2027 ICD-10-CM Diagnosis Code J42Unspecified chronic bronchitis
ICD-10-CM Codes›J00–J99›J40-J4B›J42
- Billable — Valid for Submission
- Risk Adjusts — HCC 280
- Chronic Condition
J42 is a billable ICD-10-CM diagnosis code for unspecified chronic bronchitis. It is valid on HIPAA claims for fiscal year 2027 (October 1, 2026 through September 30, 2027) and groups to MS-DRG 190 through 192. In AHRQ's Clinical Classifications Software (CCSR), this diagnosis falls under Chronic obstructive pulmonary disease and bronchiectasis.
For Medicare Advantage risk adjustment, J42 maps to CMS-HCC Category 280 (Chronic Obstructive Pulmonary Disease, Interstitial Lung Disorders, and Other Chronic Lung Disorders) under the V28 model, adding a risk factor of about 0.319 for a community, non-dual, aged beneficiary in payment year 2027.
Code Identity
Code Classification
Medicare Risk Adjustment (HCC)Billing
J42 maps to a payment category in the CMS-HCC model used to risk-adjust Medicare Advantage payments. Weights are the published community factors for payment year 2027.
Source: CMS Payment Year 2027 risk adjustment mappings and model software. Weights are relative factors, not dollar amounts; a beneficiary's total RAF also includes demographics and interactions. Browse all CMS-HCC categories.
Approximate SynonymsGuidance
Alternate terms and clinical phrases that map to this code.
- Bronchiolitis obliterans syndrome due to and after lung transplantation
- Bronchitis
- Bronchitis co-occurrent with acute wheeze
- Bronchitis co-occurrent with chronic wheeze
- Bronchitis co-occurrent with wheeze
- Chronic bronchiolitis
- Chronic bronchitis
- Chronic bronchitis co-occurrent with wheeze
- Chronic graft-versus-host disease
- Chronic obliterative bronchiolitis
- Chronic tracheitis
- Chronic tracheobronchitis
- Eosinophilic bronchitis
- Fetid chronic bronchitis
- Infectious disorder of bronchus
- Protracted bronchitis caused by bacterium
- Recurrent bronchitis
- Recurrent bronchopulmonary infection
- Recurrent lower respiratory tract infection
- Septic bronchitis
- Tracheobronchitis
Instructional NotesGuidance
Instructions from the official ICD-10-CM Tabular List that apply to J42: its own notes plus those printed at block J40-J4B and Chapter 10. A note printed at a category, block or chapter applies to every code under it.
Applicable To
Conditions this code is used for: synonyms of the title or, for "other specified" codes, the conditions assigned to it. The list is not exhaustive.
- Chronic bronchitis NOS
- Chronic tracheitis
- Chronic tracheobronchitis
Excludes1
Not coded here: the excluded code is never reported together with this one, unless the two conditions are unrelated.
- bronchitis due to chemicals, gases, fumes and vapors (J68.0)
Excludes2
Not included here: the excluded condition is not part of this code, but a patient may have both, so both codes may be reported.
- cystic fibrosis (E84.-)
- certain conditions originating in the perinatal period (P04-P96)
- certain infectious and parasitic diseases (A00-B99)
- complications of pregnancy, childbirth and the puerperium (O00-O9A)
- congenital malformations, deformations and chromosomal abnormalities (Q00-Q99)
- endocrine, nutritional and metabolic diseases (E00-E88)
- injury, poisoning and certain other consequences of external causes (S00-T88)
- neoplasms (C00-D49)
- smoke inhalation (T59.81-)
- symptoms, signs and abnormal clinical and laboratory findings, not elsewhere classified (R00-R94)
Code Also
A second code may be needed to fully describe the condition; the note gives no sequencing direction.
- if applicable, chronic respiratory conditions due to chemicals, gases, fumes and vapors (J68.4)
Notes
General instructions on how these codes are used.
- When a respiratory condition is described as occurring in more than one site and is not specifically indexed, it should be classified to the lower anatomic site (e.g. tracheobronchitis to bronchitis in J40).
Source: CMS ICD-10-CM Tabular List. How to read instructional notes.
Referenced in Other NotesGuidance
Instructional notes printed at other codes that name J42, its category, or a range that includes it.
Applicable To 1
These notes mention J42.
- Z82.5 Family history of asthma and other chronic lower respiratory diseases
Excludes1 1
These codes carry an Excludes1 note naming J42: they are not reported together with it, unless the two conditions are unrelated.
- J37.1 Chronic laryngotracheitischronic tracheitis (J42)
Excludes2 7
These codes carry an Excludes2 note naming J42: its condition is not part of those codes, and both may be reported when the patient has both.
