The CO-298 denial code means the medical plan has no benefit for the service and has already forwarded your claim to the patient’s vision plan. You usually do not need to refile. Post the medical zero, confirm that the vision plan received the claim, and wait for its remittance. (Primary source: X12 Claim Adjustment Reason Codes)
In brief: CARC 298 is a handoff notice. The medical plan did the routing work for you. A second claim to the vision plan can create a duplicate, so track the forwarded one first.
Part of our denial codes library. Written by Manikandan J, CPC, CRCR, who has tracked forwarded eyewear and eye exam claims for optical shops and eye clinics. Published 15 November 2026. Last updated: 15 November 2026. Code wording quoted word for word from X12. Read about the author and our editorial policy, or contact us to report an error.
What does denial code CO-298 mean?
Denial code CO-298 means the medical plan passed your claim to the vision plan. Reason code 298 appears when one carrier, or two linked carriers, manage both benefits. The medical zero is a routing step, not a final denial of the service.
| Field | Value |
|---|---|
| Code | 298 |
| Description | “Claim received by the medical plan, but benefits not available under this plan. Claim has been forwarded to the patient’s vision plan for further consideration.” |
| Group codes | No X12 group restriction; CO and OA both appear |
| Start | 03/01/2019 |
| Twin code | CARC 297 when you must submit to the vision plan yourself |
Source: X12 Claim Adjustment Reason Codes, checked 15 November 2026.
Methodology: the code wording is copied from the X12 list, and the claim form steps follow the NUCC instructions cited below.
Key terms: A forwarded claim is one the payer sends to another plan for you. A crossover is the general term for that automatic handoff. CO is the contractual obligation group code.
CO-298 vs OA-298: what is the difference?
CO-298 records the medical zero as a contractual adjustment while the claim moves to vision. OA-298 shows the same handoff with no liability assigned. The practical next step is identical: hold the balance in a forwarded status and wait for the vision plan’s decision.
| Version | Posting on the medical remit | Patient balance now? |
|---|---|---|
| CO-298 | Zero paid, contract adjustment, status forwarded to vision | No |
| OA-298 | Zero paid, other adjustment, status forwarded to vision | No |
Why was my claim forwarded to the vision plan?
Your claim was forwarded because the medical plan recognized a vision service and already had the patient’s vision coverage on file. Eyeglass frames, lenses, contact lenses and routine exams are typical examples. Medical plans often exclude these items, and the Medicare routine eye exam page shows Medicare excludes most of them.
Forwarding needs a link between the two plans. When there is no link, the plan uses CARC 297 instead, and you file with the vision plan yourself. That difference is the whole reason both codes exist on the X12 CARC list.
Example scenario (fictional names), part 1
CO-298 Denial Example: What Happened
Priya Nandakumar runs billing at Clearview Optical, an optical shop beside an eye clinic. A patient picked up new single vision lenses and a frame. Priya billed V2100 and V2020 with diagnosis H5213 to the patient’s medical plan, which shares a carrier with the vision plan.
The 835 returned CAS*CO*298 on both lines, with a zero payment. Three weeks later, no vision remit had arrived. A coworker suggested sending a fresh claim to the vision plan.
Was a new claim the right move, or would it cause trouble? Keep reading, or jump to how it was resolved. Keep reading, or jump to how the CO-298 denial was resolved.
How do I handle a CO-298 denial?
To handle a CO-298 denial, confirm the forward instead of refiling. Call the vision plan or check its portal for the forwarded claim. If it is there, answer any record request and wait. If the vision plan has no record, ask the medical plan for the forward date, then file directly.
- Post the medical zero with a note that says forwarded to vision.
- Check the vision portal for the claim after a reasonable wait, such as two weeks.
- Answer requests for the prescription or order, if the vision plan asks.
- File directly only if lost, and keep proof of the medical plan’s forward date.
- Bill the patient only for the share on the vision plan’s remittance.
Example scenario (fictional names), part 2
How the CO-298 Denial Was Resolved
Priya called the vision plan before sending anything. The representative located the forwarded claim, which was pending for a missing lens prescription date. No correspondence had reached the optical shop yet.
Fix: Priya faxed the lens prescription with its date to the vision plan. She did not send a new claim. She logged the call reference and set a two-week follow-up.
Outcome: the vision plan paid the lenses and frame under the patient’s eyewear benefit. Priya now checks the vision portal one week after every CO-298 remit.
Names and details are illustrative; no real patient data.
Names and details are illustrative; no real patient data.
Should I send a new claim after CO-298?
No, not at first. The vision plan already has the claim, so a second one may come back as a duplicate, like CO-18. Send a direct claim only when the vision plan confirms it has no record. Keep the medical remit as proof of timely filing. The NUCC 1500 instructions explain the insurance boxes if you must file.
Can I bill the patient for CO-298?
No, not for the medical plan’s zero. Wait for the vision plan’s decision first. The patient may then owe a copayment or the cost above an eyewear allowance, exactly as that separate policy’s remittance shows.
Related codes
| Code | Meaning |
|---|---|
| CO-291 | Medical plan forwarded the claim to the dental plan |
| CO-292 | Medical plan forwarded the claim to the pharmacy plan |
| CO-18 | Exact duplicate claim or service |
| CO-109 | Service not covered by this payer; send to the correct payer |
FAQ
What does CO-298 mean?
The medical plan has no benefit and already forwarded the claim to the vision plan.
How is CO-298 different from CO-297?
With CO-298 the plan forwarded the claim. With CO-297 you must send it yourself.
Do I need to refile a CO-298 claim?
Usually not. Confirm the vision plan received it, then wait for its remit.
Which group code comes with CARC 298?
X12 sets no restriction. CO and OA both appear on forwarding notices.
When can I bill the patient after CO-298?
Only after the vision plan’s remit shows a patient share.
Sources
How we checked: the CARC 298 quote was matched word for word with the X12 CARC list on 15 November 2026.
- X12, Claim Adjustment Reason Codes (CARC 298, 297, 18). Accessed 15 Nov 2026.
- X12, Remittance Advice Remark Codes. Accessed 15 Nov 2026.
- NUCC, 1500 claim form instructions. Accessed 15 Nov 2026.
- Medicare.gov, eye exams (routine). Accessed 15 Nov 2026.
Last updated: 15 November 2026 · Educational content; not legal advice.