Free Tool — No Account Required

Free Denial Resolution Tool

Paste your denial code (CARC, RARC, or combo) and get a step-by-step resolution plan in seconds. Covers all 300+ CARC codes, 800+ RARC codes, and 1,700+ denial code combinations with payer-specific appeal guidance.

Where to find your codes on the EOB

CARC — “Reason Code”, “Adjustment Reason”, or “CARC” on the EOB line itemRARC — “Remark Code” or “RARC” next to the CARC

Claim Details (optional — improves accuracy)

Denied Procedure Lines (enter only denied lines — not paid lines)

Line 1

What's the current claim status?

How It Works

1

Enter your denial code

Type a CARC code (e.g., CO-45), RARC code (e.g., MA04), or a combination like CO-45 + N362.

2

Get a plain-English explanation

Instantly see why this denial happened, who is financially responsible, and whether it's worth appealing.

3

Follow the resolution plan

Step-by-step action plan with required documents, payer-specific notes, and a free appeal letter generator.

Most Searched Denial Codes

CO-45Charge exceeds fee scheduleResolution guide →CO-97Payment bundled with another serviceResolution guide →CARC 27Expenses after coverage terminatedResolution guide →CO-50Not medically necessary per payer policyResolution guide →CARC 253Sequestration reductionResolution guide →

Frequently Asked Questions

What is a CARC code?

A CARC (Claim Adjustment Reason Code) is a standardized code used in insurance remittance advice (EOBs and ERAs) to explain why a claim was adjusted or denied. CARC codes are published by the X12 organization and are used by all US health insurers. Common examples: CARC 16 (missing information), CARC 50 (not medically necessary), CARC 18 (duplicate claim).

What is a RARC code?

A RARC (Remittance Advice Remark Code) provides supplemental information to a CARC code. While a CARC identifies the reason for the adjustment, a RARC adds specific detail. For example, CARC 50 (not medically necessary) paired with RARC N362 means the documentation to support medical necessity is missing specifically. RARCs are optional but increase the specificity of the resolution plan.

How many denial lines can I enter?

You can enter up to 10 denied lines per claim submission. Lines with the same CARC code are automatically grouped into a single resolution plan, matching how billing teams actually work (one appeal per denial reason per claim). You only need to enter denied lines — paid lines are not relevant.

Is this tool free?

Yes — the denial resolution plan (triage, action steps, required documents, payer intelligence) is completely free with no account required. Generating an AI-written appeal letter requires a free Arceum account and is limited to 3 per month.

Does this contain patient health information (PHI)?

No. The Denial Resolver only collects CARC codes, RARC codes, procedure codes, payer name, and days since date of service. No patient names, member IDs, dates of birth, or any other protected health information (PHI) are entered or stored. The generated appeal letters use [BRACKETED PLACEHOLDERS] for all PHI fields that you fill in locally.