CO-110: Billing Date Predates Service Date

What Does CO-110 Mean?

With CO (Contractual Obligation), the CARC 110 adjustment is the provider's responsibility. The payer denied or reduced payment because of the claim was electronically submitted or received by the payer before the date of service listed on the claim, which is a billing integrity violation. The patient is not liable for this amount.

CARC 110 is used when the payer determines that billing date predates service date. The claim could not be processed as submitted because required information was absent, incomplete, or did not meet the payer's submission standards.

Common scenarios that trigger this adjustment include: the claim was electronically submitted or received by the payer before the date of service listed on the claim, which is a billing integrity violation; A data entry error placed the wrong date of service on the claim, making it appear as though the service has not yet occurred at the time of billing; The date fields in the electronic claim were formatted incorrectly, causing the payer's system to interpret the dates as the billing date predating the service date. The group code paired with CARC 110 determines who bears the financial responsibility — CO places it on the provider as a contractual obligation, PR shifts it to the patient, OA indicates a coordination of benefits or other payer adjustment.

Common Causes

How to Resolve

1. Review the remittance details Examine the CO-110 adjustment and any accompanying RARC codes to identify the specific reason for the denial.
2. Identify the root cause Determine which issue applies: claim submitted before service date, incorrect date of service on claim, date format error in electronic submission, among others.
3. Correct the claim Address the identified issue — update the claim data in your billing system to resolve the billing date predates service date problem.
4. Resubmit the corrected claim Submit the corrected claim following the payer's resubmission guidelines. Include any supporting documentation that addresses the denial reason.

Common RARC Pairings

The RARC code tells you exactly what triggered the CO-110:

How to Prevent CO-110

• Implement claim validation rules that prevent submission of claims with future dates of service
• Review batch claim submissions to ensure all dates of service are in the past
• Verify date of service accuracy during charge capture before claims are submitted
• Train billing staff on the importance of accurate date of service entry
• Test electronic claim date format compatibility with each payer's requirements

Also Filed As

The same CARC 110 may appear with different Group Codes:

Related Denial Codes