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 1,251–1,300 of 2,818 remark codes in group CO

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Remark Code	Description	RA835 Code	Group	Reason Code
X630	PER CMS POLICY, PROCEDURE CODE DESCRIBES HYPERTHERMIA SERVICES WHICH ARE ONLY COVERED WHEN BILLED I…	M84 Medical code sets used must be the codes in effect at …	CO	16	View →
X631	(HOSPITAL DISCHARGE SERVICES) WAS BILLED ON PRIOR DAY ON CLAIM.	N522 Duplicate of a claim processed, or to be processed, as…	CO	18	View →
X632	CO-SURGEONS COULD BE PAID, THOUGH SUPPORTING DOCUMENTATION IS REQUIRED TO ESTABLISH THE MEDICAL NEC…	N706 Missing documentation.	CO	163	View →
X633	PER THE MEDICARE PHYSICIAN FEE SCHEDULE, PROCEDURE CODE DESCRIBES A PHYSICIAN INTERPRETATION FOR SE…	M77 Missing/incomplete/invalid/inappropriate place of serv…	CO	5	View →
X634	PER CMS GUIDELINES, CO-SURGEON CLAIMS WHEN BOTH SURGEONS HAVE THE SAME SUBSPECIALTY FOR PROCEDURES …	N130 Consult plan benefit documents/guidelines for informat…	CO	204	View →
X635	PER AMA GUIDELINES, INITIAL HOSPITAL OR BIRTHING CENTER CARE WILL BE DENIED WHEN THE NEWBORN HAS RE…	M84 Medical code sets used must be the codes in effect at …	CO	16	View →
X64	CODE2 OF A CODE PAIR THAT IS NOT ALLOWED BY NCCI EVEN IF APPROPRIATE MODIFIER IS PRESENT	M86 Service denied because payment already made for same/s…	CO	97	View →
X644	PROCEDURE LINE IS A POSSIBLE DUPLICATE OF CLAIM. PROCEDURE CAN NOT BE BILLED ON SAME DOS WITH DIFFE…	N522 Duplicate of a claim processed, or to be processed, as…	CO	18	View →
X645	INJECTIONS, LABS REPORTS, AND TESTS MUST BE BILLED WITH SPECIFIC PROCEDURE CODE ON ONE SERVICE SECT…	N381 Alert: Consult our contractual agreement for restricti…	CO	16	View →
X646	THERAPY MUST BE BILLED WITH ONE SERVICE SECTION FOR EACH ITEM (PT, OT OR ST) OR SERVICE PROVIDED TO…	N381 Alert: Consult our contractual agreement for restricti…	CO	272	View →
X647	MODIFIER 25/59 CAN NOT BE BILLED MULTIPLE TIMES FOR THE SAME SERVICE RENDERED ON THE SAME DOS.	N130 Consult plan benefit documents/guidelines for informat…	CO	272	View →
X648	PRICING MODIFIERS SHOULD NOT BE SUBMITTED MULTIPLE TIMES ON THE SAME PROCEDURE.	N130 Consult plan benefit documents/guidelines for informat…	CO	272	View →
X649	IMPROPER BILLING OF BILATERAL PROCEDURE. UNITS MUST BE 1.	M53 Missing/incomplete/invalid days or units of service.	CO	222	View →
X65	MEDICAL VISIT ON THE SAME DAY AS A TYPE T OR S PROCEDURE WITHOUT MODIFIER 25	N519 Invalid combination of HCPCS modifiers.	CO	16	View →
X650	AUDIOLOGY INPATIENT CHARGES ARE INCLUDED IN THE REIMBURSEMENT TO A HOSPITAL AND ARE NOT TO BE BILLE…	N130 Consult plan benefit documents/guidelines for informat…	CO	272	View →
X651	PROVIDER TAXONOMY CANNOT BILL IN PLACE OF SERVICE .	N288 Missing/incomplete/invalid rendering provider taxonomy.	CO	8	View →
X652	DME SUPPLIERS CANNOT BILL IN PLACE OF SERVICE WHEN THE PATIENT IS 21 YEARS OR OLDER.	M77 Missing/incomplete/invalid/inappropriate place of serv…	CO	5	View →
X653	REVENUE CODE INVALID FOR CATEGORY OF SERVICE.	M50 Missing/incomplete/invalid revenue code(s).	CO	16	View →
X654	OCCURRENCE CODE 50 IS NO LONGER VALID TO BYPASS PA FOR POST-DISCHARGE SERVICES. OCCURRENCE CODE 42 …	M45 Missing/incomplete/invalid occurrence code(s).	CO	16	View →
X655	PROCEDCURE CODE CAN ONLY BE USED BY OUTPATIENT FACILITIES BILLED ON AN INSTUTIONAL CLAIM (C CODES)	M51 Missing/incomplete/invalid procedure code(s).	CO	16	View →
X656	WHEN MULTIPLE GENERAL ANESTHESIA SERVICE CODES, ONLY THE HIGHEST SUBMITTED CHARGE AMOUNT WILL BE PA…	N634 The allowance is calculated based on anesthesia time u…	CO	59	View →
X657	INCORRECT BILLING OF ASSISTANT SURGEON MODIFIERS FOR CRITICAL ACCESS PROFESSIONAL FEES REVENUE CODE…	N130 Consult plan benefit documents/guidelines for informat…	CO	272	View →
X658	INCORRECT BILLING OF CO-SURGEON MODIFIER FOR CRITICAL ACCESS PROFESSIONAL FEES REVENUE CODE.; REVEN…	N130 Consult plan benefit documents/guidelines for informat…	CO	272	View →
