CO-252Contractual ObligationDocumentation
CO-252 Denial Code: Attachment/documentation required
An attachment or other documentation is required to adjudicate this claim/service.
Why CO-252 happens
- ●Payer needs operative notes, invoices, or medical records
- ●Unlisted code billed without a description/report
How to fix a CO-252 denial
- 1
Identify the required documentation from the remark code
- 2
Submit records via the payer's attachment process and resubmit/respond
How to prevent it
Attach required documentation proactively for codes that always need it (unlisted, high-dollar).
Drowning in CO-252 denials?
OakClaim works every denial within 48 hours and builds prevention rules so they stop recurring.