Remark Codes — Complete List & Lookup

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.

2,992

Total Remark Codes

Adjustment Groups

835

RA835 Mapped

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Looking for Denial Codes (CARC)?

Browse Claim Adjustment Reason Codes — the codes that explain why a payment was reduced or denied.

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Showing 1,151–1,200 of 2,818 remark codes in group CO

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Remark Code	Description	RA835 Code	Group	Reason Code
X520	Procedure code must be billed with Place of Service 55.	M77 Missing/incomplete/invalid/inappropriate place of serv…	CO	16	View →
X521	SERIES BILL REVENUE CODE REQUIRED	M50 Missing/incomplete/invalid revenue code(s).	CO	16	View →
X522	PER MEDICAID GUIDELINES, THIS PROCEDURE QUALIFIES FOR A MULTIPLE ENDOSCOPY REDUCTION AND PAYMENT SH…	—	CO	203	View →
X53	NON-COVERED UNDER ANY MEDICARE OUTPATIENT BENEFIT, FOR REASONS OTHER THAN STATUTORY EXCLUSION	N174 This is not a covered service/procedure/ equipment/bed…	CO	96	View →
X539	Inpatient Principal Hospital Acquired Condition	—	CO	233	View →
X54	SERVICE SUBMITTED FOR DENIAL (CONDITION CODE 21)	M44 Missing/incomplete/invalid condition code.	CO	16	View →
X540	INPATIENT OTHER HOSPITAL ACQUIRED CONDITION	—	CO	233	View →
X546	THIS LINE ITEM CONFLICTS WITH CCI EDIT POLICY.	—	CO	16	View →
X547	DME CODE BILLED WITH INVALID MODIFIER.	N572 This procedure is not payable unless appropriate non-p…	CO	4	View →
X548	PAYMENT FOR DISCONTINUED PROCEDURES IS BASED ON PERCENTAGE OF SERVICE COMPLETED. PLEASE SUBMIT MED…	N204 Services under review for possible pre-existing condit…	CO	163	View →
X549	AB CODE IS PART OF AN AUTOMATED PANEL. REIMBURSEMENT IS A PERCENTAGE OF MPFS ALLOWABLE.	N381 Alert: Consult our contractual agreement for restricti…	CO	144	View →
X55	SERVICE SUBMITTED FOR FI/MAC REVIEW (CONDITION CODE 20)	M44 Missing/incomplete/invalid condition code.	CO	16	View →
X550	FX MODIFIER (FILM XRAY) HAS A 20% REDUCTION OF THE TC (AND THE TC OF THE GLOABEL FEE) EFFECTIVE 1/1…	N546 Payment represents a previous reduction based on the E…	CO	45	View →
X551	THIS IS A DUPLICATE LINE ITEM	N522 Duplicate of a claim processed, or to be processed, as…	CO	18	View →
X552	SUPPLIES FURNISHED BY COMPREHENSIVE OUTPATIENT REHABILITATION FACILITIES (CORFS) OR OUTPATIENT PHYS…	M15 Separately billed services/tests have been bundled as …	CO	97	View →
X553	(CERCLAGE REMOVAL) WILL BE DENIED AS INCLUDED IN THE DELIVERY FEE, WHEN THE REMOVAL OF A CERCLAGE I…	N55 Procedures for billing with group/referring/performing…	CO	16	View →
X554	PROCEDURE CODE REQUIRES ICD-10 Z00.6 ALSO BE BILLED ON THE CLAIM.	M76 Missing/incomplete/invalid diagnosis or condition.	CO	16	View →
X555	DME CODE BILLED WITH MODIFIER WILL BE DENIED BECAUSE SAME EQUIPMENT HAS BEEN PURCHASED WITHIN PAST …	N417 This service is allowed 1 time in a 5-year period.	CO	119	View →
X556	(STERILE SALINE) BILLED WITH ORORPHARYNGEAL SUCTION CATHETER WHEN A TRACHEAL SUCTION CATHETER HAS N…	N381 Alert: Consult our contractual agreement for restricti…	CO	169	View →
X557	(MASTECTOMY BRA) WILL BE DENIED IF BREAST PROSTHESIS HAS NOT BEEN BILLED WITHIN THE PREVIOUS TWO (2…	N381 Alert: Consult our contractual agreement for restricti…	CO	16	View →
X558	() IS DENIED BECAUSE THE SAME PROCEDURE HAS BEEN RENDERED TO THE MEMBER ON WITHIN THE PREVIOUS FIVE…	N640 Exceeds number/frequency approved/allowed within time …	CO	151	View →
X559	(DME REPAIR) IS DENIED BECAUSE THE MEMBER HAS DURABLE MEDICAL EQUIPMENT PURCHASE ON THE SAME SERVIC…	M86 Service denied because payment already made for same/s…	CO	16	View →
X560	(DME REPAIR) IS DENIED BECAUSE IT WAS BILLED WITH A FREQUENTLY SERVICED RENTAL ITEM APPENDED WITH M…	MA114 Missing/incomplete/invalid information on where the se…	CO	16	View →
X561	(POWER WHEELCHAIR ACCESSORY) IS DENIED BECAUSE POWER WHEELCHAIR WAS NOT FOUND IN CLAIM HISTORY WITH…	MA114 Missing/incomplete/invalid information on where the se…	CO	151	View →
X562	STATIONARY OXYGEN SYSTEM IS NOT COVERED BY CMS WHEN BILLED MORE THAN ONCE WITHIN THE SAME MONTH.	N640 Exceeds number/frequency approved/allowed within time …	CO	151	View →
