CO-252: An attachment/other documentation is required to adjudicate this claim/service.

Why it fires

• The payer's policy requires documentation for this code or procedure type, such as unlisted codes, high-dollar DME, or certain modifiers
• The claim was submitted without the required attachment or with an incomplete one
• The payer flagged the claim for pre-payment review requiring records

Corrective actions, ranked

1. 1

   Identify exactly what is needed

   Check the remark code or payer correspondence for the specific document requested, such as an op note, letter of medical necessity, or invoice.

2. 2

   Submit the documentation promptly

   Send the requested records through the payer's preferred method, such as portal, fax, or mail, referencing the claim number.

3. 3

   Track the resubmission

   Follow up to confirm the documentation was received and matched to the claim before the timely filing or appeal window closes.

Is it worth appealing

This is really a documentation request rather than a final denial. Submitting complete records promptly typically resolves it without a formal appeal.

Other denial codes to check

Codes that share a remark code with this one, or that are reported under the same group code.

• CO-45Charge exceeds fee schedule/maximum allowable or contracted/legislated fee arrangement.
• CO-97The benefit for this service is included in the payment/allowance for another service/procedure that has already been adjudicated.
• CO-16Claim/service lacks information or has submission/billing error(s).
• CO-11The diagnosis is inconsistent with the procedure.
• OA-18Exact duplicate claim/service (Use only with Group Code OA except where state workers' compensation regulations requires CO)
• CO-29The time limit for filing has expired.

See every CARC in the dataset