OA-18Other AdjustmentDuplicate
OA-18 Denial Code: Duplicate claim (other adjustment)
Exact duplicate claim/service reported with the Other Adjustment group code.
Why OA-18 happens
- ●Same as CO-18 — duplicate submission before original adjudicated
How to fix a OA-18 denial
- 1
Check the status of the original claim before any resubmission
- 2
Use repeat modifiers if services were distinct
How to prevent it
Status-check instead of rebilling.
Drowning in OA-18 denials?
OakClaim works every denial within 48 hours and builds prevention rules so they stop recurring.