Service not covered as per member certificate (Updated for 2026)

Common Causes for CO-189

Denials with code CO-189 typically happen for the following specific reasons:

• The billed CPT or HCPCS code represents a standard plan exclusion, such as cosmetic procedures, routine foot care, or infertility treatments.
• The procedure is classified as experimental, investigational, or unproven under the payer's current medical coverage guidelines.
• The patient has already exhausted the maximum annual or lifetime benefit limits for the specific category of service rendered.
• The service was performed by an out-of-network provider under a plan that strictly limits coverage to in-network benefits.

How to Prevent CO-189 Denials

To avoid receiving this denial in the future, implement these specific checks:

• Perform comprehensive eligibility and benefits verification prior to rendering services to identify plan-specific exclusions.
• Obtain a signed member financial responsibility waiver or Advanced Beneficiary Notice (ABN) before performing services suspected to be non-covered.
• Cross-reference scheduled CPT/HCPCS codes with the payer's medical policies and the patient's summary of benefits during pre-registration.
• Utilize real-time eligibility (RTE) tools to check for category-specific maximum benefit limitations before scheduling repeating therapy sessions.

Appeal Letter Template for CO-189

If you believe this claim was denied incorrectly, you can use the following template to submit an appeal.

[Your Practice Header]
[Date]

[Payer Name]
[Appeals Department Address]

RE: Appeal for Claim [Claim Number]
Patient: [Patient Name]
ID: [Patient ID]
Date of Service: [Date]
Denial Code: CO-189 - Service not covered as per member certificate

Dear Appeals Department,

I am writing to appeal the denial of the above-referenced claim, which was denied with code CO-189: "Service not covered as per member certificate".

We are appealing the denial of the billed service under code CO-189, which indicates the service is excluded under the member's certificate. A clinical review of the attached medical records demonstrates that the procedure performed was not an elective or excluded service, but rather a medically necessary reconstructive intervention as defined under CMS guidelines and standard AMA coding conventions. The patient's underlying clinical pathology and functional impairment elevate this service beyond a standard plan exclusion, making it an essential, non-cosmetic component of their active treatment plan. We request a manual clinical review of the enclosed medical records to grant an exception and process this claim for payment.

Attached please find:
1. A copy of the original claim.
2. The relevant medical records supporting the service.
3. [Any other supporting documents].

We respectfully request that you reprocess this claim for payment.

Sincerely,

[Your Name]
[Title]
[Practice Name]