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CARC 201 · CO-201

CARC 201 Denial: Workers' Compensation case settled. Patient is responsible for amount of this c… — How to Fix and Appeal

Reviewed by QuickIntell RCM Editorial Team · Last reviewed

Updated

TL;DR

CARC 201 (X12 Workers' Compensation case settled. Patient is responsible for amount of this claim/service through Workers'…). CARC 201 tells you the Workers' Comp case for this injury has settled and the patient carries the balance through a Medicare Set-Aside (MSA) or similar agreement.

Official X12 description

“Workers' Compensation case settled. Patient is responsible for amount of this claim/service through Workers' Compensation 'Medicare set-aside arrangement' or other agreement.”

Source: X12 Claim Adjustment Reason Codes. The X12 External Code Lists are the single authoritative source for every CARC descriptor — always verify against the current release before building a claim-scrub rule.

What CARC 201 actually means

CARC 201 tells you the Workers' Comp case for this injury has settled and the patient carries the balance through a Medicare Set-Aside (MSA) or similar agreement. Collect from the patient's MSA custodian/trust per the settlement documents.

Common root causes

  • Workers' Comp case settled with a Medicare Set-Aside; Medicare is secondary to the MSA.
  • Settlement agreement makes the patient responsible for post-settlement medical costs.

Prevention checklist

  • Capture the MSA custodian and patient's direct-bill info at registration for any post-settlement WC patient.

Appeal strategy — step by step

Most CARC 201 denials clear faster with the right remediation than with a formal appeal. Work the steps in order and escalate only when a lower-effort path has been ruled out.

  1. 1Rebill the MSA custodian per the settlement documents.
  2. 2Not appealable against the health plan/payer.
Sample appeal-letter language for CARC 201
[Provider letterhead] Re: Appeal of CARC 201 — Claim #{claim_number} Member: {member_name} · Member ID: {member_id} Date(s) of Service: {dos} On {remittance_date} this claim was adjusted with CARC 201: "Workers' Compensation case settled. Patient is responsible for amount of this claim/service through Workers' Compensation 'Medicare set-aside arrangement' or other agreement." We respectfully request reconsideration. The X12 External Code List definition of CARC 201 does not apply to this claim for the following reasons: 1. [Cite the clinical / coding / policy fact that rebuts the adjustment] 2. [Cite the supporting documentation attached — op note, EOB, LCD/NCD citation, NCCI edit indicator, modifier rationale] 3. [Cite the payer's own policy where applicable] Attached: {list supporting documents} Please process payment under the member's benefits. If additional information is required, contact the billing office at {provider_phone} or {provider_email}. Sincerely, {billing_manager_name}, {credentials}

Edit the bracketed fields before sending. This template is a starting point; a payer-specific appeal form may still be required — check the provider portal first.

Payer-specific notes

Payer-specific behavior for CARC 201 publishes here as the QuickIntell anonymized denial ETL ingests sufficient volume. In the meantime, consult the payer directory for the relevant provider manual and appeal form.

How common is CARC 201?

Search demand rank
#98

Out of 306 seeded CARCs, ranked by combined US monthly search volume for "CARC 201", "CO-201 denial", and "denial code 201".

Platform frequency
Pending ETL

Platform frequency ranks publish once the anonymized denial-rate pipeline reaches the publication threshold (strategy §12 Phase 2).

How QuickRCM prevents CARC 201

QuickRCM catches the root causes above before the 837 leaves the clearinghouse:

  • Claim-scrub rules fire on every root cause listed above — the scrub references the same X12 CAS segment logic that drives the denial, so what the payer checks, QuickRCM checks first.
  • When a denial lands, QuickRCM routes it to the correct worker with the documentation bundle already attached (op note, LCD citation, modifier rationale, EOB, primary 835).
  • Appeal templates tuned to each CARC (including this one) pull the supporting facts from the claim and fill the bracketed fields automatically.
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Frequently asked questions — CARC 201

What does CARC 201 mean?

CARC 201 is an X12 Claim Adjustment Reason Code. The official definition is: "Workers' Compensation case settled. Patient is responsible for amount of this claim/service through Workers' Compensation 'Medicare set-aside arrangement' or other agreement." In plain English, the payer is telling you cARC 201 tells you the Workers' Comp case for this injury has settled and the patient carries the balance through a Medicare Set-Aside (MSA) or similar agreement. Collect from the patient's MSA custodian/trust per the settlement documents.

How do I resolve a CARC 201 (CO-201) denial?

Start with the most common root cause: Workers' Comp case settled with a Medicare Set-Aside; Medicare is secondary to the MSA. First step: Rebill the MSA custodian per the settlement documents. See the full remediation and appeal checklist on this page before filing a formal appeal.

Is CARC 201 patient responsibility?

No — CARC 201 is typically carried under CO (Contractual Obligation) or OA (Other Adjustment), which means it is the provider's responsibility, not the patient's. Do not bill the patient unless the 835 CAS group code is PR.

What does CARC 201 look like on an EOB or 835 remittance?

On the 835 ERA, CARC 201 appears in Loop 2110 CAS segment as "CAS*CO*201*{amount}". On a paper EOB the same code prints in the Adjustment/Denial Reason column with the X12 description: "Workers' Compensation case settled. Patient is responsible for amount of this claim/service through Workers' Compensati…" — usually paired with one or more RARC remark codes in the same remittance line for additional context.

Can CARC 201 be appealed successfully?

Yes — when the root cause does not apply to the specific claim. Overturn rates are strongest when the appeal cites the X12 definition, the payer's own published policy, and documentation that rebuts the payer's rationale. The sample appeal language block above is a starting point; always adapt it to the payer's reconsideration form.

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.