How do I resolve a CO-198 denial?

Pull the original prior authorization to confirm the exact authorized units/visits/services. Compare authorized quantity to the amount billed on the denied claim. If you have a valid reason for exceeding the auth (clinical necessity): contact the payer to request a retro-auth amendment adding the additional units. If the retro-auth amendment is approved, resubmit the claim with the revised authorization. If the excess is a billing error: correct the units billed to match the authorized amount and resubmit. Implement a workflow to verify remaining authorized units before scheduling additional services.

Can I appeal a CO-198 denial?

Yes. CO-198 denials are typically appealable with a 55% success rate. Resolution difficulty is Medium and typically takes 14-30 days.

835 Denial Combination

CO-198

Contractual Obligation · Service-Line Level Adjustment

What This Combination Means

The number of units, visits, or services billed exceeds the amount authorized. The service required prior authorization, authorization was obtained, but the claim exceeds the authorized quantity. The excess units are denied.

55%

Appeal Success

14-30 days

Avg. Resolution

Medium

Difficulty

Yes

Appealable

Step-by-Step Resolution

Steps tailored specifically to this CO-198 combination — not generic advice.

1
Pull the original prior authorization to confirm the exact authorized units/visits/services.
2
Compare authorized quantity to the amount billed on the denied claim.
3
If you have a valid reason for exceeding the auth (clinical necessity): contact the payer to request a retro-auth amendment adding the additional units.
4
If the retro-auth amendment is approved, resubmit the claim with the revised authorization.
5
If the excess is a billing error: correct the units billed to match the authorized amount and resubmit.
6
Implement a workflow to verify remaining authorized units before scheduling additional services.

Specialty Context

How CO-198 typically presents across different practice types.

Dental

For procedures authorized per unit (e.g., fluoride varnish, sealants), confirm the billed units match the authorized quantity. Over-billing units without a corresponding auth amendment is the most common cause.

Medical

Surgery or physical therapy claims often have unit limits. If additional units were medically necessary beyond what was authorized, request a retroactive authorization amendment before resubmitting.

Behavioral Health

Session counts are tightly managed. If a patient received more sessions than authorized, request a concurrent review or auth extension retroactively and resubmit with the expanded auth number.

Individual Code References

View the standalone definition for each code in this combination.

CARC 198

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