Draft, not yet reviewed. Content on this page is a work in progress.
CO-97CO-97 denial: what it means and how to fix it
CO-97 means the payer considers this service already paid for as part of another service billed on the same claim (or a related claim) — essentially, it's bundled into a procedure that was already reimbursed, so it isn't paid separately.
Common causes
- Two codes billed together are considered bundled under the payer's or CMS's National Correct Coding Initiative (NCCI) edits
- A missing modifier (like 25 or 59) that would have unbundled the services wasn't included
- An add-on or component code was billed without its required primary/base code on the same claim
- The service is considered part of a global surgical or procedural package that was already billed
How to fix it
- Check the payer's or CMS NCCI edit tables to see if the two codes are bundled and whether a modifier is allowed to separate them
- If a modifier applies and is supported by documentation, add it and resubmit
- If the code is an add-on code, confirm the primary code was billed on the same claim
- If the bundling is correct and no modifier applies, this typically isn't appealable — verify your fee schedule reflects that this line won't be separately reimbursed
Template pack letters for CO-97
- Appeal supporting a modifier and separately payable service
General guidance only. Payer rules vary, so always check the payer's policy.
See the official X12 description