How do I resolve a CO-200 denial?

Verify the exact dates of service against the patient's coverage termination or lapse dates in the payer's eligibility system: Confirms whether services truly fell during an inactive coverage period Check if the patient had coverage through a different payer or plan during the lapse period: Patient may have switched plans or carriers during the gap, making another payer primary Post the contractual adjustment as a write-off and update the account to reflect zero patient balance: CO group code prohibits transferring this balance to patient responsibility

835 Denial Combination

CO-200

Contractual Obligation · Claim-Level Adjustment

Eligibility

What This Combination Means

This code indicates services were rendered during a period when the patient's insurance coverage had lapsed or was inactive. The payer has applied a contractual adjustment requiring the provider to write off the denied amount rather than collecting from the patient, despite the eligibility issue being the patient's responsibility to maintain.

Financial Responsibility

provider writeoff

The provider must absorb this cost as a contractual write-off. Even though coverage lapsed due to patient non-payment or non-enrollment, the CO group code prohibits patient billing for this adjustment.

N/A

Appeal Success

Immediate (write-off)

Avg. Resolution

Easy

Difficulty

Appealable

Step-by-Step Resolution

Steps tailored specifically to this CO-200 combination — not generic advice.

Not Appealable:Coverage lapse is a factual eligibility determination that cannot be appealed; the contractual obligation requires write-off regardless.

1
Verify the exact dates of service against the patient's coverage termination or lapse dates in the payer's eligibility system
Confirms whether services truly fell during an inactive coverage period
2
Check if the patient had coverage through a different payer or plan during the lapse period
Patient may have switched plans or carriers during the gap, making another payer primary
3
Post the contractual adjustment as a write-off and update the account to reflect zero patient balance
CO group code prohibits transferring this balance to patient responsibility

Specialty Context

How CO-200 typically presents across different practice types.

Dental

Common when patients fail to maintain voluntary dental plan premiums or when employer-sponsored coverage terminates mid-month but services were provided after the last day of active coverage

Medical

Frequently occurs with marketplace/ACA plans when patients miss premium payments, COBRA lapses due to non-payment, or when retroactive terminations occur due to non-payment discovered after claims are filed

Behavioral Health

May appear for ongoing therapy or medication management services when patients lose coverage mid-treatment due to premium non-payment or loss of qualifying status for Medicaid

Individual Code References

View the standalone definition for each code in this combination.

CARC 200

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Synthesized from official definitions — not from training data

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