Skip to main content

CO-270 Denial Code: Medical Plan Denied, Bill Dental Plan

CO-270 means the medical plan received the claim but benefits aren't available under it, and you should submit the services to the patient's dental plan. The medical plan didn't forward the claim; you need to send it to the dental carrier yourself.

Quick facts

Code
CO-270 (CARC 270)
Status
Active In use since July 1, 2015; last modified November 1, 2017.
Code set
Claim Adjustment Reason Codes (CARC)
Group codes
  • CO (Contractual Obligation): The usual group. The provider should bill the dental plan instead; the patient isn't billed on the medical denial.
  • PR (Patient Responsibility): Sometimes used when the patient has no dental coverage and the medical plan assigns responsibility to the patient. Confirm dental coverage first.
Official description
Claim received by the medical plan, but benefits not available under this plan. Submit these services to the patient's dental plan for further consideration.
X12 Claim Adjustment Reason Codes, retrieved September 25, 2026
Last verified
against the official X12 list.

What CO-270 means

CARC 270 says the claim was received by the medical plan, but benefits aren’t available under this plan; submit these services to the patient’s dental plan. The medical payer looked at the service and decided it’s dental in nature. It isn’t paying, and it isn’t forwarding the claim either. You need to bill the dental carrier.

X12 notes that when the medical plan does forward the claim to the dental plan, payers should use CARC 291 instead. So CO-270 means the next step is yours.

Example: an oral surgeon bills an extraction to the patient’s medical plan. The medical plan considers routine extractions a dental benefit and returns CO-270. The practice rebills on a dental claim with the appropriate CDT code to the patient’s dental carrier.

Common causes

  • Dental services billed to a medical plan, such as extractions, restorations, or periodontal treatment.
  • Oral surgery where the medical plan covers only specific procedures or conditions.
  • Services by a dental provider that the medical plan treats as dental regardless of the code.
  • Accident-related dental care that wasn’t documented as accident-related.
  • Plans with separate dental carve-outs administered by another company.

How to fix it

  1. Confirm the patient’s dental coverage and the dental carrier’s information.
  2. Rebill to the dental plan in its required format with CDT codes, if applicable.
  3. If the service is medical, such as treatment of an accidental injury, a tumor, or infection, or a service required before a medical treatment, appeal to the medical plan with documentation and its policy.
  4. Coordinate benefits if both plans may cover part of the service, following each plan’s rules.
  5. Bill the patient only after dental and medical options are exhausted.

How to prevent it

  • Collect both medical and dental insurance for patients of oral surgery and dental practices.
  • Know which services each medical plan covers as medical versus dental.
  • Document medical necessity and accident details when billing dental-related services to medical plans.
  • Route claims correctly the first time. A Claims Validator check can flag dental-type services addressed to a medical payer.

Specialty notes

Oral and maxillofacial surgeons, hospital dental clinics, and dental practices doing cross-coding to medical plans see CO-270 most. Cross-coding rules differ by payer, so maintain a payer-specific list of services that go medical first.

Remark codes that may appear with CO-270

  • N130 (Consult plan benefit documents/guidelines for information about restrictions for this service.): Directs you to the medical plan's documents that exclude dental services.
  • CO-291 (Claim received by the medical plan, but benefits not available under this plan.): Same situation, but the medical plan forwarded the claim to the dental plan for you.
  • CO-254 (Claim received by the dental plan, but benefits not available under this plan.): The reverse: the dental plan says to bill the medical plan.
  • CO-289 (Services considered under the dental and medical plans, benefits not available.): Considered under both dental and medical plans, and benefits aren't available under either.
  • CO-109 (Claim/service not covered by this payer/contractor.): Not covered by this payer; send the claim to the correct payer.

CO-270 FAQ

What's the difference between CO-270 and CO-291?

With CO-270, you must submit the services to the dental plan yourself. With CO-291, the medical plan has already forwarded the claim to the dental plan, so you wait for the dental plan's response instead of rebilling.

Do I need a dental claim form?

Usually yes. Dental plans typically require the dental claim format (ADA form or 837D) with CDT codes. Check whether a CDT code applies to the service and whether the provider is enrolled with the dental plan.

When might the medical plan cover a dental-related service?

Some medical plans cover services related to accidental injury to teeth, certain oral surgery, or dental services needed for another medical treatment. If the service falls under one of those, appeal with documentation and the plan's policy.

What if the patient has no dental plan?

Confirm that with the patient. If there's no dental coverage and the medical plan's denial stands, bill the patient according to your financial policy.