CO-97
Denial Code CO-97: Payment Included in Another Service
Bundled into another service already paid
What CO-97 officially means
The benefit for this service is included in the payment/allowance for another service/procedure that has already been adjudicated.
Source: X12 Claim Adjustment Reason Codes
What actually causes it
A procedure and an office visit billed on the same day without modifier 25
The payer treats the evaluation as part of deciding to do the procedure. Where a separately identifiable problem was addressed, modifier 25 applies, but the note has to show two distinct services rather than one visit described twice.
Two procedures that the payer bundles under its edits
National Correct Coding Initiative edits pair thousands of codes as mutually exclusive or as components of each other. When both are billed without a modifier, the lower valued one is denied.
A visit inside a surgical global period
A procedure with a 10 or 90 day global period includes routine follow-up. Care unrelated to the surgery needs modifier 24, and an unplanned return to theatre needs 78. Without one of those, the visit is bundled.
How to fix it
Start by finding out which service absorbed the one that was denied. The remittance advice names it, and until you know what it was you are guessing about whether the bundle is correct. Roughly half the CO-97 denials we see are simply right, and appealing those costs time that should go to the other half.
Work out whether the services were genuinely separate
Ask what a reviewer would see in the note. If a patient came in for a scheduled lesion excision and the visit consisted of consenting them and doing it, there is one service, and the payer is right. If the patient came in about their diabetes, and the lesion was noticed and removed during the same visit, there are two, and modifier 25 belongs on the E/M code.
The distinction has to be visible in the documentation written at the time. A note that describes one encounter cannot be turned into two by adding a modifier afterwards, and payers audit modifier 25 specifically because that is what practices do with it.
Check the edit before you argue with it
For procedure-to-procedure bundles, look up the code pair in the NCCI edits published by CMS. Each pair carries an indicator saying whether a modifier can override it at all. If the indicator is 0, no modifier will work and the appeal has nowhere to go. If it is 1, a modifier is permitted when the services really were distinct.
That lookup takes a minute and it decides whether there is a case. Practices that skip it end up filing appeals that were never winnable.
Use the specific modifier, not the general one
Modifier 59 is the blunt instrument, and Medicare has been steering practices away from it for years in favor of the X modifiers, which say what kind of separation you are claiming: a different encounter, a different practitioner, a different anatomical site, or a distinct non-overlapping service. Use the specific one where it applies. It survives review better because it states an argument rather than asserting a conclusion.
Global periods are usually not appealable
If the denial is for a post-operative visit inside a global period, check the surgery date and the global length before doing anything else. Routine follow-up is included, and no modifier changes that. What is appealable is care for an unrelated problem, which takes modifier 24, or a return to theatre for a complication, which takes 78.
Practices that see a lot of these usually have a tracking problem rather than a coding problem. If nobody knows a patient is inside a global period at the point of scheduling, the wrong code goes out every time.
Fix the pattern, not the claim
One CO-97 is an administrative task. The same CO-97 every month is a template or a workflow producing it, and correcting the claim does nothing about next month's. Orthopedic practices tend to find it in global period tracking; dermatology usually finds it in same-day procedure and visit habits.
If you are seeing these in volume, our coding review looks at the pattern across your whole panel rather than claim by claim.
Is CO-97 worth appealing?
Yes, appealable
Appealable when the two services were genuinely separate and the documentation written at the time shows it. Check the NCCI modifier indicator first: where it is 0, no modifier can override the edit and there is no appeal to make. Post-operative visits inside a global period are not appealable unless the care was unrelated to the surgery or required a return to theatre.
Common questions
Can I just add modifier 59 and resubmit?
Only if the services were genuinely distinct and the note already showed it. Adding modifier 59 to get a claim paid, without documentation supporting the separation, is the pattern payers audit for. Check the NCCI modifier indicator first, because some pairs cannot be overridden at all.
Why do we get CO-97 on every post-op visit?
Because the surgery has a global period, usually 10 or 90 days, and routine follow-up was included in the surgical payment. That is the rule working as intended rather than an error. Only unrelated care or a return to theatre is separately billable.
How do we know which service it was bundled into?
The remittance advice identifies it. Work from that rather than guessing, because the answer decides whether there is an appeal worth filing.
See what your claims are leaving behind
Send us a month of remittance data and we will tell you what it says: which codes are being denied, how much of it is recoverable, and how long your money is sitting in A/R. It takes about a week and there is nothing to sign.