CO-243 Denial Code Explained

CO-243 is a medical billing denial code that indicates the service was not authorized by the network or primary care provider when authorization was required. This denial commonly occurs when referral or authorization requirements are not met before treatment is provided.

What Does CO-243 Mean?

The CO-243 denial code means the payer requires authorization, referral, or approval before the service can be covered.

This denial is often related to managed care plans, network requirements, and referral policies.

Common Reasons for CO-243

• Missing prior authorization

• Missing referral from primary care provider

• Authorization obtained after services were rendered

• Service performed outside network requirements

• Incorrect authorization information

• Authorization does not cover the billed service

How To Fix CO-243

Review the patient's insurance requirements and verify whether prior authorization or a referral was required before treatment. Confirm that authorization details match the service billed on the claim.

If the denial was issued incorrectly, submit supporting documentation and authorization records to the payer for review.

If the denied service involved a specific procedure or office visit code, review the coding requirements before resubmission. Additional coding resources can be found on CPTCodeGuide.com.

Frequently Asked Questions

What does CO-243 mean?

CO-243 means the service was not authorized by the network or primary care provider when authorization was required.

Can CO-243 be appealed?

Yes. Providers may appeal if authorization was obtained or if supporting documentation demonstrates the service should be covered.

Is CO-243 related to prior authorization?

Yes. Missing or invalid prior authorization is one of the most common causes of CO-243 denials.

Can referrals cause CO-243 denials?

Yes. Some health plans require a referral from the patient's primary care provider before specialty services are covered.

Can I bill the patient for a CO-243 denial?

This depends on payer rules, provider contracts, and whether the patient was informed of potential financial responsibility.

Related Denial Codes

You may also encounter:

• CO-16 — Missing or incomplete claim information

• CO-197 — Authorization absent

• CO-97 — Bundled procedure denial

• CO-197 — Authorization absent

Quick Summary

CO-243 indicates the service was not properly authorized before treatment was provided. Most denials are caused by missing referrals, missing prior authorization, or network requirements.