ICD-10 Code J42 – Unspecified chronic bronchitis (2026): Diagnosis, Symptoms & Billing Guide
2026 ICD-10-CM Diagnosis Code J42 – Unspecified chronic bronchitis
What it is
J42 identifies chronic bronchitis when the record does not specify whether it is simple, mucopurulent, or another defined type. Use it for a long-standing bronchial inflammation documented as chronic and unspecified.
Clinical signs
Typical findings include a persistent productive cough, chronic sputum, and recurrent airway irritation. Clinical features vary; refer to documentation, especially when the note does not name a more specific chronic bronchitis type.
When to use this code
Use J42 when the provider documents chronic bronchitis without further detail and no more specific COPD or bronchitis code is supported. It also fits cases where the chart confirms chronic bronchitis but does not describe the form or cause. Check documentation if asthma, COPD, or emphysema is also mentioned.
Do not use for
Do not use J42 for acute bronchitis, bronchitis with a specific subtype, or chronic obstructive pulmonary disease that is separately documented and coded. Do not assign it when the note provides a more specific diagnosis.
Coding tip
If the record says only “chronic bronchitis,” J42 is appropriate unless the documentation supports a more specific code.