X563	PORTABLE OXYGEN SYSTEM IS NOT COVERED BY CMS WHEN BILLED MORE THAN ONCE WITHIN THE SAME MONTH.	N640 Exceeds number/frequency approved/allowed within time …	CO	151	View →
X564	OXYGEN ACCESSORY IS NOT COVERED BY CMS WHEN BILLED WITH OXYGEN RENTAL SYSTEM ON THE SAME MONTH.	N640 Exceeds number/frequency approved/allowed within time …	CO	151	View →
X565	STATIONARY OXYGEN CONTENTS IS NOT COVERED BY CMS WHEN BILLED WITH STATIONARY OXYGEN RENTAL SYSTEM O…	N640 Exceeds number/frequency approved/allowed within time …	CO	151	View →
X566	NEBULIZER IS NOT COVERED IF BILLED MORE THAN ONCE EVERY MONTHS	N640 Exceeds number/frequency approved/allowed within time …	CO	151	View →
X567	RESPIRATORY ASSIST DEVICE IS NOT COVERED IF BILLED MORE THAN ONCE EVERY MONTHS	N640 Exceeds number/frequency approved/allowed within time …	CO	151	View →
X568	TENS DEVICE IS NOT COVERED BY CMS AS A PURCHASE IF IT HAS NOT BEEN BILLED WITH A RENTAL MODIFIER (R…	N640 Exceeds number/frequency approved/allowed within time …	CO	151	View →
X569	TENS SUPPLIES ARE NOT COVERED BY CMS BECASE A TENS DEVICE WAS BILLED ON ANOTHER CLAIM.	N522 Duplicate of a claim processed, or to be processed, as…	CO	18	View →
X57	SEPARATE PAYMENT FOR SERVICES IS NOT PROVIDED BY MEDICARE	—	CO	242	View →
X570	TENS SUPPLIES ARE NOT COVERED BY CMS BECAUSE "A4595" WAS BILLED ON ANOTHER CLAIM.	N381 Alert: Consult our contractual agreement for restricti…	CO	16	View →
X571	REPLACEMENT LEAD WIRES ARE NOT COVERED BY CMS BECAUSE A TENS DEVICE WAS BILLED ON ANOTHER CLAIM.	N381 Alert: Consult our contractual agreement for restricti…	CO	272	View →
X572	PRESSURE REDUCING SUPPORT SURFACE IS NOT COVERED BY CMS WHEN BILLED MORE THAN ONCE WITHIN THE SAME …	N640 Exceeds number/frequency approved/allowed within time …	CO	151	View →
X573	ORTHOSES ADDITION CODES ARE NOT ELIGIBLE FOR SEPARATE PAYMENT.	N15 Services for a newborn must be billed separately.	CO	97	View →
X574	ORTHOSES ADDITION CODES ARE INCLUDED IN PRIMARY PROCEDURE.	M75 Multiple automated multichannel tests performed on the…	CO	236	View →
X575	E/M PROCEDURE WAS BILLED ON THE SAME DATE OF SERVICE WITH CARDIOVASCUALR SERVICE WITHOUT AN APPROPR…	N572 This procedure is not payable unless appropriate non-p…	CO	16	View →
X576	E/M PROCEDURE WAS BILLED ON THE SAME DATE OF SERVICE WITH CARDIOVASCUALR SERVICE ON HISTORY CLAIM ,…	N13 Payment based on professional/technical component modi…	CO	16	View →
X577	VERTEBRAL AXIAL DECOMPRESSION, PER SESSION, IS A NON-COVERED SERVICE.	N130 Consult plan benefit documents/guidelines for informat…	CO	204	View →
X578	HAIR ANALYSIS IS A NON-COVERED SERVICE.	N130 Consult plan benefit documents/guidelines for informat…	CO	204	View →
X579	BACTERIAL URINE CULTURE IS NOT COVERED BY MEDICARE	N130 Consult plan benefit documents/guidelines for informat…	CO	204	View →
X58	CODE INDICATES A SITE OF SERVICE NOT INCLUDED IN OPPS	N130 Consult plan benefit documents/guidelines for informat…	CO	96	View →
X580	HUMAN IMUNODEFICIENCY VIRUS (HIV) TESTING IS NOT COVERED BY MEDICARE	N130 Consult plan benefit documents/guidelines for informat…	CO	204	View →
X581	HUMAN IMMUNODEFICIENCY VIRUS (HIV) TESTING (PROGNOSIS INCLUDING MONITORING) IS NOT COVERED BY MEDIC…	N130 Consult plan benefit documents/guidelines for informat…	CO	204	View →
X582	BLOOD COUNTS TESTING IS NOT COVERED BY MEDICARE WHEN BILLED WITH UNSUPPORTED DIAGNOSIS	N130 Consult plan benefit documents/guidelines for informat…	CO	204	View →
X583	PARTIAL THROMBOPLASTIN TIME (PTT) IS NOT COVERED BY MEDICARE WHEN BILLED WITHOUT SUPPORTING DIAGNOS…	N130 Consult plan benefit documents/guidelines for informat…	CO	204	View →
X584	PROTHROMBIN TIME (PT) IS NOT COVERED BY MEDICARE WHEN BILLED WITHOUT SUPPORTING DIAGNOSIS	N130 Consult plan benefit documents/guidelines for informat…	CO	204	View →
X585	PROCEDURE HAS A MAXIMUM FREQUENCY OF SERVICES	N640 Exceeds number/frequency approved/allowed within time …	CO	151	View →

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What is a Remark Code?

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.

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Remark Code vs. Denial Code

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.

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How to Use This List

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.