CO 167 denial code

What CO-167 means

CO-167 says the payer looked at the diagnosis codes on your claim and decided they are not covered for the service billed. Payers publish coverage policies that list which diagnoses justify a given procedure. For Medicare, that means national coverage determinations (NCDs) and the local coverage determinations (LCDs) written by each MAC. If none of your claim’s diagnosis codes appear on that list, the line denies with 167.

The CO group code makes the balance a contractual obligation. You absorb it; the patient cannot be billed unless liability was properly shifted in advance (for Medicare, that means a valid ABN and the corresponding modifier, which changes the denial handling entirely).

Common causes

• The claim carries a general or symptom-level diagnosis when the payer’s policy requires a more specific code.
• The correct, covered diagnosis is in the medical record but never made it onto the claim.
• The diagnosis pointer on the service line points to the wrong diagnosis in the claim’s diagnosis list.
• An LCD or NCD changed and a diagnosis that used to support the service no longer does.
• The service genuinely is not covered for the patient’s condition under the payer’s policy.

How to fix and resubmit

1. Read the remittance in full. Check the 835 healthcare policy segment (loop 2110 REF) if present; it often names the exact policy applied. For Medicare, look up the LCD or NCD for the billed code.
2. Compare the covered-diagnosis list in that policy against the medical record. Do not compare it against the claim first; the record is the source of truth.
3. If a covered diagnosis is documented but missing from the claim, or a diagnosis pointer is wrong, submit a corrected claim with the right codes and pointers. This is the fastest path and needs no appeal.
4. If the documentation supports coverage but no listed diagnosis fits cleanly, appeal (for Medicare, a redetermination within 120 days of the remittance date) with the clinical notes attached. Explain how the patient’s condition meets the policy’s criteria.
5. If the record genuinely does not support a covered diagnosis, write off the CO amount. Do not amend documentation after the fact to fit the policy.

How to prevent it

Load LCD and NCD diagnosis requirements into your claim scrubber for your high-volume procedures, and re-check them quarterly (policies change). Train providers on the specificity payers expect, especially for tests with narrow coverage lists (vitamin D assays, sleep studies, and similar frequent LCD targets). When a front-end edit flags a non-covered diagnosis before submission, route the chart back to the provider for clarification rather than picking a “close enough” code. For Medicare patients who want a service their diagnosis will not support, issue an ABN before the service so liability is settled up front.

Related denials: CO-50 (not medically necessary) and CO-11 (diagnosis inconsistent with the procedure). Full list at the denial codes index.