What does CARC 204 mean?

CARC 204 means the service, equipment, or drug is not covered under the patient's current benefit plan. The denial always ties back to a specific plan document such as the Summary of Benefits or Evidence of Coverage.

How is CARC 204 different from CARC 96?

CARC 96 is the general non-covered charge code and can reflect statutory exclusions, National Coverage Determinations, or plan exclusions. CARC 204 is specifically plan-document driven: the payer read the member's specific plan and concluded the service is excluded. CARC 204 typically stands alone without a paired RARC, and it always points you at a plan document.

Can I appeal a CARC 204 denial?

Yes, when the plan document actually covers the service, when the payer misclassified the CPT code, when the payer adjudicated against the wrong plan year, or when coverage criteria are met and were overlooked. If the plan document clearly and specifically excludes the service, the appeal will fail.

Can I bill the patient for a CARC 204 denial?

Only if the group code is PR (Patient Responsibility) and your payer contract permits billing for excluded services. If the group code is CO (Contractual Obligation), you are contractually barred from billing the patient and must write off the balance or appeal.

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CARC Code Reference

CARC 204: Not covered under the patient's current benefit plan. What it means, and how to appeal it.

CARC 204 tells you the payer read the patient's specific plan and concluded the service is not a covered benefit. That is different from CARC 96, which can cover statutory exclusions, National Coverage Determinations, or plan-rule denials. CARC 204 always points you at a plan document. The document is where the answer lives, and the difference between a legitimate write-off and a recoverable payer error usually comes down to whether anyone bothered to pull it.

By Mindy Corbett, CSPO, CPC, CPB, CPPM · 6 min read

CARC 204

CLAIM ADJUSTMENT REASON CODE

This service/equipment/drug is not covered under the patient's current benefit plan.

Medium Risk

What This Means

This service, equipment, or drug is not covered under the patient's current benefit plan.

Common drivers: Service is on the plan's explicit exclusion list; drug is non-formulary or lacks an active exception; or equipment is categorized as non-covered under plan benefit design.

Root Causes

Service is on the plan's explicit exclusion list; drug is non-formulary or lacks an active exception; or equipment is categorized as non-covered under plan benefit design.

Action Plan

Pull the plan's Evidence of Coverage and confirm the specific service, drug National Drug Code (NDC), or equipment type is explicitly excluded or absent from covered benefits.
Determine whether a formulary exception, coverage exception, or alternative covered code exists.
If no coverage applies, post the contractual adjustment and advise the patient.

Appeal Tips

For drug denials, submit the prescribing physician's letter of medical necessity and evidence of formulary alternative failure or contraindication for a formulary exception.
For service or equipment denials, cite plan benefit language if the exclusion was misapplied.

Prevention Strategy

During benefits verification, check the plan's exclusion list specifically for the service, drug NDC, or equipment type - do not rely solely on a general eligibility response.
For high-risk services, obtain a pre-service coverage determination before rendering.

✅ Verified 2026-06-16 · Source: ASC X12 · Rendered live from the EDI Code Intelligence Lab data set.

What CARC 204 Actually Means

Claim Adjustment Reason Code (CARC) 204 is the plan-specific non-covered denial. The payer is telling you that this service, equipment, or drug is not a covered benefit under the patient's current plan. CARC 204 always ties back to a specific plan document: the Summary of Benefits, the Evidence of Coverage, or the plan's benefit grid. That document is where the answer lives.

CARC 204 is not a general coverage denial. It is a statement that the payer read the patient's specific plan and concluded the service is excluded. That distinction matters, because it changes how you work it. With CARC 96 (the general non-covered code), the denial can reflect a statutory exclusion, an NCD, or a coverage-rule decision. With CARC 204, the denial is always plan-document driven, which means the plan document is always the answer.

