Posted on March 23, 2017

On December 20, 2016 the Food & Drug Administration (FDA) granted premarket approval to Dexcom, Inc. for an expanded indication for their Dexcom G5® Mobile Continuous Glucose Monitoring (CGM) System.  The Dexcom G5® Mobile CGM System is now indicated to replace fingerstick blood glucose monitor (BGM) testing for diabetes treatment decisions, referred to by the FDA as "non-adjunctive" use. The Dexcom G5® Mobile CGM System is currently the only FDA-approved device with a "non-adjunctive" indication.

On January 12, 2017 the Centers for Medicare & Medicaid Services (CMS) issued CMS Ruling 1682R addressing the benefit category for non-adjunctive CGM systems.  CMS Ruling 1682R classified CGM systems into therapeutic and non-therapeutic systems.  Therapeutic CGM are defined as CGM used as a replacement for fingerstick blood glucose testing for diabetes treatment decisions i.e., non-adjunctive use.  Non-therapeutic CGM are devices used as an adjunct to BGM testing (i.e., primary therapeutic decisions regarding diabetes treatment must be made with a standard home BGM, not the CGM).

The Ruling does not directly establish Social Security Act §1862(a)(1)(A) "reasonable and necessary" (medical necessity) or HCPCS coding requirements for therapeutic CGM but instructs the DME MAC contractors to make payment determinations on a claim-by-claim basis.  This article provides interim instructions for individual claim adjudication, effective for claims with dates of service on or after January 12, 2017.

Benefit Category

CMS Ruling 1862R recognizes that therapeutic CGMs are durable medical equipment (DME) under section 1861(n) of the Act; therefore, they fall within the scope of Medicare Part B benefits. As of the publication date of this article, the Dexcom G5® Mobile CGM System is the only device which meets the therapeutic CGM device classification established by CMS Ruling 1862R.  Refer to the Pricing, Data Analysis, and Coding (PDAC) contractor for information concerning which other devices may qualify under this ruling.

Interim Instructions for Individual Claim Adjudication

HCPCS Coding

For purposes of Medicare billing, the Ruling outlines therapeutic CGM as comprising two elements: (1) a DME component and, (2) an all-inclusive supply allowance.   The DME component for the Dexcom G5® Mobile CGM system is the receiver.  The receiver must be billed using the following code:


When billing this code, suppliers must enter "Dexcom G5® Receiver" in the narrative field of the claim.

The supply allowance for supplies used with the Dexcom G5® Mobile CGM System encompasses all items necessary for the use of the device and includes, but is not limited to:  CGM sensor, CGM transmitter, home blood glucose monitor and related BGM supplies (test strips, lancets, lancing device, and calibration solutions) and all batteries. The supply allowance must be billed using the following code:


Claims for A9999 must be billed as one (1) unit of service per month.  When billing this code, suppliers must enter "Supplies used with Dexcom G5® Receiver" in the narrative field on the claim.

Smart Device Usage

The Medicare DME Benefit excludes coverage for non-medical items, even when the items may be used to serve a medical purpose.  As a result, smart devices (smart phones, tablets, personal computers, etc.) are non-covered by Medicare under this exclusion.  Likewise, medical supplies used with non-covered equipment are not eligible for Medicare reimbursement.

In addition to the DME receiver included in the Dexcom G5® Mobile CGM System, an alternative option for displaying the received data is with a smart device using the Dexcom G5® app and a beneficiary-owned smart device such as a smart phone or tablet.   Medicare does not cover a beneficiary-owned smart device.  Claims for beneficiary-owned smart devices submitted to Medicare must be coded:



Durable medical equipment, prosthetics, orthotics and supplies (DMEPOS) suppliers who provide the Dexcom G5® Mobile CGM System are reminded of the following Medicare coverage policies:

  • Coverage of the CGM system supply allowance is limited to those therapeutic CGM systems where the beneficiary ONLY uses a receiver classified as DME to display glucose data.  If a beneficiary uses a non-DME device (smart phone, tablet, etc.) as the display device, either separately or in combination with a receiver classified as DME, the supply allowance is non-covered by Medicare. 
  • Therapeutic CGM devices replace a standard home blood glucose monitor (HCPCS codes E0607, E2100, E2101) and related supplies (HCPCS codes A4233-A4236, A4244-A4247, A4250, A4253, A4255-A4259).  Claims for standard home glucose monitors and all related supplies, billed in addition to a CGM system and associated supply allowance, will be denied as unbundling.

All non-therapeutic CGM systems must be billed with the existing CGM-related HCPCS codes.  At this time, all CGM systems except the Dexcom G5® Mobile CGM System are classified by CMS as non-therapeutic CGM systems. All non-therapeutic CGM systems must be billed using the following codes: 


These codes are non-covered by Medicare (no benefit).

