How to Appeal CO-198 Denial: Precertification/authorization exceeded
The amount, frequency, or duration of services billed exceeded the scope of the prior authorization granted. This guide explains what it means, why it happens, and exactly how to build a winning appeal.
Ready to appeal this denial?
Upload your EOB and get a professionally drafted appeal letter in 60 seconds — free.
What Does CO-198 Mean?
The amount, frequency, or duration of services billed exceeded the scope of the prior authorization granted.
Commonly seen in:
Step-by-Step Appeal Guide for CO-198
- 1
Locate any authorization number, date requested, or confirmation from the payer
- 2
Gather clinical documentation supporting the medical necessity of the service
- 3
Obtain records of any calls to the payer (dates, reference numbers, rep names)
- 4
Draft the appeal citing state retroactive authorization laws if applicable
- 5
Submit with documentation and follow up within 5 business days
Counter-Arguments to Use in Your Appeal
These are the strongest arguments medical billing professionals use to overturn CO-198 denials.
Document the clinical reasons for exceeding the authorized amount
Request a concurrent review or authorization extension with supporting documentation
Provide evidence that the additional services were medically necessary and not foreseeable
Cite state laws requiring coverage when medical necessity extends beyond the original auth
Regulations and Guidelines to Cite
Citing specific regulations strengthens your appeal and demonstrates you know your rights.
Expert Tip for CO-198 Appeals
Request concurrent reviews proactively when you anticipate exceeding the authorized amount. Retroactive requests are harder to win.
Frequently Asked Questions
What is a CO-198 denial code?
The amount, frequency, or duration of services billed exceeded the scope of the prior authorization granted.
Can I appeal a CO-198 denial?
Yes. All insurance denials are appealable. Authorization denials can often be overturned with retroactive auth requests. Follow the step-by-step guide above and submit your appeal before the payer's deadline, typically 180 days from the denial date.
What documentation do I need to appeal CO-198?
For a CO-198 denial, you typically need: the original denial letter/EOB, clinical documentation supporting the service, any prior authorization records, and a cover letter citing the relevant regulations listed above. The specific documents depend on why the denial was issued.
How long does a CO-198 appeal take?
Most payers are required to process standard appeals within 30–60 days. Expedited appeals (for urgent care) must be decided within 72 hours. Under ERISA, group health plans must provide an appeal decision within 60 days for pre-service and 60 days for post-service claims.
Generate Your CO-198 Appeal Letter
Upload your denial letter and AppealAI will generate a professionally drafted, regulation-cited appeal letter in 60 seconds — free during beta.
Generate Your Appeal Letter Free →No account required. Free during beta. Draft generates in under 60 seconds.