CO-97 Denial — How to Appeal for Behavioral Health
CO-97 (bundled / already adjudicated) is one of the most common insurance denial codes behavioral health therapists encounter. This guide explains what triggered the denial and the most effective appeal strategy across all major payers.
What CO-97 means
The payer says this service is included in another service that's already been billed and paid. In behavioral health, this most commonly happens when an E/M visit (99213/99214) and psychotherapy (90834/90837) are billed on the same day without the -25 modifier on the E/M code to establish that it is a separately identifiable service.
Appeal strategy for CO-97
Cite documentation establishing the services as separately identifiable — distinct CPT codes, a separate clinical purpose for each, and (when applicable) the -25 modifier on the E/M code. Reference CMS NCCI Edit Policy Chapter 11, which explicitly permits same-day E/M + psychotherapy when -25 is applied. If the modifier was present and the denial is still issued, request the specific NCCI edit being invoked.
CPT codes commonly denied with CO-97
Appeal CO-97 by payer
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Generate my appeal letter →Frequently asked questions about CO-97
What does CO-97 mean on a behavioral health claim?
The payer says this service is included in another service that's already been billed and paid. In behavioral health, this most commonly happens when an E/M visit (99213/99214) and psychotherapy (90834/90837) are billed on the same day without the -25 modifier on the E/M code to establish that it is a separately identifiable service.
How do I appeal a CO-97 denial?
Cite documentation establishing the services as separately identifiable — distinct CPT codes, a separate clinical purpose for each, and (when applicable) the -25 modifier on the E/M code. Reference CMS NCCI Edit Policy Chapter 11, which explicitly permits same-day E/M + psychotherapy when -25 is applied. If the modifier was present and the denial is still issued, request the specific NCCI edit being invoked.
Does MHPAEA apply to CO-97 denials?
CO-97 is a general adjudication code that typically applies equally to all claim types. MHPAEA may still be relevant if the payer applies the underlying rule differently to mental health services than to comparable medical/surgical services.
Which insurers most commonly issue a CO-97 denial?
All major commercial payers — Aetna, Cigna, Anthem, UnitedHealthcare, Humana, and BCBS plans — use CO-97. Government programs (Medicare, Medicaid, TRICARE) also issue this code. The appeal strategy is similar across payers, but deadlines and submission addresses vary. Select your payer from the list below for payer-specific instructions.