Guidelines › Combination codes
Combination codes
Official text from the FY2027 ICD-10-CM Official Guidelines for Coding and Reporting. The wording is quoted exactly.
Guidelines I.B.9
“Assign only the combination code when that code fully identifies the diagnostic conditions involved or when the Alphabetic Index so directs.”
“When the combination code lacks necessary specificity in describing the manifestation or complication, an additional code should be used as a secondary code.”
Where this applies
This is a general rule. It applies to code assignment everywhere, not to one code or group of codes.
The Guidelines are the authority for assigning codes, and following them is required under HIPAA. This page quotes them for convenience and is not a substitute for the official document. See the Terms and Disclaimer.