Very CommonContractual Obligation (CO)Coding & Billing
CO-16: Claim/service lacks information needed for adjudication
The claim or service lacks information that is needed for adjudication. Additional information is required from the provider before the payer can process this claim. This is one of the most common denial codes and is often a catch-all for missing data elements.
Common Causes
- Missing or invalid patient demographic information (DOB, gender, subscriber ID)
- Missing referring or ordering provider NPI
- Missing place of service code or invalid POS
- Missing or invalid taxonomy code
- Required attachments (operative notes, medical records) not submitted
- Missing accident date or onset date when required
How to Resolve CO-16
- 1Check the remittance advice for accompanying RARC codes that specify what information is missing
- 2Review the claim for completeness against payer requirements
- 3Obtain the missing information and resubmit the claim
- 4If all required information was submitted, appeal with proof of original submission
- 5Contact the payer to clarify exactly what additional information they need
How to Prevent CO-16 Denials
- Implement pre-submission claim validation that checks for all required fields
- Use claim scrubbing software to catch missing data before submission
- Maintain up-to-date provider enrollment data (NPI, taxonomy, credentials)
- Train front desk staff to collect complete demographic and insurance information
Related Denial Codes
Stop Denials Before They Happen
Greenlight validates procedure and diagnosis code combinations against payer rules before claims are submitted, catching coding errors before they become denials.
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