2026 ICD-10-CM Diagnosis Code J11.1Influenza due to unidentified influenza virus with other respiratory manifestations

ICD-10-CM Codes›J00–J99›J09-J18›J11

ICD-10-CM J11.1
CMSSource: CMS FY 2026 ICD-10-CM dataset · Effective Oct 1, 2025 – Sep 30, 2026

J11.1 is a billable ICD-10-CM diagnosis code for influenza due to unidentified influenza virus with other respiratory manifestations. It is valid on HIPAA claims for fiscal year 2026 (October 1, 2025 through September 30, 2026) and groups to MS-DRG 152 through 153. Coders also document this condition as bronchiolitis caused by influenza virus. In AHRQ's Clinical Classifications Software (CCSR), this diagnosis falls under Influenza.

Code Identity

ICD-10-CM Code
J11.1
Billable Status
Yes — Valid for Submission
Code Describes
Influenza due to unidentified influenza virus with other respiratory manifestations
Short Description
Flu due to unidentified influenza virus w oth resp manifest
Parent Code
J11
Influenza due to unidentified influenza virus

Code Classification

ChapterJ00–J99Diseases of the respiratory system
SectionJ09-J18Influenza and pneumonia
CategoryJ11Influenza due to unidentified influenza virus
This CodeJ11.1Influenza due to unidentified influenza virus with other respiratory manifestations

Approximate SynonymsGuidance

Alternate terms and clinical phrases that map to this code.

  • Bronchiolitis caused by influenza virus
  • Healthcare associated influenza disease
  • Inflammation of larynx caused by virus
  • Influenza
  • Influenza caused by seasonal influenza virus
  • Influenza with laryngitis
  • Influenza with pharyngitis
  • Influenzal acute upper respiratory infection
  • Upper respiratory tract infection caused by influenza virus

Tabular List NotesGuidance

Coding notes and annotation back-references applicable to this code.

Inclusion Terms

  • Influenza NOS
  • Influenzal laryngitis NOS
  • Influenzal pharyngitis NOS
  • Influenza with upper respiratory symptoms NOS

Use Additional Code

  • code for associated pleural effusion, if applicable J91.8

Index to Diseases and InjuriesGuidance

Alphabetical index entries that point to this code.

External Cause of Injuries IndexGuidance

References for this code in the External Cause of Injuries Index.

    • Influenza(bronchial) (epidemic) (respiratory (upper)) (unidentified influenza virus)
    • Influenza(bronchial) (epidemic) (respiratory (upper)) (unidentified influenza virus)
      • with
        • laryngitis
    • Influenza(bronchial) (epidemic) (respiratory (upper)) (unidentified influenza virus)
      • with
        • pharyngitis
    • Influenza(bronchial) (epidemic) (respiratory (upper)) (unidentified influenza virus)
      • with
        • respiratory manifestations NEC

Clinical ClassificationClinical

AHRQ’s CCSR groups this code into broader clinical categories.

CCSR RSP003
Influenza
Default principal diagnosis: inpatient Yes · outpatient Yes

Clinical InformationClinical

  • Viral Laryngitis

    acute inflammation of the larynx caused by viruses, including rhinovirus, influenza virus, parainfluenza virus, and adenovirus.

Patient EducationClinical

Flu

The flu, also called influenza, is a respiratory infection caused by viruses. Each year, millions of Americans get sick with the flu. Sometimes it causes mild illness. But it can also be serious or even deadly, especially for people over 65, newborn babies, and people with certain chronic illnesses.

The full article covers:

  • What is the flu?
  • What causes the flu?
  • What are the symptoms of the flu?
  • What other problems can the flu cause?
  • How is the flu diagnosed?
  • What are the treatments for the flu?
  • Can the flu be prevented?

Read the full article at MedlinePlus

Courtesy of MedlinePlus, a service of the U.S. National Library of Medicine.

Convert J11.1 to ICD-9-CMHistory

The closest ICD-9-CM equivalents under the General Equivalence Mappings.

ICD-9-CM
487.1 Flu w resp manifest NEC
Approximate The match is approximate rather than exact.

Code HistoryHistory

FY 2016AddedAdded to the ICD-10-CM code setEffective October 1, 2015, the first year of ICD-10-CM.
FY 2017–2025No changes
FY 2026CurrentCurrent code set, no changesEffective October 1, 2025 through September 30, 2026.

Questions About J11.1Overview

Is J11.1 (Influenza due to unidentified influenza virus) a billable code?

Yes. This is a billable ICD-10-CM code, specific enough to report influenza due to unidentified influenza virus with other respiratory manifestations on HIPAA-covered claims from October 1, 2025 through September 30, 2026.

What MS-DRG does J11.1 group to?

When influenza due to unidentified influenza virus with other respiratory manifestations is the principal diagnosis on an inpatient stay, it groups to MS-DRG 152, 153, with relative weights from 0.7382 to 1.1822 depending on complications. Higher weights mean higher Medicare reimbursement.

What is the ICD-9 equivalent of J11.1?

Under the General Equivalence Mappings, influenza due to unidentified influenza virus with other respiratory manifestations converts to ICD-9-CM 487.1 (flu w resp manifest NEC). The mapping is approximate, so confirm the match fits the documentation.

Footnotes

[1] Not chronic - A diagnosis code that does not fit the criteria for chronic condition (duration, ongoing medical treatment, and limitations) is considered not chronic. Some codes designated as not chronic are acute conditions. Other diagnosis codes that indicate a possible chronic condition, but for which the duration of the illness is not specified in the code description (i.e., we do not know the condition has lasted 12 months or longer) also are considered not chronic.