Authorization exceeded
An authorization exists, but the claim asks for more visits, units, days or a date outside what was approved.
CO = Contractual Obligation. The provider owes the difference. The patient cannot be billed for this amount. The same reason code can appear with a different group code; the group decides who may be billed.
Usual causes
- More visits used than authorized (therapy, behavioral health).
- Date of service after the authorization end date.
- Units on the claim exceed the authorized units.
The fix
Compare the claim to the authorization letter. If the claim is wrong, correct it. If more services were needed, request an extension or additional units (retroactive where allowed) and resubmit. Track remaining authorized visits in the scheduling system.
Appeal or corrected claim?
Corrected claim for a data error; authorization extension plus resubmission when more services were needed; appeal with clinical notes if the payer refuses the extension.
Deadline to watch
Extension requests often must be made within days of the last authorized visit; timely filing still applies.
Exact limits are in your payer contract or provider manual. When in doubt, send the correction or appeal this week.
CO-198 in short
What does CO-198 mean?
An authorization exists, but the claim asks for more visits, units, days or a date outside what was approved. The official X12 text reads: "Precertification/notification/authorization/pre-treatment exceeded."
What usually causes a CO-198 denial?
More visits used than authorized (therapy, behavioral health). Date of service after the authorization end date. Units on the claim exceed the authorized units.
How do I fix CO-198?
Compare the claim to the authorization letter. If the claim is wrong, correct it. If more services were needed, request an extension or additional units (retroactive where allowed) and resubmit. Track remaining authorized visits in the scheduling system.
Should I appeal CO-198 or send a corrected claim?
Correct or appeal (see note). Corrected claim for a data error; authorization extension plus resubmission when more services were needed; appeal with clinical notes if the payer refuses the extension.
What deadline applies to CO-198?
Extension requests often must be made within days of the last authorized visit; timely filing still applies.