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178
CO - Contractual ObligationCoverage
Denial Code CO-178: Date of Service Before Effective Date
What Does Code 178 Mean?
Dates of service are prior to the patient's date of coverage with this payer.
Group Code CO (Contractual Obligation): The provider has agreed to accept the payer's determination. The patient is generally not responsible for this amount.
Why Does This Happen?
Service provided before the patient's insurance effective date.
How to Resolve It
- 1Verify coverage effective date
- 2Check for retroactive coverage
- 3Bill the appropriate payer that was active on the date of service
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