X659	C CODES CANNOT BE BILLED WITH REVENUE CODES REPRESENTING PROFESSIONAL FEES; REVENUE CODES 0960-0989.	N130 Consult plan benefit documents/guidelines for informat…	CO	272	View →
X66	INVALID MODIFIER	N519 Invalid combination of HCPCS modifiers.	CO	182	View →
X660	DENY ROOM AND BOARD REVENUE CODES WHEN BILLED IN AN OUTPATIENT HOSPITAL SETTING.	N676 Service does not qualify for payment under the Outpati…	CO	60	View →
X661	MEDICAL/SURGICAL SUPPLIES AND DME CANNOT BE BILLED WITH PROFESSIONAL FEE REVENUE CODES (0960-0989) …	N130 Consult plan benefit documents/guidelines for informat…	CO	272	View →
X662	FACILITY SHOULD NOT BILL OP CLAIM.	N676 Service does not qualify for payment under the Outpati…	CO	60	View →
X663	FACILITY SHOULD NOT BILL IP CLAIM.	N130 Consult plan benefit documents/guidelines for informat…	CO	272	View →
X664	PROSTHESIS BILLED WITH MODIFIER K0 OR KO WILL BE DENIED.	N657 This should be billed with the appropriate code for th…	CO	4	View →
X665	DME IS NOT ON THE CAPPED RENTAL LIST AND CANNOT BE BILLED WITH A RENTAL MODIFIER	N519 Invalid combination of HCPCS modifiers.	CO	16	View →
X666	PROSTHESIS AND ORTHOSIS MUST BE BILLED WITH MODIFIERS LT OR RT	N519 Invalid combination of HCPCS modifiers.	CO	16	View →
X667	CAPPED DME RENTAL IS NOT COVERED BY MEDICARE WHEN BILLED WITHOUT AN APPROPRIATE MODIFIER(RR,KI,KH O…	N519 Invalid combination of HCPCS modifiers.	CO	16	View →
X668	DME SERVICE IS NOT COVERED BY CMS AS A RENTAL OR A PURCHASE WHEN THE ITEM HAS PREVIOUSLY BEEN PAID …	N522 Duplicate of a claim processed, or to be processed, as…	CO	18	View →
X669	WHEEL CHAIR OR ACCESSORY IS NOT COVERED BY MEDICARE WHEN BILLED WITHOUT AN APPROPRIATE MODIFIER (KX)	N657 This should be billed with the appropriate code for th…	CO	4	View →
X67	INVALID DATE	N301 Missing/incomplete/invalid procedure date(s).	CO	16	View →
X670	CUSHIONS AND POSITIONING ACCESSORIES IS NOT COVERED BY MEDICARE WHEN BILLED WITHOUT AN APPROPRIATE …	N657 This should be billed with the appropriate code for th…	CO	4	View →
X671	HOSPITAL BED OR ACCESSORY IS NOT COVERED BY MEDICARE WHEN BILLED WITHOUT AN APPROPRIATE MODIFIER (K…	N657 This should be billed with the appropriate code for th…	CO	4	View →
X672	TOTAL ELECTRIC HOSPITAL BED IS NOT COVERED BY MEDICARE	N130 Consult plan benefit documents/guidelines for informat…	CO	96	View →
X673	WHEEL CHAIR OR ACCESSORY IS NOT COVERED BY MEDICARE WHEN BILLED WITHOUT AN APPROPRIATE MODIFIER (KX)	N657 This should be billed with the appropriate code for th…	CO	4	View →
X674	OXYGEN OR OXYGEN EQUIPMENT IS NOT COVERED WHEN BILLED MORE THAN ONCE PER MONTH	N640 Exceeds number/frequency approved/allowed within time …	CO	151	View →
X675	OXYGEN RENTAL EQUIPMENT CPT IS NOT COVERED BY CMS WHEN BILLED WITHOUT RENTAL MODIFIER RR	N657 This should be billed with the appropriate code for th…	CO	4	View →
X676	LARGE VOLUME ULTRASONIC NEBULIZER/ACCESSORIES ARE NOT COVERED BY CMS	N130 Consult plan benefit documents/guidelines for informat…	CO	96	View →
X677	RESPIRATORY ASSIST DEVICE IS NOT COVERED WHEN BILLED WITHOUT MODIFIER KX	N657 This should be billed with the appropriate code for th…	CO	4	View →
X678	EXTERNAL INFUSION PUMP/ADMINISTRATION IS NOT COVERED WHEN BILLED WITHOUT MODIFIER KX	N657 This should be billed with the appropriate code for th…	CO	4	View →
X679	EXTERNAL INFUSION PUMPS ARE NOT COVERED WHEN BILLED WITHOUT MODIFIER KX	N657 This should be billed with the appropriate code for th…	CO	4	View →
X68	DATE OUT OF OCE RANGE	M53 Missing/incomplete/invalid days or units of service.	CO	16	View →
X680	COMMODE MUST BE BILLED WITH MODIFIER KX	N657 This should be billed with the appropriate code for th…	CO	4	View →
X681	SPEECH GENERATING DEVICE MUST BE BILLED WITH MODIFIER KX	N657 This should be billed with the appropriate code for th…	CO	4	View →
X682	HIGH FREQUENCY CHEST WALL OSCILLATION DEVICE MUST BE BILLED WITH MODIFIER KX	N657 This should be billed with the appropriate code for th…	CO	4	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.