CO-254 comes from a dental plan. It says the service is not a dental benefit and the claim belongs with the patient’s medical insurance. The dental plan did not send it on for you. So the office must file a new claim with the medical plan, on the medical claim form, with medical codes. (Primary source: X12 Claim Adjustment Reason Codes)
In brief: CARC 254 reads “Claim received by the dental plan, but benefits not available under this plan. Submit these services to the patient’s medical plan for further consideration.” Get the medical plan details, rebuild the claim on the CMS-1500 with ICD-10 and CPT or HCPCS codes, and attach the dental EOB if the medical plan asks.
Part of our denial codes library. Written by Manikandan J, CPC, CRCR, who has worked cross-coded dental and medical claims for oral surgery and sleep apnea offices. Published 24 October 2026. Last updated: 24 October 2026. Code wording quoted word for word from X12. Read about the author and our editorial policy, or contact us to report an error.
The X12 definition
| Field | Value |
|---|---|
| Code | 254 |
| Description | “Claim received by the dental plan, but benefits not available under this plan. Submit these services to the patient’s medical plan for further consideration.” |
| Start | 06/02/2013 |
| X12 note | Use CARC 290 when the claim was forwarded |
Source: X12 Claim Adjustment Reason Codes, checked 24 October 2026.
Key terms: A CARC is a Claim Adjustment Reason Code from the X12 list, and it says why a line was paid differently than billed. A RARC is a Remittance Advice Remark Code that adds detail to the CARC. The group code is the two-letter prefix on the adjustment; CO means contractual obligation: the provider owns the balance and it cannot be billed to the patient.
Methodology: the code wording above is copied from the X12 list, and each fix step below links to the payer or CMS page it comes from.
CARC 290 is the twin code. It reads “Claim received by the dental plan, but benefits not available under this plan. Claim has been forwarded to the patient’s medical plan for further consideration.” With 290 you wait for the medical plan. With 254 you file it yourself.
Example scenario (fictional names), part 1
CO-254 Denial Example: What Happened
Dana Whitfield runs billing for Harbor Dental Sleep, a fictional dental office. The dentist made a custom oral appliance for a patient with obstructive sleep apnea and billed it to the patient’s dental plan.
The dental EOB showed CAS*CO*254. Nothing was forwarded.
Where does the claim go now, and what has to change? Keep reading, or jump to how the CO-254 denial was resolved.
Services that often belong to the medical plan
- Sleep apnea appliances. Treatment of a medical diagnosis such as obstructive sleep apnea.
- Trauma. For example, a jaw fracture or teeth broken in a car accident or fall.
- Oral pathology. Biopsies and lesion removal.
- TMJ treatment. Many dental plans exclude it.
- Care tied to a medical condition. Some plans cover dental work before radiation or transplant under medical benefits.
Coverage varies by plan. Check the dental plan’s exclusions and the medical plan’s policy before you bill. HealthCare.gov’s dental coverage page explains how the two kinds of coverage differ.
Moving a CO-254 claim to the medical plan
- Collect the medical plan details. Get the member ID, group number and claims address from the patient’s medical card.
- Check medical plan rules. Confirm the office is in network or can bill out of network, and whether prior authorization is needed.
- Recode the service. Dental CDT codes from the ADA do not go on a medical claim. Use CPT or HCPCS for the service and ICD-10-CM for the diagnosis.
- Use the medical claim form. File on the CMS-1500, following the NUCC instructions, or the 837P.
- Support it. Include the sleep study result, physician order or other records the medical plan requires, and the dental EOB if asked.
Example scenario (fictional names), part 2
How the CO-254 Denial Was Resolved
Dana collected the patient’s medical plan card and checked its oral appliance policy. Prior authorization was required.
Fix: She got the authorization and billed the medical plan on a CMS-1500. She used HCPCS E0486 for the appliance and G47.33 for obstructive sleep apnea. The sleep study and physician order went with it.
Outcome: The medical plan paid under the patient’s DME benefit. The office now checks medical coverage before fitting any sleep appliance.
Names and details are illustrative; no real patient data.
Dental-to-medical codes side by side
| Code | Meaning | Who acts |
|---|---|---|
| CO-254 | Not a dental benefit, not forwarded | Office bills the medical plan |
| CARC 290 | Not a dental benefit, forwarded | Wait for the medical plan |
| CO-109 | Wrong payer or contractor | Send to the correct payer |
| CO-22 | Another payer may be primary | Coordination of benefits |
FAQ
What does CO-254 mean?
The dental plan says the service is not a dental benefit and the claim should go to the patient’s medical plan.
Can I send the same dental claim to the medical plan?
No. Medical plans need a medical claim with ICD-10-CM diagnosis codes and CPT or HCPCS service codes.
How is CO-254 different from CARC 290?
With 290 the dental plan forwarded the claim. With 254 it did not, so you must file it.
Can the patient be billed after CO-254?
Not yet. Bill the medical plan first. Patient responsibility depends on what the medical plan decides.
Does a dental office need medical plan enrollment?
Often yes, especially for in-network billing. Check with the medical plan before treatment.
Sources
How we checked: the code wording on this page was matched word for word with the X12 CARC list on 24 October 2026.
- X12, Claim Adjustment Reason Codes (CARC 254 and 290). Accessed 24 Oct 2026.
- HealthCare.gov, Dental coverage. Accessed 24 Oct 2026.
- ADA, CDT code set. Accessed 24 Oct 2026.
- NUCC, 1500 Claim Form instructions. Accessed 24 Oct 2026.
Last updated: 24 October 2026 ยท Educational content; not legal advice.
Related denial codes
- CO-270: Bill the Patient's Dental Plan
- PR-204: Not Covered Under the Patient's Current Benefit Plan
- CO-256: Service Not Payable Per Contract
- OA-257: Claim Pended in the Grace Period
- CO-258: Patient in Custody or Incarcerated
- CO-269: Anesthesia Not Covered for the Service
- CO-239: Rebill Separate Claims by Coverage Period
- PR-238: Coverage Ended Partway Through the Claim