J11 Influenza due to unidentified influenza virus
The ICD-10-CM code for Influenza due to unidentified influenza virus is J11 (FY2026). It is a non-billable category code — select a more specific code below for claims.
Classification
- Section
- J09-J18: Influenza and pneumonia (J09-J18)
- Category J11
- 11 codes (8 billable)
- FY2026 Status
- Stable since FY2024
Official Coding Guidelines
Influenza: code confirmed J09/J10; suspected/probable use J11c. Influenza due to certain identified influenza viruses Code only confirmed cases of influenza due to certain identified influenza viruses (category J09), and due to other identified influenza virus (category J10). This is an exception to the hospital inpatient guideline Section II, H. (Uncertain Diagnosis). In this context, “confirmation” does not require documentation of positive laboratory testing specific for avian or other novel influenza A or other identified influenza virus. However, coding should be based on the provider’s diagnostic statement that the patient has avian influenza, or other novel influenza A, for category J09, or has another particular identified strain of influenza, such as H1N1 or H3N2, but not identified as novel or variant, for category J10. If the provider records “suspected” or “possible” or “probable” avian influenza, or novel influenza, or other identified influenza, then the appropriate influenza code from category J11, Influenza due to unidentified influenza virus, should be assigned. A code from category J09, Influenza due to certain identified influenza viruses, should not be assigned nor should a code from category J10, Influenza due to other identified influenza virus.
COPD/asthma: acute exacerbation vs uncomplicateda. Chronic Obstructive Pulmonary Disease [COPD] and Asthma 1) Acute exacerbation of chronic obstructive bronchitis and asthma The codes in categories J44 and J45 distinguish between uncomplicated cases and those in acute exacerbation. An acute exacerbation is a worsening or a decompensation of a chronic condition. An acute exacerbation is not equivalent to an infection superimposed on a chronic condition, though an exacerbation may be triggered by an infection.
Source: CMS — ICD-10-CM Official Guidelines for Coding and Reporting, FY2026