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Health Agentby Bonis Systems

Health Agent · Denial codes in plain English

That code on your denial means something. Find out what.

Every denied claim carries a code like CO-50 or PR-1. Hidden inside it is the one fact insurers rarely spell out: whether you can even be billed for the amount. Enter the code and read it in plain English — what it means, who owes it, and the typical fix.

Runs in your browser Nothing leaves your device No account Standard CARC denial codes

Decoder

Enter the denial code

It's on your explanation of benefits, usually next to the denied line. Include the letters if you have them (CO, PR, OA).
Try one:

The one thing to know

The two letters in front of the number tell you who can be billed. CO is the provider's contractual write-off — you generally should not be balance-billed for it. PR is the part assigned to you. People pay CO amounts they never owed all the time.

Group codes

What the letters mean

    How it works

    Read on your machine, not on a server

    The decode runs in the page you already loaded. The code you enter — and everything on your explanation of benefits — stays on your device; there is no upload and no account. The meanings are the standard industry CARC (Claim Adjustment Reason Code) definitions, the same ones every payer uses. See the proof →

    This page tells you what a code means and the typical fix. It does not predict whether an appeal will succeed, and it is not legal or medical advice. When a denial is worth appealing, the next move is always the same: check your filing deadline first.

    Questions

    Common questions

    Does the code I enter get sent anywhere?

    No. The decode is computed by code already running in your browser. There is no server endpoint behind this page — what you type never travels over the network and is not stored.

    It says "CO" — does that mean I don't owe it?

    CO stands for Contractual Obligation: the provider agreed in their contract with the plan to write that amount off, so you generally should not be balance-billed for it. If you're being billed for a CO amount, that's worth questioning. It is still wise to confirm with the provider and your plan.

    Why doesn't it know my code?

    This decoder carries the most common caregiver-facing codes in plain English. There are hundreds of rarer ones; if yours isn't here, the group letter still tells you who can bill you, and your plan's denial-code list or explanation of benefits will have the full text.

    Is this legal advice?

    No. This is a plain-English decoder and a pointer to the typical fix — not legal or medical advice, and it does not file anything for you. Confirm specifics with your plan or a licensed advisor. Health Agent is not affiliated with or endorsed by Medicare.