Browse all standardized Remark Codes (RARC) used on Medicare, Medicaid, and commercial payer remittance advice (835 ERA / EOB). Each code includes its RA835 mapping, adjustment group, reason code, and a dedicated resolution guide.
Browse Claim Adjustment Reason Codes — the codes that explain why a payment was reduced or denied.
| Remark Code | Description | RA835 Code | Group | Reason Code | |
|---|---|---|---|---|---|
| X106 | CODE NOT RECOGNIZED BY OPPS; ALTERNATE CODE FOR SAME SERVICE MAY BE AVAILABLE |
M51
Missing/incomplete/invalid procedure code(s). |
CO | 16 | View → |
| X107 | THIS OT CODE ONLY BILLED ON PARTIAL HOSPITALIZATION CLAIMS |
M51
Missing/incomplete/invalid procedure code(s). |
CO | 16 | View → |
| X108 | AT SERVICE NOT PAYABLE OUTSIDE THE PARTIAL HOSPITALIZATION PROGRAM |
M51
Missing/incomplete/invalid procedure code(s). |
CO | 16 | View → |
| X109 | REVENUE CODE NOT RECOGNIZED BY MEDICARE |
M50
Missing/incomplete/invalid revenue code(s). |
CO | 16 | View → |
| X11 | PRINCIPAL DIAGNOSIS IS NOT TYPICAL FOR A PATIENT OF THIS AGE. |
N129
Not eligible due to the patient's age. |
CO | 6 | View → |
| X110 | CODE REQUIRES MANUAL PRICING |
N10
Adjustment based on the findings of a review organizat… |
CO | 144 | View → |
| X111 | SERVICE PROVIDED PRIOR TO FDA APPROVAL | — | CO | 188 | View → |
| X112 | SERVICE PROVIDED PRIOR TO DATE OF NATIONAL COVERAGE DETERMINATION (NCD) APPROVAL |
N386
This decision was based on a National Coverage Determi… |
CO | 96 | View → |
| X113 | SERVICE PROVIDED OUTSIDE APPROVAL PERIOD |
N351
Service date outside of the approved treatment plan se… |
CO | 96 | View → |
| X114 | CA MODIFIER REQUIRES PATIENT STATUS CODE 20 |
N657
This should be billed with the appropriate code for th… |
CO | 16 | View → |
| X115 | CLAIM LACKS REQUIRED DEVICE CODE |
N657
This should be billed with the appropriate code for th… |
CO | 16 | View → |
| X116 | SERVICE NOT BILLABLE TO THE FISCAL INTERMEDIARY/MEDICARE ADMINISTRATIVE CONTRACTOR |
N479
Missing Explanation of Benefits (Coordination of Benef… |
CO | 163 | View → |
| X117 | INCORRECT BILLING OF BLOOD AND BLOOD PRODUCTS |
M51
Missing/incomplete/invalid procedure code(s). |
CO | 16 | View → |
| X118 | UNITS GREATER THAN ONE FOR BILATERAL PROCEDURE BILLED WITH MODIFIER 50 |
N644
Reimbursement has been made according to the bilateral… |
CO | 59 | View → |
| X119 | INCORRECT BILLING OF MODIFIER FB OR FC |
N572
This procedure is not payable unless appropriate non-p… |
CO | 16 | View → |
| X12 | OTHER DIAGNOSIS IS NOT TYPICAL FOR A PATIENT OF THIS AGE. |
N129
Not eligible due to the patient's age. |
CO | 9 | View → |
| X120 | TRAUMA RESPONSE CRITICAL CARE CODE WITHOUT REVENUE CODE 068X AND CPT 99291 |
M51
Missing/incomplete/invalid procedure code(s). |
CO | 16 | View → |
| X121 | CLAIM LACKS ALLOWED PROCEDURE CODE |
M20
Missing/incomplete/invalid HCPCS. |
CO | 16 | View → |
| X122 | CLAIM LACKS REQUIRED RADIOLABELED PRODUCT |
M51
Missing/incomplete/invalid procedure code(s). |
CO | 16 | View → |
| X123 | INCORRECT BILLING OF REVENUE CODE WITH HCPCS CODE |
N174
This is not a covered service/procedure/ equipment/bed… |
CO | 199 | View → |
| X124 | MENTAL HEALTH CODE NOT APPROVED FOR PARTIAL HOSPITALIZATION | — | CO | 96 | View → |
| X125 | MENTAL HEALTH SERVICE NOT PAYABLE OUTSIDE THE PARTIAL HOSPITALIZATION PROGRAM | — | CO | 96 | View → |
| X126 | CHARGE EXCEEDS TOKEN CHARGE ($1.01) |
N640
Exceeds number/frequency approved/allowed within time … |
CO | 119 | View → |
| X127 | SERVICE PROVIDED ON OR AFTER EFFECTIVE DATE OF NCD NON-COVERAGE |
N30
Patient ineligible for this service. |
CO | 27 | View → |
| X128 | Claim lacks required primary code | — | CO | 16 | View → |
| X129 | Claim lacks required device code or required procedure code |
M51
Missing/incomplete/invalid procedure code(s). |
CO | 16 | View → |
| X13 | ADMISSION DIAGNOSIS IS NOT TYPICAL FOR A PATIENT OF THIS GENDER. | — | CO | 10 | View → |
| X130 | Manifestation code not allowed as principal diagnosis |
MA66
