CO-151 denial code
The payer thinks the documentation doesn't support this many services, or services this often.
“Payment adjusted because the payer deems the information submitted does not support this many/frequency of services.”
Start 10/31/2002 · Last modified 01/27/2008 · X12 adjustment reason code list
What it usually means in behavioral health
CO-151 shows up when session frequency outruns what the plan expects or authorized: more than one psychotherapy session in a day or week, ABA hours above the weekly authorization, or group sessions counted differently than the contract expects.
Common causes
- Weekly psychotherapy frequency above the plan's policy without supporting documentation
- ABA units above the authorized weekly amount
- The same service billed twice on one date without documentation of separate sessions
- Frequency limits in the plan's policy that the team didn't know about
Correct and resubmit, or appeal?
If a billing error doubled units or sessions, correct it. If the frequency was clinically necessary, appeal with documentation showing why, such as acuity, crisis episodes, or a treatment plan calling for that frequency.
What to do
Count the sessions or units billed against the authorization and the plan's frequency policy.
Correct duplicates or unit errors.
For clinically necessary frequency, appeal with the treatment plan and notes that justify it.
Often seen with
- N362
- N640
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