CO-97 Denial Code: Service Bundled into Another Procedure
CO-97 means the billed service is bundled into another procedure already adjudicated. Learn about NCCI edits and when modifier 59 applies to CO-97 denials.
What CO-97 Means and How to Resolve It
The benefit for this service is included in the payment/allowance for another service/procedure that has already been adjudicated. Two procedures were billed together but the payer bundles one into the other per NCCI or payer-specific bundling rules. The secondary code's payment is included in the primary code's allowed amount.
- Review NCCI edits for the bundled code pair.
- If the services were truly distinct, append modifier 59 (or XS/XU/XP/XE) to the secondary code and resubmit with documentation supporting separate service performance.
- Run all claims through an NCCI edit check before submission.
- Understand payer-specific unbundling policies.
Source: X12.org Official CARC Registry
CO-97 in Detail
What does CO-97 cover in detail?
CO-97 denials occur when a service is bundled with another procedure under NCCI edits. These are often resolved by appending modifier 59 to identify it as a distinct service with supporting documentation.
Verify NCCI edit applicability and manage appeals through your denial management workflow. See all denial codes for related CARC codes.
How to Handle CO-97 Denials
How to Handle CO-97 Denials?
Identify the Root Cause
Review the claim submission to find the specific reason. Check the modifier-procedure combination and payer-specific coding requirements.
Gather Documentation
Collect the clinical documentation, EOB, and any payer communication needed to support a corrected claim or appeal.
Correct and Resubmit
Make the appropriate corrections: update codes, modifiers, or attach documentation, then resubmit within the payer's timely filing window.
Track and Prevent
Log this denial type in your denial tracking system and implement a front-end check to prevent the same issue on future claims.
Appealing a CO-97 Denial
How do I appeal a CO-97 Denial?
Corrected Claim or Appeal
These are different routes and choosing wrong costs time. If the denial was caused by something fixable on your side, a wrong modifier, a missing authorization number, or a transposed code, submit a corrected claim. It is faster and does not consume an appeal level. File a formal appeal when the original claim was correct and you believe the payer applied its policy incorrectly.
What to Submit
Include the remittance advice showing the denial, the claim as originally submitted, the clinical documentation that supports medical necessity, and a short cover letter that cites the payer's own coverage policy. Take the filing deadline from the remittance advice or determination letter for that specific claim rather than a general rule, since it differs by payer and by appeal level.
Medicare Appeal Levels
Original Medicare fee-for-service appeals move through five levels, and each one must be exhausted before the next:
- 1Redetermination by the Medicare Administrative Contractor (MAC)
- 2Reconsideration by a Qualified Independent Contractor (QIC)
- 3Decision by the Office of Medicare Hearings and Appeals (OMHA)
- 4Review by the Medicare Appeals Council
- 5Judicial review in federal district court
Source: CMS, Medicare Fee-for-Service Appeals
CO-97, PR-97, PI-97: Why the Group Code Matters
The number 97 always carries the same reason for the adjustment. The two-letter group code in front of it decides who is left owing the balance, which is why the same denial reason can arrive as CO-97 on one remittance and PR-97 on another.
Contractual Obligation. The provider absorbs the amount under the payer contract and cannot bill the patient for it.
Patient Responsibility. The balance moves to the patient and may be billed, subject to the payer agreement.
Payer Initiated Reduction. The payer reduced payment on its own initiative, not under a contractual term.
Other Adjustment. Used when neither contractual obligation nor patient responsibility applies.
Group code definitions follow the X12 claim adjustment structure.
CO-97 Denial Code Reference
| Field | Details |
|---|---|
| CARC Code | CO-97 |
| Code Group | Contractual Obligation (CO) |
| Official Description | The benefit for this service is included in the payment/allowance for another service/procedure that has already been adjudicated. |
| Common Cause | Two procedures were billed together but the payer bundles one into the other per NCCI or payer-specific bundling rules. The secondary code's payment is included in the primary code's allowed amount. |
| Resolution | Review NCCI edits for the bundled code pair. If the services were truly distinct, append modifier 59 (or XS/XU/XP/XE) to the secondary code and resubmit with documentation supporting separate service performance. |
| Prevention | Run all claims through an NCCI edit check before submission. Understand payer-specific unbundling policies. Only use modifier 59 when services genuinely meet the separate-service criteria. |
Source: X12.org Official CARC Registry
Related Billing Resources
CO-97, Frequently Asked Questions
The benefit for this service is included in the payment/allowance for another service/procedure that has already been adjudicated.
Two procedures were billed together but the payer bundles one into the other per NCCI or payer-specific bundling rules. The secondary code's payment is included in the primary code's allowed amount.
Review NCCI edits for the bundled code pair. If the services were truly distinct, append modifier 59 (or XS/XU/XP/XE) to the secondary code and resubmit with documentation supporting separate service performance.
Run all claims through an NCCI edit check before submission. Understand payer-specific unbundling policies. Only use modifier 59 when services genuinely meet the separate-service criteria.
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