Missing/incomplete/invalid principal procedure code. |
CO | 16 | View → |
| X131 | Skin substitute application procedure without appropriate skin substitute product code |
M51
Missing/incomplete/invalid procedure code(s). |
CO | 16 | View → |
| X132 | payment code not reported for FQHC claim |
M79
Missing/incomplete/invalid charge. |
CO | 16 | View → |
| X133 | FQHC claim lacks required qualifying visit code |
M51
Missing/incomplete/invalid procedure code(s). |
CO | 16 | View → |
| X134 | Incorrect revenue code reported for FQHC payment code |
M51
Missing/incomplete/invalid procedure code(s). |
CO | 16 | View → |
| X135 | Item or service not covered under FQHC PPS | — | CO | 96 | View → |
| X136 | Device-dependent procedure reported without device code |
M51
Missing/incomplete/invalid procedure code(s). |
CO | 16 | View → |
| X137 | PER MEDICARE'S UNLIKELY EDITS POLICY, THE UNITS OF SERVICE BILLED FOR THE PROCEDURE EXCEEDS THE ALL… |
N362
The number of Days or Units of Service exceeds our acc… |
CO | 45 | View → |
| X138 | Item or service expected to be denied as not reasonable and necessary. |
N227
Incomplete/invalid Certificate of Medical Necessity. |
CO | 50 | View → |
| X139 | MULTIPLE MEDICAL VISITS (BASED ON UNITS AND/OR LINES) ARE PRESENT ON THE SAME DAY WITH THE SAME REV… |
M86
Service denied because payment already made for same/s… |
CO | 16 | View → |
| X14 | PRINCIPAL DIAGNOSIS IS NOT TYPICAL FOR A PATIENT OF THIS GENDER. |
N517
Resubmit a new claim with the requested information. |
CO | 10 | View → |
| X142 | THE HISTORICAL PROCEDURE CODE SHOULD BE REVIEWED FOR A POTENTIAL MULTIPLE PROCEDURE REDUCTION. |
M15
Separately billed services/tests have been bundled as … |
CO | 59 | View → |
| X143 | This service is not appropriate for medicare patients in an ambulatory surgery center setting |
M77
Missing/incomplete/invalid/inappropriate place of serv… |
CO | 5 | View → |
| X144 | Service does not meet the guidelines for TOB 14x. |
N381
Alert: Consult our contractual agreement for restricti… |
CO | 59 | View → |
| X146 | The surgical procedure code has been crosswalked to an anesthesia procedure code for analysis of th… | N29 | CO | 16 | View → |
| X147 | THE PROCEDURE WAS BILLED BY A PROVIDER NOT LISTED AS AN ANESTHESIOLOGY PROVIDER. |
N95
This provider type/provider specialty may not bill thi… |
CO | 8 | View → |
| X148 | AN ANESTHESIA SERVICE WITH AN EQUAL OR HIGHER BASE UNIT VALUE WAS BILLED ON PREVIOUS CLAIM. ONLY TH… | — | CO | 59 | View → |
| X149 | HISTORICAL - AN ANESTHESIA SERVICE WITH AN EQUAL OR HIGHER BASE UNIT VALUE WAS BILLED ON A PREVIOU… |
N381
Alert: Consult our contractual agreement for restricti… |
CO | 59 | View → |
| X15 | OTHER DIAGNOSIS IS NOT TYPICAL FOR A PATIENT OF THIS GENDER. |
N517
Resubmit a new claim with the requested information. |
CO | 10 | View → |
| X150 | THE SYSTEM WAS UNABLE TO CROSSWALK THE SURGICAL CODE TO AN ANESTHESIA CODE SINCE THE ANESTHESIA CRO… |
M51
Missing/incomplete/invalid procedure code(s). |
CO | 16 | View → |
| X151 | THE PROCEDURE CODE REQUIRES A CROSSWALK TO AN ANESTHESIA CODE PRIOR TO EDITING. REPLACE THE SURGIC… | N29 | CO | 16 | View → |
| X152 | ANESTHESIA MODIFIER REDUCTION POLICY (THE MODIFIER ON THIS CLAIM LINE INDICATES THE SERVICE SHOULD … | — | CO | 144 | View → |
| X153 | ANESTHESIA CODE ON THIS LINE REQUIRES AN APPROPRIATE MODIFIER. |
N13
Payment based on professional/technical component modi… |
CO | 4 | View → |
Remark Codes (RARC) are used on the 835 ERA and paper EOB to provide supplemental information about a claim adjustment. They always accompany a CARC (denial code) and clarify the reason for payment differences.
A Denial Code (CARC) explains why payment was adjusted. A Remark Code (RARC) provides additional context or instructions. Both appear together on remittance — look for the CARC first, then the RARC for detail.
Search by code number or keyword, or filter by adjustment group (CO, PR, OA…). Click any code to see its full RA835 mapping, common causes, step-by-step resolution guide, and appeal tips.