Home Denial Codes 163
Denial Code 163

Attachment referenced on the claim was not received (Updated for 2026)

Attachment referenced on the claim was not received

Quick Explanation

Denial code 163 indicates that the payer processed a claim containing an attachment indicator but did not successfully receive or match the supporting medical documentation required to adjudicate the services. This typically occurs when clinical notes, operative reports, or certificates of medical necessity referenced in the claim submission are not received within the payer's designated matching window.

Common Causes for 163

Denials with code 163 typically happen for the following specific reasons:

How to Prevent 163 Denials

To avoid receiving this denial in the future, implement these specific checks:

Appeal Letter Template for 163

If you believe this claim was denied incorrectly, you can use the following template to submit an appeal.

[Your Practice Header]
[Date]

[Payer Name]
[Appeals Department Address]

RE: Appeal for Claim [Claim Number]
Patient: [Patient Name]
ID: [Patient ID]
Date of Service: [Date]
Denial Code: 163 - Attachment referenced on the claim was not received

Dear Appeals Department,

I am writing to appeal the denial of the above-referenced claim, which was denied with code 163: "Attachment referenced on the claim was not received".

We are writing to appeal the denial of this claim under denial code 163. In accordance with CMS guidelines and HIPAA administrative standards regarding electronic claims and supporting documentation (PWK segment), we are enclosing the complete, requested medical documentation, including clinical notes and operative reports, to support the services billed. Please associate these enclosed records with Claim Control Number [Insert Claim Control Number] and reprocess the claim for immediate adjudication and payment as contractually required.

Attached please find:
1. A copy of the original claim.
2. The relevant medical records supporting the service.
3. [Any other supporting documents].

We respectfully request that you reprocess this claim for payment.

Sincerely,

[Your Name]
[Title]
[Practice Name]
            

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