835 Denial Combination

CO-97

CO

Contractual Obligation · Service-Line Level Adjustment

Coding Error

What This Combination Means

This adjustment indicates the provider billed a service separately that is already bundled into payment for another procedure on the same claim or a previously adjudicated claim. The payer has reduced payment to zero or a lower amount because reimbursement was already included in a primary or comprehensive procedure code. This is a contractual bundling edit, not a coding error that can be challenged if the bundling rule is correct.

Financial Responsibility

provider writeoff

The provider must write off the adjusted amount as it represents duplicate payment for a service already reimbursed within another procedure's allowance, per contract terms.

N/A

Appeal Success

Immediate (write-off)

Avg. Resolution

Easy

Difficulty

No

Appealable

Step-by-Step Resolution

Steps tailored specifically to this CO-97 combination — not generic advice.

Not Appealable:This is a contractual bundling adjustment based on the payer's fee schedule and payment policies that the provider agreed to in their contract.
  1. 1

    Identify the primary procedure code that includes this service

    Review the ERA's Healthcare Policy Identification Segment (loop 2110 Service Payment Information REF) to determine which procedure code already includes payment for this bundled service.

  2. 2

    Verify bundling rules in the payer's fee schedule or editing software

    Confirm whether the bundling edit is correct according to CCI edits, payer-specific bundling rules, or the contract terms to determine if this is expected behavior.

  3. 3

    Write off the contractual adjustment and update billing practices

    Apply the contractual write-off adjustment and modify charge entry or coding protocols to prevent billing bundled components separately in future claims.

Specialty Context

How CO-97 typically presents across different practice types.

Dental

Common when billing separate codes for procedures included in comprehensive treatments, such as billing prophylaxis components separately when included in a periodontal maintenance procedure code.

Medical

Frequently occurs with surgical add-on codes, E/M services on procedure dates, or ancillary services bundled into primary procedures per NCCI edits or payer-specific bundling rules.

Behavioral Health

May occur when billing individual therapy sessions separately on the same date as group therapy or psychotherapy with E/M services that are bundled per payer policy.

Individual Code References

View the standalone definition for each code in this combination.

Medicare Contractor Guidance for CARC 97

FCSO + Noridian

There are a few scenarios that exist for denial reason code CO 97. Please review the associated remittance advice remark code (RARC) noted on the remittance advice for your claim and then refer to the specific resources and tips to prevent the denial.

How to Prevent CARC 97 Denials

  • RARC M15 (Bundled services): If the procedure code has a 'b' status on the Medicare Physician Fee Schedule (MPFS) database, the service should not be billed to Medicare. Check your most frequently billed procedure codes on the First Coast fee schedule lookup tool — if status is 'b', do not bill Medicare.

  • RARC M144 (Pre/post-operative care): If billing for split care, coordinate split-care billing activities with other provider(s) involved in the patient's care, and ensure the surgical code is billed before the services for post-operative care are billed.

  • RARC N70 (Consolidated billing): Before providing services to a Medicare beneficiary, determine if a home health episode exists. Ask the beneficiary if they are receiving home health services under a home health plan of care. Always check beneficiary eligibility prior to submitting your claim via SPOT.

CMS IOM, Pub. Medicare Claims Processing Manual 100-04, Chapter 12, section 20.3CMS IOM, Pub. 100-04 Claims Processing Manual, Chapter 12, section 40CMS IOM, Pub. 100-04 Claims Processing Manual, Chapter 10First Coast fee schedule lookup toolSPOTHHA documentation reportsNoridian Medicare PortalNMPIVRSame or Similar

Need to resolve this denial?

Get a complete resolution plan with appeal guidance for this exact combination in seconds.

Generate a free resolution plan & appeal letter →

Synthesized from official definitions — not from training data

Was this helpful?