835 Denial Combination

CO-120

CO

Contractual Obligation · Claim-Level Adjustment

What This Combination Means

The patient must use providers from within the managed care network. The billed provider is not in the patient's assigned network or plan.

30%

Appeal Success

21-45 days

Avg. Resolution

Hard

Difficulty

Yes

Appealable

Step-by-Step Resolution

Steps tailored specifically to this CO-120 combination — not generic advice.

  1. 1

    Confirm the provider's network status in the patient's specific plan.

  2. 2

    If the provider is in-network, submit proof of participation and appeal.

  3. 3

    If the provider is out-of-network, verify whether the patient had emergency circumstances (No Surprises Act may apply).

  4. 4

    If elective OON: inform the patient of their OON financial responsibility.

Specialty Context

How CO-120 typically presents across different practice types.

Dental

Verify the patient must use providers from within the managed care network per your dental plan contract and documentation requirements.

Medical

Confirm the patient must use providers from within the managed care network against payer policy and submit corrected claim as needed.

Behavioral Health

Apply behavioral health parity rules and confirm the patient must use providers from within the managed care network per MHPAEA standards.

Individual Code References

View the standalone definition for each code in this combination.

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