146Denial Code (CARC)Active
CO 146 Denial Code - Diagnosis Invalid for Service Date
Code 146 indicates that the diagnosis code submitted on the claim was not valid for the date of service. This means that the diagnosis code might have been retired, not yet effective, or simply incorrect for the given date.
Who Pays: Group Code Liability
For code 146, the group code is typically CO, meaning the provider must write off the amount and it cannot be billed to the patient. Verify with the payer if this applies.
Why Claims Get Code 146
- The diagnosis code used was retired before the date of service.
- The diagnosis code was not yet effective for the date of service.
- The diagnosis code was entered incorrectly or does not exist.
- The provider's billing system has outdated diagnosis code sets.
- The claim was submitted with an incorrect date of service.
How to Fix & Resubmit
- Verify the diagnosis code against the effective dates for the date of service.
- Check the billing system for the most current diagnosis code updates.
- Correct the diagnosis code if it was entered incorrectly.
- Submit a corrected claim with the appropriate diagnosis code.
- Contact the payer if the code seems correct but the denial persists.
Corrected Claim or Appeal?
A corrected claim is appropriate when the diagnosis code was incorrect or outdated. If the diagnosis code was valid but still denied, check with the payer before considering an appeal.
Preventing Future 146 Denials
- Regularly update billing software with the latest diagnosis code sets.
- Train staff on checking diagnosis code validity before claim submission.
- Implement a verification step for diagnosis codes against service dates.
- Schedule regular audits of diagnosis codes used in claims.