CO-109 Denial Code
What it means
You sent the claim to the wrong insurer (or wrong plan). This payer isn't responsible for it.
Why it happens
Outdated insurance on file, wrong plan ID, or the service belongs to a different carrier/network.
What to do
Confirm the correct payer and plan, update the info with the provider, and have the claim resubmitted to the right insurer.
Can you appeal it?
Resubmit to the correct payer rather than appeal.
Official description
Claim/service not covered by this payer/contractor; send to the correct payer.
Decode your full denial letter
Paste or upload your letter and get the deadline, escalation ladder, and a ready-to-send appeal letter - free during early access.
Decode your full denial letter