CO 167 denial code

Claim adjustment reason code 167. Often reported as CO 167 or PR 167.

Diagnosis not covered

Unofficial reference. This is our own plain-English explanation, not the official code text. Payer rules differ. Verify with the payer and the official X12 code list. AlphaPrefix is not affiliated with X12, CMS or any payer. Data last updated Nov 11, 2026.

What 167 means

The payer will not pay because the diagnosis or diagnoses on the claim are not covered for this service.

The payer does not consider the reported diagnosis a covered reason for this service. This often happens when coverage policies list specific diagnoses that support medical need.

The remittance may include a policy reference that names the rule. Check that the claim carries the diagnosis that best describes the reason for the service and is in the record.

Group codes seen with 167

On a remittance, 167 comes after a group code. These are the ones it is most often reported with:

• CO 167 (Contractual Obligation): The provider's side of the ledger. The reduction comes from the payer contract or a rule the provider has to follow, and the patient normally cannot be billed for it.
• PR 167 (Patient Responsibility): The amount is assigned to the patient. Deductibles, coinsurance and copays are the everyday examples. Whether you can collect it still depends on your contract and the patient's plan.

The payer chooses the group code for each adjustment, so the same reason code can appear with another group code on your remittance. Read the two together. More about group codes.

Common causes

• The diagnosis is not on the payer's list of covered reasons for the service.
• A less specific or secondary diagnosis was listed when a covered one was in the record.
• The diagnosis pointer linked the service to the wrong diagnosis.

What to do next

1. Check the remittance for a policy reference and read the covered diagnoses list.
2. Review the record for a diagnosis that supports the service and is documented.
3. Correct the diagnosis or pointer and resubmit if the claim was coded wrong.
4. Check whether a signed waiver lets you bill the patient for a non-covered service.

Related codes

• 50 (reason code) Not medically necessary per the payer
• 146 (reason code) Diagnosis invalid for the date of service
• 96 (reason code) Service not covered by the plan