Official X12 description
“This service/equipment/drug is not covered under the patient's current benefit plan.”
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 204 actually means
CARC 204 is a benefit-plan exclusion denial — the specific service, equipment, or drug is not in the patient's plan benefits. This is similar to CARC 96 but more often applied to pharmacy, DME, and tier-specific commercial benefits. Usually not appealable unless there is an error in how the plan was applied; the remedy is to move the balance to the patient after ABN/financial-responsibility, or to identify whether a different benefit category (e.g., pharmacy vs. medical benefit) applies.
Common root causes
- Service is a plan-document exclusion.
- Drug is not on the plan's formulary, or is on a tier the patient's plan does not cover.
- DME item requires a specific benefit rider the patient did not elect.
- Service is covered under a carve-out (pharmacy benefit manager, behavioral health) that was not billed.
Prevention checklist
- Full benefits check (not just eligibility) for any elective service, new drug, or DME order.
- Cross-benefit awareness — drugs billed under the medical benefit may be covered under the pharmacy benefit and vice versa.
- Pre-visit financial counseling for known-non-covered services with a financial-responsibility form.
Appeal strategy — step by step
Most CARC 204 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.
- 1Verify whether the service is covered under a different benefit (pharmacy vs. medical, behavioral carve-out) and redirect if so.
- 2If the plan document actually covers the service and the payer applied an incorrect exclusion, appeal with the specific plan-document section.
- 3For Medicare non-covered services, verify whether an ABN was executed — if yes, bill the patient; if no, write off.
Sample appeal-letter language for CARC 204
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 204 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 204?
Out of 306 seeded CARCs, ranked by combined US monthly search volume for "CARC 204", "CO-204 denial", and "denial code 204".
Platform frequency ranks publish once the anonymized denial-rate pipeline reaches the publication threshold (strategy §12 Phase 2).
How QuickRCM prevents CARC 204
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.
CAQH CORE code combinations for CARC 204
Under the CAQH CORE Payment and Remittance Uniform Use rule, health plans may pair CARC 204 only with the remark codes and group codes below for the defined business scenario 3 (Billed service not covered by the health plan). A combination outside this list on an 835 is itself a payer compliance issue worth raising.
| RARC | Remark description | Group code | Scenario |
|---|---|---|---|
| (no RARC) | CARC used without a remark code | CO, PI or PR | 3 |
| N10 | Adjustment based on the findings of a review organization/professional consult/manual adjudication/medical advisor/dental advisor/peer review. | CO, PI or PR | 3 |
| N12 | Policy provides coverage supplemental to Medicare. As the member does not appear to be enrolled in the applicable part of Medicare, the member is responsible for payment of the portion of the charge that would have been covered by Medicare. | CO, PI or PR | 3 |
| N129 | Not eligible due to the patient's age. | CO, PI or PR | 3 |
| N130 | Consult plan benefit documents/guidelines for information about restrictions for this service. | CO, PI or PR | 3 |
| N157 | Transportation to/from this destination is not covered. | CO, PI or PR | 3 |
| N158 | Transportation in a vehicle other than an ambulance is not covered. | CO, PI or PR | 3 |
| N171 | Payment for repair or replacement is not covered or has exceeded the purchase price. | CO, PI or PR | 3 |
| N180 | This item or service does not meet the criteria for the category under which it was billed. | CO, PI or PR | 3 |
| N357 | Time frame requirements between this service/procedure/supply and a related service/procedure/supply have not been met. | CO, PI or PR | 3 |
| N383 | Not covered when deemed cosmetic. | CO, PI or PR | 3 |
| N386 | This decision was based on a National Coverage Determination (NCD). An NCD provides a coverage determination as to whether a particular item or service is covered. A copy of this policy is available at www.cms.gov/mcd/search.asp. If you do not have web access, you may contact the contractor to request a copy of the NCD. | CO, PI or PR | 3 |
| N426 | No coverage when self-administered. | CO, PI or PR | 3 |
| N428 | Not covered when performed in this place of service. | CO, PI or PR | 3 |
| N429 | Not covered when considered routine. | CO, PI or PR | 3 |
| N441 | This missed/cancelled appointment is not covered. | CO, PI or PR | 3 |
| N448 | This drug/service/supply is not included in the fee schedule or contracted/legislated fee arrangement. | CO, PI or PR | 3 |
| N567 | Not covered when considered preventative. | CO, PI or PR | 3 |
| N569 | Not covered when performed for the reported diagnosis. | CO, PI or PR | 3 |
| N651 | No Personal Injury Protection/Medical Payments Coverage on the policy at the time of the loss. | CO, PI or PR | 3 |
| N658 | The billed service(s) are not considered medical expenses. | CO, PI or PR | 3 |
| N666 | Only one evaluation and management code at this service level is covered during the course of care. | CO, PI or PR | 3 |
| N751 | Adjusted because the patient is covered under a Medicare Part D plan. | CO, PI or PR | 3 |
| N789 | Clinical Trial is not a covered benefit. | CO, PI or PR | 3 |
| N794 | Payment adjusted based on type of technology used. | CO, PI or PR | 3 |
Frequently asked questions — CARC 204
What does CARC 204 mean?
CARC 204 is an X12 Claim Adjustment Reason Code. The official definition is: "This service/equipment/drug is not covered under the patient's current benefit plan." In plain English, the payer is telling you cARC 204 is a benefit-plan exclusion denial — the specific service, equipment, or drug is not in the patient's plan benefits. This is similar to CARC 96 but more often applied to pharmacy, DME, and tier-specific commercial benefits. Usually not appealable unless there is an error in how the plan was applied; the remedy is to move the balance to the patient after ABN/financial-responsibility, or to identify whether a different benefit category (e.g., pharmacy vs. medical benefit) applies.
How do I resolve a CARC 204 (CO-204) denial?
Start with the most common root cause: Service is a plan-document exclusion. First step: Verify whether the service is covered under a different benefit (pharmacy vs. medical, behavioral carve-out) and redirect if so. See the full remediation and appeal checklist on this page before filing a formal appeal.
Is CARC 204 patient responsibility?
No — CARC 204 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 204 look like on an EOB or 835 remittance?
On the 835 ERA, CARC 204 appears in Loop 2110 CAS segment as "CAS*CO*204*{amount}". On a paper EOB the same code prints in the Adjustment/Denial Reason column with the X12 description: "This service/equipment/drug is not covered under the patient's current benefit plan." — usually paired with one or more RARC remark codes in the same remittance line for additional context.
Which RARC is paired with CARC 204?
CARC 204 is commonly observed with RARC N115, N130, N362. The RARC narrows the reason — for example, pointing at a missing modifier, an LCD citation, or a specific policy. Fix the underlying CARC first; the RARC usually clears with the corrected claim.
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.