How do I resolve a CO-198 denial?

Retrieve the original authorization or precertification approval notice: Verify the exact units, dates, or dollar amounts that were authorized to determine if payer correctly identified an overage Compare authorization limits to billed services line-by-line: Identify whether the claim truly exceeded authorization or if payer miscalculated units, dates of service, or authorization scope If authorization was sufficient, prepare appeal with authorization documentation: Submit appeal with copy of authorization showing approved limits match or exceed the billed services If authorization was insufficient, determine if additional authorization was obtained or should have been requested: If additional authorization exists but was not referenced, resubmit with correct authorization number; if never obtained, accept write-off or implement future authorization monitoring Document authorization tracking gaps and update intake workflows: Prevent recurrence by implementing alerts when nearing authorization limits during active treatment

835 Denial Combination

CO-198

Contractual Obligation · Service-Line Level Adjustment

Authorization

What This Combination Means

Services were authorized but the billed units or amount exceeded the authorized quantity or dollar limit. The excess amount is subject to contractual write-off rather than patient billing. This typically occurs when authorization specified a maximum number of visits, units, or treatment sessions and the claim exceeded that approved scope.

Financial Responsibility

provider writeoff

The provider is contractually obligated to write off the amount exceeding the authorized scope. The patient cannot be billed for services that exceed precertification limits under the CO group code.

55%

Appeal Success

45-60 days (appeal process)

Avg. Resolution

Hard

Difficulty

Yes

Appealable

Step-by-Step Resolution

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

Appealable:Authorization denials are appealable if the provider believes the authorization was properly obtained for the full scope billed, or if the authorization limits were incorrectly applied by the payer.

1
Retrieve the original authorization or precertification approval notice
Verify the exact units, dates, or dollar amounts that were authorized to determine if payer correctly identified an overage
2
Compare authorization limits to billed services line-by-line
Identify whether the claim truly exceeded authorization or if payer miscalculated units, dates of service, or authorization scope
3
If authorization was sufficient, prepare appeal with authorization documentation
Submit appeal with copy of authorization showing approved limits match or exceed the billed services
4
If authorization was insufficient, determine if additional authorization was obtained or should have been requested
If additional authorization exists but was not referenced, resubmit with correct authorization number; if never obtained, accept write-off or implement future authorization monitoring
5
Document authorization tracking gaps and update intake workflows
Prevent recurrence by implementing alerts when nearing authorization limits during active treatment

Specialty Context

How CO-198 typically presents across different practice types.

Dental

Common with multi-visit treatment plans where authorization approved a specific number of procedures (e.g., 4 crowns approved but 5 billed), or orthodontic phase limits exceeded

Medical

Frequently occurs with physical therapy, occupational therapy, home health, durable medical equipment rentals, or chemotherapy infusions where visit counts or unit quantities exceed pre-authorized limits

Behavioral Health

Common in outpatient therapy or intensive outpatient programs where authorization specified a set number of sessions (e.g., 20 sessions approved but 25 billed) or residential treatment day limits exceeded

Individual Code References

View the standalone definition for each code in this combination.

CARC 198

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Synthesized from official definitions — not from training data

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