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

🚫

Looking for Denial Codes (CARC)?

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

→

Showing 1,301–1,350 of 2,992 remark codes

Remark Code	Description	RA835 Code	Group	Reason Code
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 →
X586	PROTHROMBIN TIME (PT) HAS A MAXIMUM FREQUENCY OF SERVICE UNITS PER FREQUENCY VALUE QUALIFIER	N640 Exceeds number/frequency approved/allowed within time …	CO	151	View →
X587	SERUM IRON STUDIES ARE NOT COVERED BY MEDICARE WITHOUT AN APPROPRIATE DIAGNOSIS	N130 Consult plan benefit documents/guidelines for informat…	CO	204	View →
X588	SERUM IRON STUDIES ARE NOT COVERED BY MEDICARE WHEN BILLED MORE THAN ONCE IN A 90 DAY INTERVAL.	N640 Exceeds number/frequency approved/allowed within time …	CO	151	View →
X589	COLLAGEN CROSSLINKS ARE NOT COVERED BY MEDICARE WHEN BILLED WITHOUT AN APPROPRIATE SUPPORTING DIAGN…	N130 Consult plan benefit documents/guidelines for informat…	CO	204	View →
X59	SERVICE UNIT OUT OF RANGE FOR PROCEDURE (INACTIVE)	M53 Missing/incomplete/invalid days or units of service.	CO	151	View →
X590	GLYCATED HEMOGLOBIN/GLYCATED PROTEIN ARE NOT COVERED BY MEDICARE WHEN BILLED WITHOUT AN APPROPRIATE…	N130 Consult plan benefit documents/guidelines for informat…	CO	204	View →
X591	THYROID TESTING IS NOT COVERED BY MEDICARE WHEN BILLED WITHOUT AN APPROPRIATE SUPPORTING DIAGNOSIS	N130 Consult plan benefit documents/guidelines for informat…	CO	204	View →
X592	DIGOXIN THERAPEUTIC DRUG ASSAY IS NOT COVERED BY MEDICARE WHEN BILLED WITHOUT AN APPROPRIATE SUPPOR…	N130 Consult plan benefit documents/guidelines for informat…	CO	204	View →
X593	ALPHA-FETOPROTEIN IS NOT COVERED BY MEDICARE WHEN BILLED WITHOUT AN APPROPRIATE SUPPORTING DIAGNOSIS	N130 Consult plan benefit documents/guidelines for informat…	CO	204	View →
X594	CARCINOEMBRYONIC ANTIGEN IS NOT COVERED BY MEDICARE WHEN BILLED WITHOUT AN APPROPRIATE SUPPORTING D…	N130 Consult plan benefit documents/guidelines for informat…	CO	204	View →
X595	TUMOR ANTIGEN BY IMMUNOASSAY CA 125 IS NOT COVERED BY MEDICARE WHEN BILLED WITHOUT AN APPROPRIATE S…	N130 Consult plan benefit documents/guidelines for informat…	CO	204	View →
X596	TUMOR ANTIGEN BY IMMUNOASSAY CA 19-9 IS NOT COVERED BY MEDICARE WHEN BILLED WITHOUT AN APPROPRIATE …	N130 Consult plan benefit documents/guidelines for informat…	CO	204	View →
X597	PROSTATE SPECIFIC ANTIGEN IS NOT COVERED BY MEDICARE WHEN BILLED WITHOUT AN APPROPRIATE SUPPORTING …	N130 Consult plan benefit documents/guidelines for informat…	CO	204	View →
X598	PROSTATE SPECIFIC ANTIGEN IS NOT COVERED BY MEDICARE WHEN BILLED MORE THAN ONCE IN A 12 MONTH PERIOD	N640 Exceeds number/frequency approved/allowed within time …	CO	151	View →
X599	GAMMA GLUTAMYL TRANSFERASE IS NOT COVERED BY MEDICARE WHEN BILLED WITHOUT AN APPROPRIATE SUPPORTING…	N130 Consult plan benefit documents/guidelines for informat…	CO	204	View →
X6	ADMISSION DIAGNOSIS DESCRIBES AN EXTERNAL CAUSE OR REQUIRES THE ICD CODE FOR THE FIRST UNDERLYING D…	MA63 Missing/incomplete/invalid principal diagnosis.	CO	16	View →
X60	MULTIPLE BILATERAL PROCEDURES WITHOUT MODIFIER 50	N519 Invalid combination of HCPCS modifiers.	CO	16	View →
X600	HEPATITIS PANEL/ACUTE HEPATITIS PANEL IS NOT COVERED BY MEDICARE WHEN BILLED WITHOUT AN APPROPRIATE…	N130 Consult plan benefit documents/guidelines for informat…	CO	204	View →
X601	ALUMINUM LAB TEST IS NOT COVERED BY MEDICARE WHEN BILLED MORE THAN ONCE WITHIN A 3 MONTH PERIOD	N640 Exceeds number/frequency approved/allowed within time …	CO	151	View →
X602	HEARTSBREATH TEST IS NOT REASONABLE AND NECESSARY AND IS NOT COVERED BY CMS	N130 Consult plan benefit documents/guidelines for informat…	CO	204	View →
X603	BRACHYTHERAPY SOURCES PROCEDURE REQUIRES A VALID BRACHYTHERAPY PROCEDURE.	M84 Medical code sets used must be the codes in effect at …	CO	16	View →
X604	DIRECT ADMISSION OF PATIENT FOR HOSPITAL OBSERVATION CARE WHEN BILLED WITH CRITICAL CARE, EVALUATIO…	N55 Procedures for billing with group/referring/performing…	CO	16	View →
X605	DMEPOS ITEMS BILLED BY A DMEMAC PROVIDER WITH INVALID POS WILL BE DENIED.	M77 Missing/incomplete/invalid/inappropriate place of serv…	CO	5	View →
X606	MANUAL WHEELCHAIR OR WHEELCHAIR-SPECIAL SIZE MUST BE BILLED WITH MODIFIER KX	N572 This procedure is not payable unless appropriate non-p…	CO	16	View →
X607	GLYCATED HEMOGLOBIN/GLYCATED PROTEIN PROCEDURE IS NOT COVERED BY MEDICARE WHEN BILLED MORE THAN ONC…	N640 Exceeds number/frequency approved/allowed within time …	CO	151	View →

📋

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.

🔗

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.

⚡

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.