Two Kinds of CARC 204

There are effectively two flavors of CARC 204 in the wild, and they require different responses:

The plan actually excludes the service. The Evidence of Coverage explicitly lists the service, drug, or equipment as an excluded benefit. The denial is correct. The balance is patient responsibility (with a PR group code) or a contractual write-off (with a CO group code) depending on your payer contract.
The payer misread the plan. The service is actually covered, but the payer applied the wrong benefit rule, misclassified the CPT/HCPCS code, or auto-adjudicated against a different plan's exclusion list. This is a payer error, and it is appealable.

The only way to tell the two apart is to pull the plan document. There is no shortcut. If your team is writing off CARC 204 denials without checking the plan document, you are almost certainly writing off recoverable revenue.

How to Read the Plan Document

Every plan has a covered-services list and an excluded-services list. For CARC 204:

Locate the exact CPT/HCPCS code or service category on the excluded list. If it is there, the denial is correct.
If the code is not on the excluded list, check the covered-services list. If it is there, the payer is wrong and the appeal ground is straightforward: the plan covers this service.
If the code is on neither list, check the medical necessity or plan-limitation sections. Some services are covered only under specific conditions (age, diagnosis, prior-service history). If those conditions are met, the appeal ground is that the service qualifies under the plan's coverage criteria.
Note the plan year. If you rendered the service in one plan year but the payer adjudicated against a different plan year, the exclusion may not apply. This is a common payer error at year-end and open-enrollment periods.

The Group Code Determines Who Pays

CARC 204 with different Claim Adjustment Group Codes (CAGCs) leads to different next steps:

PR (Patient Responsibility): The plan does not cover this service, and your payer contract permits patient billing for excluded services. Send the statement. Include an explanation of benefits and, if useful, an offer to help the patient appeal to their plan.
CO (Contractual Obligation): Your payer contract bars you from billing the patient for this exclusion. The balance is written off. Appeal only if you believe the payer misread the plan.
OA / PI (Other or Payer Initiated): These are less common on CARC 204 and usually signal a payer-side adjustment or a benefit-coordination issue.

The most damaging pattern on CARC 204 is a CO group code applied to a service the plan actually covers. That combination means the payer is denying a covered service and your contract is barring you from collecting from the patient. Every occurrence is lost revenue that appeals can recover.

How to Appeal CARC 204

Pull the plan document - the Summary of Benefits, the Evidence of Coverage, or the specific benefit grid that applies to the member's plan on the date of service.
Cite the coverage section. Quote the exact language that lists the service as covered, or the coverage criteria the service meets.
Attach documentation. Include the eligibility check, any prior authorization, and the clinical documentation that supports coverage under the plan's criteria.
Address the exclusion the payer applied. If the denial cited a specific exclusion category (durable medical equipment, cosmetic services, experimental treatments), explain in the appeal letter why that exclusion does not apply to this specific service.
Request written response with the plan document reference. A well-formed appeal forces the payer to cite the specific plan document section they are applying. That citation gives you the record you need for a second-level appeal or an external review.

When CARC 204 Is Genuinely Not Appealable

If the plan document clearly and specifically excludes the service (for example, a plan that explicitly excludes acupuncture and the claim is for acupuncture), the denial is correct and the appeal will fail. In these cases, the productive path is:

Bill the patient (if the group code is PR and the payer contract permits).
Educate the intake team so future patients on the same plan are informed of the non-coverage before the service.
Consider a benefit-verification workflow that flags known-excluded services during scheduling.

How to Prevent CARC 204 Denials

Move plan-benefit verification into intake for elective and high-cost services. Do not rely on an eligibility check that only confirms active status.
Build a plan-exclusions library for your top payers and their most-common plan variants. Patterns emerge fast, and once you know a plan excludes a service category, you can flag it at scheduling.
Track CARC 204 by payer + plan + CPT code. Recurring patterns tell you either a payer configuration problem to escalate or a plan design your patients should know about in advance.
When the plan document contradicts the denial, escalate at the payer level. One documented pattern of misapplied exclusions can trigger a plan-wide correction that resolves months of similar denials.

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Related Resources

CARC 204 pairs closely with the general non-covered denial pattern in the CARC 96 denial brief. Templated appeal language is available in the Non-Covered Service Appeal Template.