CARC — Claim Adjustment Reason Codes

CARCs appear in the 835 remittance advice CAS segment and tell you why the payer paid less than the billed amount — bundling, medical necessity, prior-auth gaps, timely-filing, patient responsibility, and contractual adjustments. 306 codes seeded, ordered by US search demand. Every leaf page cites the official X12 description and pairs the RARC partners typically observed on the 835. Source: X12 External Code Lists.

Reviewed by QuickIntell Editorial Team · Last reviewed April 23, 2026

Updated Apr 23, 2026

All CARCs306 Bundling / NCCI8 Coding / modifier18 Medical necessity8 Prior authorization15 Coverage / eligibility29 Timely filing2 Patient responsibility20 Duplicate2 Contractual21 Other183

Showing 15 of 306 CARCs in Prior authorization.

Rank	Code	Description (X12)	Category	US search / mo
#11	CARC 197	Precertification/authorization/notification/pre-treatment absent.	Prior authorization	370
#25	CARC 243	Services not authorized by network/primary care providers.	Prior authorization	140
#41	CARC 288	Referral absent.	Prior authorization	70
#64	CARC 284	Precertification/authorization/notification/pre-treatment number may be valid but does not apply to the billed services.	Prior authorization	40
#84	CARC 15	The authorization number is missing, invalid, or does not apply to the billed services or provider.	Prior authorization	20
#87	CARC 136	Failure to follow prior payer's coverage rules.	Prior authorization	20
#102	CARC 287	Referral exceeded.	Prior authorization	10
#103	CARC 302	Precertification/notification number provided is no longer valid.	Prior authorization	10
#153	CARC 210	Payment adjusted because pre-certification/authorization not received in a timely fashion.	Prior authorization	—
#163	CARC 53	Services by an immediate relative or a member of the same household are not covered.	Prior authorization	—
#184	CARC 148	Information from another provider was not provided or was insufficient/incomplete.	Prior authorization	—
#210	CARC 213	Non-compliance with the physician self referral prohibition legislation or payer policy.	Prior authorization	—
#243	CARC 274	Fee/Service not payable per patient Care Coordination arrangement.	Prior authorization	—
#256	CARC 296	Precertification/notification number does not apply to the specified provider.	Prior authorization	—
#291	CARC P17	Referral not authorized by attending physician per regulatory requirement.	Prior authorization	—

Paired with a RARC?

Most CARCs arrive on the 835 alongside one or more Remittance Advice Remark Codes that narrow the reason. See the RARC remark-code reference for the paired explanations.

CARC — Claim Adjustment Reason Codes

Filter by root-cause category

Paired with a RARC?