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181
CO - Contractual ObligationCoding/Billing
Denial Code CO-181: Procedure Code Invalid on Date of Service
What Does Code 181 Mean?
Procedure code was invalid on the date of service. The CPT/HCPCS code used has been deleted or was not yet effective.
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?
Using an outdated or not-yet-active procedure code.
How to Resolve It
- 1Verify the correct CPT/HCPCS code for the date of service
- 2Use the current year's code set
- 3Resubmit with the correct procedure code
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