CO-199CO group · Coding

CO-199 denial code: revenue code and procedure code do not match

CO-199 lives on institutional claims, where every line carries two codes that have to agree with each other.

CO-199 fires when the revenue code and the procedure code on an institutional claim line do not correspond. Each describes the service from a different angle, and payers maintain crosswalks defining which pairings are acceptable.

What CO-199 means

Revenue codes describe the department or cost centre; procedure codes describe what was done. A radiology procedure under a laboratory revenue code fails not because either is wrong alone but because the pairing is incoherent. Chargemaster maintenance is where these originate: a chargemaster line built with the wrong revenue code produces the same denial on every claim that uses it until the chargemaster is corrected.

Why CO-199 fires

  • The chargemaster line carries the wrong revenue code for the procedure.
  • A procedure moved departments and the revenue code was not updated.
  • A payer-specific crosswalk differs from the national convention.
  • A supply or drug was billed under a service revenue code.

Is CO-199 worth appealing?

Sometimes worth appealing

Correct the pairing, and correct it in the chargemaster rather than on the claim. A single wrong chargemaster line denies every claim built from it.

How to resolve or appeal CO-199

  1. 1

    Identify the failing pair

    The remark code usually names the line; confirm which of the two codes is wrong.

  2. 2

    Fix the chargemaster

    Correcting the claim alone leaves the source producing the same denial tomorrow.

CO-199 — frequently asked

Is this a professional-claim problem?
No. Revenue codes appear on institutional claims, so this is a facility billing issue rather than a physician one.
Do payers use the same crosswalk?
Mostly, but not entirely. Payer-specific pairings exist and are worth confirming when a pairing that works elsewhere fails at one payer.

Related guides

CO-16 · AdministrativeCO-236 · CodingCO-4 · Coding

Sources

Reason-code meanings are paraphrased from the X12 Claim Adjustment Reason Code list for plain-language reference; they are not reproduced verbatim. This is general information, not legal, coding, or medical advice — always confirm against the payer's remittance and policy.

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