CO-199: Revenue Code and Procedure Code Mismatch
Correct the revenue code to match the procedure code and resubmit. Do not appeal this coding error.
What Does CO-199 Mean?
With CO (Contractual Obligation), the revenue/procedure code mismatch is the provider's billing error. Correct the code combination and resubmit. Do not appeal — this is a correctable coding issue.
CARC 199 is a coding error specific to institutional (UB-04) claims where the revenue code and the CPT/HCPCS procedure code do not form a valid combination. Revenue codes categorize the type of service or department, while procedure codes identify the specific service performed. Payers validate these combinations and reject claims when the codes conflict.
This denial commonly results from data entry errors, outdated chargemaster entries, confusion between facility and professional billing requirements, or unbundling errors. The fix is straightforward — identify the correct revenue code for the procedure and resubmit.
Common Causes
| Cause | Frequency |
|---|---|
| Incorrect revenue code for the procedure The revenue code selected does not correspond to the CPT/HCPCS procedure code billed, creating an invalid combination that the payer's system rejects | Most Common |
| Coding errors or typographical mistakes Manual entry errors during claim submission resulted in a revenue code that does not match the procedure performed | Most Common |
| Unbundling errors Services that should be billed under a single revenue code were improperly separated into multiple codes that conflict with the procedure code | Common |
| Outdated coding guidelines Provider used revenue codes based on prior-year guidelines that have since been updated or retired | Common |
| Facility vs professional billing confusion Revenue codes appropriate for institutional billing were used incorrectly with professional procedure codes or vice versa | Common |
| Missing or incorrect modifiers The claim lacks required modifiers that would properly align the revenue code with the procedure code | Occasional |
How to Resolve
- Identify the mismatch Determine which revenue code and procedure code are conflicting.
- Look up the correct combination Reference the UB-04 manual and payer billing guidelines for the correct pairing.
- Correct and resubmit Update the claim with the correct codes and resubmit.
- Update chargemaster if needed If this is a recurring issue, update the chargemaster to prevent future mismatches.
This is a billing/coding error where the revenue code does not match the procedure code. Correct the code combination and resubmit the claim rather than filing an appeal.
Common RARC Pairings
The RARC code tells you exactly what triggered the CO-199:
| RARC | Description |
|---|---|
| M15 | Separately billed services/tests have been bundled as they are considered components of the same procedure. Review whether the revenue and procedure codes should be billed as a bundled service → |
| MA130 | Your claim contains incomplete and/or invalid information, and no appeal rights are afforded. Correct the revenue/procedure code combination and resubmit as a new claim rather than appealing → |
| N522 | Adjustment based on a review of the coding. Review and correct the coding combination per current guidelines and resubmit → |
How to Prevent CO-199
- Conduct regular audits of revenue code and procedure code matching in your chargemaster
- Implement claim scrubbing software with built-in revenue/procedure code validation checks
- Provide comprehensive coding staff training on current revenue code requirements
- Maintain up-to-date chargemaster entries that reflect current CPT and revenue code pairings
- Establish clear coding policies and procedures for institutional claim submission
- Track denial trends for CARC 199 to identify recurring mismatch patterns
Also Filed As
The same CARC 199 may appear with different Group Codes:
Related Denial Codes
Sources
- https://x12.org/codes/claim-adjustment-reason-codes
- https://www.mdclarity.com/denial-code/199
- https://portal.ct.gov/-/media/ohs/health-it-advisory-council/apcd-advisory-group/data-submission-guide-workgroup/meeting-materials/6-30-22/carc-codes_final.pdf
- https://www.aapc.com/resources/claim-adjustment-reason-codes
- Codes maintained by X12. Visit x12.org for official definitions.