Official X12 description
“Service not payable per managed care contract.”
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 256 actually means
CARC 256 denies the service because the provider's managed-care contract does not include it — typically capitated services, carve-outs, or non-contracted procedures. Check the contract matrix to confirm the service is indeed outside scope, then bill the correct payer (often a carved-out vendor) or shift to patient responsibility.
Common root causes
- Service carved out of the capitation arrangement (e.g., behavioral health, dental, vision routed to a different vendor).
- Contract does not include the specific CPT/HCPCS billed.
Prevention checklist
- Contract-matrix lookup at scheduling for carve-outs (behavioral, dental, vision, pharmacy benefit manager).
- Credentialing and contract loading checks for newly added services.
Appeal strategy — step by step
Most CARC 256 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.
- 1Rebill the carved-out vendor where applicable; a contract-scope denial from the primary plan cannot be appealed into coverage.
- 2If the service should be contracted but isn't, open a contracting ticket; this is a contract-management issue, not a denial.
Sample appeal-letter language for CARC 256
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 256 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 256?
Out of 306 seeded CARCs, ranked by combined US monthly search volume for "CARC 256", "CO-256 denial", and "denial code 256".
Platform frequency ranks publish once the anonymized denial-rate pipeline reaches the publication threshold (strategy §12 Phase 2).
How QuickRCM prevents CARC 256
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 256
Under the CAQH CORE Payment and Remittance Uniform Use rule, health plans may pair CARC 256 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 |
| M14 | No separate payment for an injection administered during an office visit, and no payment for a full office visit if the patient only received an injection. | CO, PI or PR | 3 |
| M37 | Not covered when the patient is under age 35. | CO, PI or PR | 3 |
| M61 | We cannot pay for this as the approval period for the FDA clinical trial has expired. | CO, PI or PR | 3 |
| M81 | You are required to code to the highest level of specificity. | CO, PI or PR | 3 |
| M82 | Service is not covered when patient is under age 50. | CO, PI or PR | 3 |
| M89 | Not covered more than once under age 40. | CO, PI or PR | 3 |
| M90 | Not covered more than once in a 12 month period. | CO, PI or PR | 3 |
| M96 | The technical component of a service furnished to an inpatient may only be billed by that inpatient facility. You must contact the inpatient facility for technical component reimbursement. If not already billed, you should bill us for the professional component only. | CO, PI or PR | 3 |
| M97 | Not paid to practitioner when provided to patient in this place of service. Payment included in the reimbursement issued the facility. | CO, PI or PR | 3 |
| M139 | Denied services exceed the coverage limit for the demonstration. | CO, PI or PR | 3 |
| MA16 | The patient is covered by the Black Lung Program. Send this claim to the Department of Labor, Federal Black Lung Program, P.O. Box 828, Lanham-Seabrook MD 20703. | CO, PI or PR | 3 |
| N52 | Patient not enrolled in the billing provider's managed care plan on the date of service. | CO, PI or PR | 3 |
| N95 | This provider type/provider specialty may not bill this service. | CO, PI or PR | 3 |
| N103 | Records indicate this patient was a prisoner or in custody of a Federal, State, or local authority when the service was rendered. This payer does not cover items and services furnished to an individual while he or she is in custody under a penal statute or rule, unless under State or local law, the individual is personally liable for the cost of his or her health care while in custody and the State or local government pursues the collection of such debt in the same way and with the same vigor as the collection of its other debts. The provider can collect from the Federal/State/ Local Authority as appropriate. | CO, PI or PR | 3 |
| N117 | This service is paid only once in a patient’s lifetime. | CO, PI or PR | 3 |
| N118 | This service is not paid if billed more than once every 28 days. | CO, PI or PR | 3 |
| N130 | Consult plan benefit documents/guidelines for information about restrictions for this service. | CO, PI or PR | 3 |
| N246 | State regulated patient payment limitations apply to this service. | CO, PI or PR | 3 |
| N428 | Not covered when performed in this place of service. | 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 |
| N623 | Not covered when deemed unscientific/unproven/outmoded/experimental/excessive/inappropriate. | CO, PI or PR | 3 |
| N734 | The patient is eligible for these medical services only when unable to work or perform normal activities due to an illness or injury. | CO, PI or PR | 3 |
| N853 | The number of modalities performed per session exceeds our acceptable maximum. | CO, PI or PR | 3 |
| N906 | Service is not covered when a patient is under age 45. | CO, PI or PR | 3 |
Frequently asked questions — CARC 256
What does CARC 256 mean?
CARC 256 is an X12 Claim Adjustment Reason Code. The official definition is: "Service not payable per managed care contract." In plain English, the payer is telling you cARC 256 denies the service because the provider's managed-care contract does not include it — typically capitated services, carve-outs, or non-contracted procedures. Check the contract matrix to confirm the service is indeed outside scope, then bill the correct payer (often a carved-out vendor) or shift to patient responsibility.
How do I resolve a CARC 256 (CO-256) denial?
Start with the most common root cause: Service carved out of the capitation arrangement (e.g., behavioral health, dental, vision routed to a different vendor). First step: Rebill the carved-out vendor where applicable; a contract-scope denial from the primary plan cannot be appealed into coverage. See the full remediation and appeal checklist on this page before filing a formal appeal.
Is CARC 256 patient responsibility?
No — CARC 256 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 256 look like on an EOB or 835 remittance?
On the 835 ERA, CARC 256 appears in Loop 2110 CAS segment as "CAS*CO*256*{amount}". On a paper EOB the same code prints in the Adjustment/Denial Reason column with the X12 description: "Service not payable per managed care contract." — usually paired with one or more RARC remark codes in the same remittance line for additional context.
Which RARC is paired with CARC 256?
CARC 256 is commonly observed with RARC N216. 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.