CO-209: Provider Cannot Collect from Patient per Regulatory Agreement

What Does CO-209 Mean?

With CO (Contractual Obligation), the adjustment is treated as a contractual matter. The provider cannot collect from the patient. If the amount should be covered by another payer, submit to that payer.

CARC 209 is a critical compliance code that signals the provider cannot bill the patient for the adjusted amount. Federal or state regulations, or contractual agreements, prohibit collecting this balance from the patient. The most common scenario is a Qualified Medicare Beneficiary (QMB) — federal law prohibits providers from collecting Medicare deductibles, coinsurance, and copayments from QMB patients.

This code also applies under the No Surprises Act, state balance billing laws, and certain contractual arrangements. If a secondary payer exists, the provider may submit the claim to that payer. Otherwise, the amount must be adjusted off the account. Billing the patient for this amount violates federal or state law and can result in penalties.

How to Resolve

1. Do not bill the patient The patient is protected from this charge.
2. Submit to other payers if applicable Check for secondary coverage and submit accordingly.
3. Adjust the balance Write off the amount if no other payer covers it.

How to Prevent CO-209

• Verify patient protections before collecting any payments
• Maintain awareness of contractual collection restrictions

Also Filed As

The same CARC 209 may appear with different Group Codes:

Related Denial Codes