CO-204: Not covered under the patient plan

What CO-204 means

The plan excludes this service, or coverage was not active the way the claim assumed.

What it usually means in a chiropractic office

Some plans exclude chiropractic entirely, exclude specific services like therapies while covering CMT, or the patient changed plans and the office billed the old card.

How to work it

1. Re-verify eligibility as of the date of service.
2. If the plan changed, update the insurance and rebill the active plan.
3. If the patient holds secondary coverage, rebill against it.
4. If genuinely excluded, the balance is patient responsibility with the proper financial policy in place.

What this looks like in practice

A patient changes employers in January and hands over the new card in March. Claims for January and February went to the old plan and paid, then the old plan recouped them after learning of the termination, and the new plan denies the resubmissions as out of window services under a plan that excludes chiropractic entirely. What looked like one denial is actually a coverage story spanning three months.

How to stop it from happening again

• ✓Verify eligibility ahead of visits, not after denials
• ✓Recheck coverage every January and after any known job change
• ✓Record plan exclusions on the patient insurance profile the first time you learn them

General information for billing teams, not legal or payer specific advice. CARC definitions belong to X12; payer policies vary and control. Verify against the payer contract before acting on any individual claim.