CO-90Contractual ObligationPayment Adjustment
CO-90 Denial Code: Ingredient cost adjustment (pharmacy)
Pharmacy-only adjustment to the drug ingredient cost versus the billed amount.
Why CO-90 happens
- ●Billed ingredient cost exceeded the payer's pricing benchmark (AWP/NADAC-based)
How to fix a CO-90 denial
- 1
Reconcile against the contract's pricing source; dispute if the benchmark was misapplied
How to prevent it
Keep pharmacy pricing files synchronized with contract benchmarks.
Drowning in CO-90 denials?
OakClaim works every denial within 48 hours and builds prevention rules so they stop recurring.