Official X12 description
“Alert: This may involve a question of fact that may be addressed by the appropriate non-medical hearing or adjudicative body.”
Source: X12 Remittance Advice Remark Codes. X12 publishes and maintains the RARC set; always verify against the current release before building a claim workflow.
Paired CARC codes
RARC M4 almost never appears alone — it accompanies one of the CARCs below on the same 835 remittance line. Fix the CARC and the RARC typically clears; the RARC alone is informational.
| Paired CARC | What the CARC means |
|---|---|
| CARC 19 | This is a work-related injury/illness and thus the liability of the Worker's Compensation Carrier. |
What RARC M4 actually means
RARC M4 is an alert pointing to a non-medical hearing venue for disputes (mostly WC and disability). Informational.
Common root causes
- Fact dispute outside medical review.
Prevention checklist
- WC/disability dispute workflow.
Resolution & appeal strategy — step by step
Because RARC M4 is supplemental to a CARC, the resolution path usually starts by fixing the underlying adjustment reason. A formal appeal of the RARC alone is rarely necessary.
- 1Pursue the referenced hearing venue.
Sample reconsideration language referencing RARC M4
Edit the bracketed fields before sending. Payer-specific reconsideration forms are often required — check the provider portal first.
How common is RARC M4?
Platform frequency ranks publish once the anonymized denial-rate pipeline reaches the publication threshold (strategy §12 Phase 2).
How QuickRCM handles RARC M4
QuickRCM reads RARC M4 alongside its paired CARC in the 835 LQ segment and routes the line to the correct worker queue with the right documentation already attached:
- Denial routing rules tuned to the CARC+RARC pair — the paired combination tells QuickRCM which documentation the payer will accept.
- Reconsideration template for this exact remark code pulls the supporting facts from the claim automatically.
- Pre-submission scrubs that catch the preventable drivers surfaced on this page before the 837 leaves the clearinghouse.
Frequently asked questions — RARC M4
What does RARC M4 mean?
RARC M4 is an X12 Remittance Advice Remark Code. The official X12 definition is: "Alert: This may involve a question of fact that may be addressed by the appropriate non-medical hearing or adjudicative body." It is supplemental to a Claim Adjustment Reason Code (CARC) on the same 835 line.
Which CARC is paired with RARC M4?
RARC M4 is most commonly paired with CARC 19. The CARC is the financial adjustment reason; the RARC is the informational remark. Fix the paired CARC first — the RARC usually clears with the corrected claim.
How do I resolve a RARC M4 remark on a remit?
Start from the root cause: Fact dispute outside medical review. First step: Pursue the referenced hearing venue. Because RARCs are supplemental, the resolution is almost always to address the paired CARC rather than appeal the RARC alone.
Where does RARC M4 appear on the 835 ERA?
RARC M4 is carried on the 835 Loop 2110 LQ segment alongside the CARC in the CAS segment of the same service line. The code and its X12 description also print on the paper EOB in the "Remark Code" or "Remark" column next to the corresponding denial or adjustment reason.
Is RARC M4 the same as ICD-10 code M4?
No. RARC M4 is a remittance-advice remark code published by X12 and carried on the 835. Any ICD-10 code with the same letters and digits is a diagnosis code on the 837 HI segment — a completely different code set maintained by the WHO/CMS. Use the transaction context (835 = RARC; 837 = ICD-10) to disambiguate.
Disclaimer
This page is operational reference for medical-billing professionals. It is not legal, clinical, or contractual advice. X12 code descriptors are maintained by the X12 External Code Lists; always verify against the current X12 release and the payer's own published policy before submitting or appealing a claim.