- J04.1 Acute tracheitischronic tracheitis (J42)
- J20 Acute bronchitischronic bronchitis NOS (J42)
- J20 Acute bronchitischronic tracheobronchitis (J42)
- J41 Simple and mucopurulent chronic bronchitischronic bronchitis NOS (J42)
- J44 Other chronic obstructive pulmonary diseasechronic bronchitis NOS (J42)
- J44 Other chronic obstructive pulmonary diseasechronic tracheitis (J42)
- J44 Other chronic obstructive pulmonary diseasechronic tracheobronchitis (J42)
Index to Diseases and InjuriesGuidance
Alphabetical index entries that point to this code.
Clinical ClassificationClinical
AHRQ’s CCSR groups this code into broader clinical categories.
Clinical InformationClinical
Chronic Bronchitis
a type of chronic obstructive pulmonary disease characterized by chronic inflammation in the bronchial tree that results in edema, mucus production, obstruction, and reduced airflow to and from the lung alveoli. the most common cause is tobacco smoking. signs and symptoms include coughing with excessive mucus production, and shortness of breath.
Patient EducationClinical
Chronic Bronchitis
Chronic bronchitis is a type of COPD (chronic obstructive pulmonary disease). COPD is a group of lung diseases that make it hard to breathe and get worse over time. The other main type of COPD is emphysema. Most people with COPD have both emphysema and chronic bronchitis, but how severe each type is can be different from person to person.
The full article covers:
- What is chronic bronchitis?
- What causes chronic bronchitis?
- Who is at risk for chronic bronchitis?
- What are the symptoms of chronic bronchitis?
- How is chronic bronchitis diagnosed?
- What are the treatments for chronic bronchitis?
- Can chronic bronchitis be prevented?
Read the full article at MedlinePlus
Courtesy of MedlinePlus, a service of the U.S. National Library of Medicine.
Convert J42 to ICD-9-CMHistory
The closest ICD-9-CM equivalents under the General Equivalence Mappings.
Code HistoryHistory
Questions About J42Overview
What is the ICD-10 code for unspecified chronic bronchitis?
The ICD-10-CM code for unspecified chronic bronchitis is J42. It is billable on HIPAA-covered claims from October 1, 2026 through September 30, 2027.
Is J42 (Unspecified chronic bronchitis) a billable code?
Yes. This is a billable ICD-10-CM code, specific enough to report unspecified chronic bronchitis on HIPAA-covered claims from October 1, 2026 through September 30, 2027.
What MS-DRG does J42 group to?
When unspecified chronic bronchitis is the principal diagnosis on an inpatient stay, it groups to MS-DRG 192, 190, 191, with relative weights from 0.6285 to 1.0749 depending on complications. Higher weights mean higher Medicare reimbursement.
Can J42 be reported with J44.81?
Not as a rule. The Excludes1 note on J42 lists "bronchiolitis obliterans and bronchiolitis obliterans syndrome (J44.81)". An Excludes1 note means the excluded code is never reported together with this one; the only exception is when the two conditions are unrelated to each other (Official Guidelines, Section I.A.12.a).
Does J42 need an additional code?
When the condition applies, yes. The Use Additional Code note reads: code to identify: exposure to environmental tobacco smoke (Z77.22); exposure to tobacco smoke in the perinatal period (P96.81); history of tobacco dependence (Z87.891); occupational exposure to environmental tobacco smoke (Z57.31); tobacco dependence (F17.-); and 1 more listed in the Instructional Notes section. The additional code is reported after J42.
What HCC is J42?
J42 (unspecified chronic bronchitis) maps to CMS-HCC Category 280 (Chronic Obstructive Pulmonary Disease, Interstitial Lung Disorders, and Other Chronic Lung Disorders), commonly written as HCC 280, in the CMS-HCC V28 model used for Medicare Advantage risk adjustment in payment year 2027. It mapped to HCC 111 under the retired V24 model. It also maps in the PACE (CMS-HCC V22), ESRD (V21), and ESRD (V24) models. In the Part D prescription drug model it maps to RxHCC 229.
Does J42 risk-adjust for Medicare Advantage payment?
Yes. When documented and reported on a Medicare Advantage encounter, J42 adds a risk adjustment factor of about 0.319 to the beneficiary's RAF score for a community, non-dual, aged enrollee (published V28 weights range from 0.209 to 0.390 depending on the payment segment). A more severe related category (HCC 276, HCC 277, HCC 278, and HCC 279) supersedes it when both are reported. See the full factor table on the HCC 280 category page.
