Remark code (RARC)
Updated September 30, 2026
Definition
A code on a claim decision that adds detail about why a claim was paid, reduced, or denied. Remark codes work alongside claim adjustment reason codes.
A remark code adds detail to a claim decision. Its full name is remittance advice remark code (RARC). It works with a claim adjustment reason code, which gives the main reason a claim was paid differently than it was billed. The remark code explains more.
Standard remark codes start with letters, usually M, MA, or N, followed by numbers. Some explain an adjustment. Others are alerts. For example, N1 says you may appeal the decision in writing within the time limits. On your explanation of benefits (EOB), your plan may show its own short code with a plain-language note instead.
Remark codes can point you to the fix. A note about missing information may mean the provider needs to correct the claim and send it again. Our guide to denial codes on your EOB explains the most common ones.
Related terms
Guides that use this term
- GuideDenial codes on your EOB, explainedWhat do CO-45, PR-1, and CO-16 mean? Look up common claim denial codes, learn who's responsible for each amount, and see what to do about each one.
- GuideInsurance didn't pay my medical bill: what to do nextInsurance didn't pay your medical bill? Find out why, match the denial code to the fix, and learn when to ask for a rebill and when to file an appeal.
Sources
- Remittance advice remark codes, X12. Accessed September 30, 2026.
- Reading your explanation of benefits (EOB), Centers for Medicare & Medicaid Services. Accessed September 30, 2026.
This is general information, not legal or medical advice. Rules can depend on your plan and your state. Romi Care isn't an insurer, law firm, collection agency, or government program.