CO 24 denial code

Claim adjustment reason code 24. Often reported as CO 24.

Covered under capitation or managed care

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 24 means

The service is paid through a capitation or managed care arrangement, so there is no separate fee-for-service payment.

The payer is saying the service is already covered by a capitation payment, a fixed amount per member paid to the provider or a group, or by a managed care plan that handles the claim separately.

If your contract is capitated for this service, the adjustment is usually expected. If you are not capitated, or the patient is enrolled in a different plan than billed, the claim likely went to the wrong place. It is usually reported with CO.

Group codes seen with 24

On a remittance, 24 comes after a group code. These are the ones it is most often reported with:

• CO 24 (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.

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 service is included in the provider's or group's capitation agreement.
• The patient is enrolled in a managed care plan that should have received the claim instead of the payer billed.
• The patient's primary care assignment is with a capitated group or provider.

What to do next

1. Check whether your contract with the payer is capitated and whether this service is included.
2. Verify the patient's plan and any managed care enrollment for the date of service.
3. Bill the managed care plan or delegated group if the claim went to the wrong entity.
4. Ask the payer to review the claim if the service is carved out of the capitation agreement.

Related codes

• 22 (reason code) Another payer may be primary
• 45 (reason code) Charge exceeds the allowed amount
• 27 (reason code) Service after coverage ended