Beneficiary-owned Equipment Retained From a Prior Payer

There is no "grandfathering" of equipment or supplies/accessories for CGM systems obtained prior to Medicare eligibility.  When a beneficiary receiving a DMEPOS item from another payer (including a Medicare Advantage plan) becomes eligible for the Medicare Fee-For-Service program, the first Medicare claim for that item or service is considered a new initial Medicare claim. Even if there is no change in the beneficiary's medical condition, the beneficiary must meet all coverage, coding and documentation requirements for the DMEPOS item in effect on the date of service of the initial Medicare claim. 

Medicare requires that supplies and accessories only be provided for equipment that meets the existing coverage criteria for the base item. In addition, should the supply or accessory have additional, separate criteria, these must also be met.  For beneficiaries that have a Dexcom G5® Mobile CGM System who meet the coverage requirements outlined in this article, Medicare will provide reimbursement for the monthly supply allowance. 

In the event of a Medicare contractor claim review, suppliers must provide information justifying the medical necessity for the base item and the supplies and/or accessories. Refer to the coverage guidance in this article for additional information.

Patient Selection Criteria

A framework for basic medical indications is set out in the "Conclusion" section of CMS Ruling 1682R which states (in relevant part):


For CGM products that are used in the home and approved by the FDA for use in place of a blood glucose monitor for making diabetes treatment decisions, these therapeutic CGMs are primarily and customarily used to serve a medical purpose because they are used by Medicare beneficiaries with diabetes who must measure their glucose level frequently and check trends in their glucose measurements for the purpose of adjusting their diet and insulin in the treatment of their diabetes.  ...  A receiver (or type of monitor) for a therapeutic CGM that has an expected life of at least 3 years and is the component performing the medically necessary function of accurately monitoring the trends of the patients' blood glucose levels so that he or she can make necessary diabetes treatment decisions meets the 3-year MLR [minimum lifetime requirements].  [Emphasis added]

These statements provide a framework for determining which Medicare beneficiaries may receive a CGM device.  A therapeutic CGM may be covered by Medicare when all of the following criteria are met:

  • The beneficiary has diabetes mellitus; and,
  • The beneficiary has been using a home blood glucose monitor (BGM) and performing frequent (four or more times a day) BGM testing; and,
  • The beneficiary is insulin-treated with multiple daily injections (MDI) of insulin or a continuous subcutaneous insulin infusion (CSII) pump; and,
  • The beneficiary's insulin treatment regimen requires frequent adjustment by the beneficiary on the basis of therapeutic CGM testing results.

Glucose Monitors LCD and related PA Revision

The Glucose Monitors Local Coverage Determination (LCD) and related Policy Article (PA) will be updated in a future revision to incorporate the criteria outlined above.  Policy-Specific Documentation Requirements and Coding Guidelines addressing CGM systems will also be added to the Glucose Monitors LCD-related PA.  Because CMS did not provide coverage for CGM prior to the Ruling, the Glucose Monitors LCD and related PA represents a liberalization of coverage.  Therefore, when the revised LCD is published, per the CMS Program Integrity Manual (Internet-Only Manual 100-08), Chapter 13, §13.7.3, no formal comment and notice period or public meeting is required. 

The Program Integrity Manual section states, in relevant part:

13.7.3 - LCDs That Do Not Require a Comment and Notice Period

When a comment and notice period is unnecessary, contractors may immediately publish a revised LCD electronically (e.g., Medicare coverage database, contractor Web site, email).  In the following situations, the comment and notice processes are unnecessary:

  • Revised LCD that Liberalizes an Existing LCD - For example, a revised LCD expands the list of covered indications/diagnoses. The revision effective date may be retroactive.
  • Revised LCD that Makes a Non-discretionary Coverage/Payment/Coding Updates - Contractors shall update LCDs to reflect changes in NCDs, coverage provisions in interpretive manuals, payment systems, HCPCS, ICD-9 or other standard coding systems within the timeframes listed in §13.4C. The revision effective date may be retroactive depending on the effective date of the NCD, etc.

The Glucose Monitors LCD and related PA revisions will be retroactive to the effective date of the CMS Ruling (January 12, 2017). 

For questions about correct coding, contact the Pricing, Data Analysis and Coding (PDAC) contractor Contact Center at (877) 735-1326 during the hours of 8:30 a.m. to 4:00 p.m. CT, Monday through Friday, or e-mail questions to the PDAC by completing the DME PDAC Contact Form.


Last Updated Dec 11 , 2023