CARC 100: Payment made to patient/insured/responsible party
The insurance payment was sent directly to you instead of to the provider.
What this means for your claim
When a provider doesn't have an assignment of benefits agreement with your insurer, payment can go directly to the patient. You're then responsible for paying the provider.
What to do next
- 1
Check if you received a check from your insurer and forward it to the provider.
- 2
Inform the provider so they don't send the account to collections while waiting for payment.
- 3
For future services, provide the provider's current billing address to the insurer to enable direct payment.
How to handle a non-covered or denied service
Non-covered codes mean the insurer is declining to pay — either because the plan excludes the service, because medical necessity wasn't established, or because a requirement like prior authorization or timely filing wasn't met. These are the adjustments most worth contesting, because a denial is not the final word: a large share of denials are overturned on appeal when the patient or provider supplies the right documentation.
Find the exact reason for the denial in writing
"Not covered" is a category, not an explanation. Call your insurer and ask specifically why: Is the service excluded from your plan? Was it deemed not medically necessary? Was prior authorization missing? Was the claim filed late by the provider? The precise reason determines who fixes it and how.
Decide whether it's the provider's error or a true plan exclusion
If the problem is a missing prior authorization, a coding error, or late filing, that is usually the provider's responsibility — and in many states they cannot bill you for their own administrative mistakes. If the service is genuinely excluded from your plan, your path is an appeal or financial assistance, not a billing correction.
Gather support for medical necessity before you appeal
When a denial is based on medical necessity, ask your treating physician for a letter of medical necessity and the clinical notes that justify the service. Insurers overturn a meaningful portion of these denials once the supporting documentation is in front of a reviewer.
Your appeal rights for CARC 100
You have a federally protected right to appeal a denial. Request the insurer's full reason and your plan's appeal deadline in writing, then file an internal appeal with your supporting documents. If the internal appeal is denied, you can request an independent external review — a reviewer with no financial stake in the outcome. If the service was an emergency or from an out-of-network provider at an in-network facility, the federal No Surprises Act may also protect you from balance billing.
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