Instantly find explanations, causes, and resolution steps for every Claim Adjustment Reason Code (CARC) and Remark Code.
Claim Adjustment Reason Codes (CARC) explain why a payment differs from what was billed. Every 835 ERA and EOB uses these standardized codes.
Search any code or keyword above. Each page includes the full description, common causes, resolution steps, and appeal guidance.
Each denial code page also links to a dedicated Remark Code page — optimized for providers searching for ERA remark code context.
Most denials are reversible. Our guides walk you through the correct steps to correct, resubmit, or formally appeal each denial type.
| Code | Description | View |
|---|---|---|
| 124 | Payer refund amount - not our patient. Start: 01/01/1995 | Last Modified: 06/30/1999… | Details → |
| 124 | Denied. The beginning/ending service date is missing or invalid. | Details → |
| 125 | Invoice Submit claim with invoice. | Details → |
| 125 | Submission/billing error(s). At least one Remark Code must be provided (may be compri… | Details → |
| 125 | Denied. Bill was received in L&I after 90 days from date of service. | Details → |
| 126 | Total mismatch Claim total does not match detail line total. | Details → |
| 126 | Deductible -- Major Medical Start: 02/28/1997 | Last Modified: 09/30/2007 | Stop: 04… | Details → |
| 126 | Payment processed. Future vouchers for travel over 90 days old will be denied. | Details → |
| 127 | Diag required Per CMS regulations this benefit requires specific diagnosis codes. | Details → |
| 127 | Coinsurance -- Major Medical Start: 02/28/1997 | Last Modified: 09/30/2007 | Stop: 0… | Details → |
| 127 | Denied. The prescription was not written by the recognized attending physician of rec… | Details → |
| 128 | EOB required The primary carrier's explanation of benefits is necessary to consider t… | Details → |
| 128 | Newborn's services are covered in the mother's Allowance. Start: 02/28/1997 | Details → |
| 128 | Denied. The prescription was written for a condition unrelated to the industrial inju… | Details → |
| 129 | Single HIPPS Effective January 1, 2008, episodes paid under the refined HH PPS will b… | Details → |
| 129 | Prior processing information appears incorrect. At least one Remark Code must be prov… | Details → |
| 129 | Missing or invalid modifier code was billed. Please note corrected code used in this … | Details → |
| 130 | Missing Modifier Please resubmit with appropriate or missing modifier. | Details → |
| 130 | Claim submission fee. Start: 02/28/1997 | Last Modified: 06/30/2001 | Details → |
| 130 | Injured worker name was missing from the billing received by L&I. | Details → |
| 131 | Rendering Provider Rendering Provider Required on Claim | Details → |
| 131 | Claim specific negotiated discount. Start: 02/28/1997 | Details → |
| 131 | Denied. The prescribing provider number is missing or invalid. | Details → |
| 132 | POA Please resubmit with a valid POA code | Details → |
| 132 | Prearranged demonstration project adjustment. Start: 02/28/1997 | Details → |
| 132 | Please list all applicable modifiers in the description field when billing modifier 9… | Details → |
| 133 | SUBMITTED W/O NDC NUMBERS Please resubmit with National Drug Code (NDC) numbers. | Details → |
| 133 | The disposition of this service line is pending further review. (Use only with Group … | Details → |
| 133 | Denied. Gasoline and/or automotive costs are included in the mileage reimbursement ra… | Details → |
| 134 | SUBMITTED W/INVALID NDC #S Please resubmit with a valid National Drug Code (NDC) numb… | Details → |
| 134 | Technical fees removed from charges. Start: 10/31/1998 | Details → |
| 134 | Allowed at rate established by Washington Administrative Code effective this service … | Details → |
| 135 | INVALID NDC NUMBER Please resubmit with a valid National Drug Code (NDC) number. The … | Details → |
| 135 | Interim bills cannot be processed. Start: 10/31/1998 | Last Modified: 09/30/2007 | Details → |
| 135 | Denied. Parking receipts were not attached to your billing. Attach receipts to bill … | Details → |
| 136 | NDC NUMBER(S) ILLEGIBLE Please resubmit this claim with legible NDC numbers. | Details → |
| 136 | Failure to follow prior payer's coverage rules. (Use only with Group Code OA) Start:… | Details → |
| 136 | Extra views must be billed under -22 modifier per Fee Schedule/WAC 296-23-01005. | Details → |
| 137 | FIN and NPI mismatch Our data indicates a FIN and NPI mismatch as billed. Please subm… | Details → |
| 137 | Regulatory Surcharges, Assessments, Allowances or Health Related Taxes. Start: 02/28… | Details → |
| 137 | Procedure code states "minimum of __ views." Additional amount not payable for extra … | Details → |
| 138 | Acute Rehab This is an acute rehab admit. Please resubmit claim with the appropriate … | Details → |
| 138 | Appeal procedures not followed or time limits not met. Start: 06/30/1999 | Last Modi… | Details → |
| 138 | Payment for report not allowed when procedure code billed requires submission of repo… | Details → |
| 139 | OON The benefit for this service is not covered out of network. | Details → |
| 139 | Contracted funding agreement - Subscriber is employed by the provider of services. Us… | Details → |
| 139 | Adjustment processed as result of provider audit. | Details → |
| 140 | Add On Add-on billed without primary code. | Details → |
| 140 | Patient/Insured health identification number and name do not match. Start: 06/30/199… | Details → |
| 140 | Refund made as result of provider audit. | Details → |
| 141 | Drug Coverage Only No Medical Coverage. Member has Drug Coverage Only. | Details → |
| 141 | Claim spans eligible and ineligible periods of coverage. Start: 06/30/1999 | Last Mo… | Details → |
| 141 | Base units paid only. Actual anesthesia time must be on bill. Submit adjustment to th… | Details → |
| 142 | Bundled Service Bundled Service | Details → |
| 142 | Monthly Medicaid patient liability amount. Start: 06/30/2000 | Last Modified: 09/30/… | Details → |
| 142 | Allowable fee set by L&I Medical Consultant based upon review of report. | Details → |
| 143 | HIPPS A HIPPS codes is required for this type of claim. Please resubmit with appropri… | Details → |
| 143 | Portion of payment deferred. Start: 02/28/2001 | Details → |
| 143 | Provider number or NPI corrected to match name. Bill with correct number for provider… | Details → |
| 144 | A8A9 Please resubmit claim with value codes A8 & A9 | Details → |
Medical claim denial codes — formally known as Claim Adjustment Reason Codes (CARC) — are standardized identifiers maintained by the X12 standards body and used across all Medicare, Medicaid, and commercial payer 835 electronic remittance transactions. When a claim is paid at a different amount than billed, at least one CARC code must accompany the remittance advice to indicate the specific reason for the adjustment.
The most frequently encountered codes include CO-16 (missing or invalid claim information), CO-45 (charges exceeding fee schedule), PR-1 (patient deductible), CO-29 (timely filing deadline exceeded), and CO-4 (procedure code inconsistent with modifier). Each represents a distinct, actionable reason that has a defined resolution pathway.