Denial codes / CO-11
CO-11 denial: meaning, fix & appeal letter template
The ICD-10 code doesn't support the CPT code billed.
What it means
Official CARC 11 descriptionThe diagnosis is inconsistent with the procedure.
The payer's edits don't accept the diagnosis on the claim as a reason for the service — either the ICD-10 code isn't on the payer's (or LCD's) covered list, or the diagnosis pointer links the line to the wrong diagnosis.
Common causes
- Diagnosis pointer linked to the wrong ICD-10 code
- Unspecified or truncated ICD-10 code when the payer requires specificity
- Supporting diagnosis documented but not coded on the claim
- Diagnosis not on the covered list in the applicable LCD/payer policy
- Sex- or age-conflicting diagnosis/procedure combination
How to fix it
- Check diagnosis pointers on the denied line first — this is the most common cause
- Review the note for a more specific or additional supporting diagnosis
- Check the LCD/NCD or payer policy's covered ICD-10 list for the CPT
- If coding was wrong: submit a corrected claim
- If coding was right: appeal with the documentation and policy reference
Appeal or corrected claim?
Corrected claim if the coding was wrong; appeal if it was right. If the documentation supports a different or more specific diagnosis, fix it and resubmit. If the claim was coded correctly and the payer's edit is too narrow, appeal with the clinical note and the coverage policy showing the diagnosis supports the service.
What to attach
- Clinical note documenting the diagnosis and reason for the service
- Coverage policy / LCD excerpt listing the diagnosis as supporting
- Corrected claim (if coding was changed)
CO-11 appeal letter template
Replace every [BRACKETED] field. Remove any optional paragraph that doesn't apply.
[PRACTICE NAME] [ADDRESS] · [PHONE] · NPI [NPI] · TIN [TIN] [DATE] [PAYER NAME] Attn: Appeals / Provider Disputes [PAYER APPEALS ADDRESS] Re: Request for Reconsideration — Claim [CLAIM NUMBER] Patient: [PATIENT NAME] Member ID: [MEMBER ID] DOB: [DOB] Date of Service: [DOS] CPT: [CPT CODE] Billed: [AMOUNT] Denial: CO-11 — The diagnosis is inconsistent with the procedure. Dear Appeals Reviewer, We request reconsideration of the denial of the above claim. The above service was denied with CARC 11, indicating the diagnosis is inconsistent with the procedure. The patient's diagnosis of [ICD-10 CODE — DESCRIPTION] is documented in the enclosed [OFFICE NOTE / REPORT] dated [DATE] and directly supports CPT [CPT CODE] because [CLINICAL RATIONALE]. [PAYER NAME] policy [POLICY NAME/NUMBER] [and/or LCD L[NUMBER]] lists [ICD-10 CODE] as a covered indication for this service. Based on the enclosed documentation, we request that [PAYER NAME] overturn this denial and reprocess the claim for payment in accordance with the member's benefits and our participation agreement. Enclosures: - Clinical note documenting the diagnosis and reason for the service - Coverage policy / LCD excerpt listing the diagnosis as supporting - Corrected claim (if coding was changed) Please contact [CONTACT NAME] at [PHONE] or [EMAIL] with any questions. Sincerely, [NAME], [TITLE] [PRACTICE NAME]
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