ICD-10 J42
Billable / Specific HCC v28: 111Unspecified chronic bronchitis
About ICD-10-CM J42
ICD-10-CM code J42 represents Unspecified chronic bronchitis. This is a billable/specific code in the Respiratory System chapter (block J42). The 2026 edition of ICD-10-CM J42 became effective on October 1, 2025.
Coding Tips for J42
Specialist guidance from the PayerReady Medical Coding Team. Specificity warnings, HCC capture rules, sequencing notes.
J42 is a CMS-HCC v28 risk-adjustment code (category 111). To count for the patient Risk Adjustment Factor (RAF), document the diagnosis with MEAT language each calendar year: Monitored, Evaluated, Assessed, Treated. A diagnosis on the problem list alone does not satisfy CMS RADV audit standards. Include the diagnosis in the assessment with current status and current treatment plan.
Inclusion Terms / Approximate Synonyms
Clinical terms and conditions classified under J42. Per CMS ICD-10-CM Tabular 2026.
- Chronic bronchitis NOS
- Chronic tracheitis
- Chronic tracheobronchitis
Type 1 Excludes
Pure excludes, these codes can never be coded together with J42. The conditions are mutually exclusive (e.g., congenital vs acquired forms).
- bronchiolitis obliterans and bronchiolitis obliterans syndrome (J44.81)
- chronic asthmatic bronchitis (J44.-)
- chronic bronchitis with airways obstruction (J44.-)
- chronic emphysematous bronchitis (J44.-)
- chronic obstructive pulmonary disease NOS (J44.9)
- simple and mucopurulent chronic bronchitis (J41.-)
Use Additional Code
When coding J42, also report these additional codes when applicable.
- 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.-)
- tobacco use (Z72.0)
Medicare Advantage HCC Impact
Capture this diagnosis annually for accurate risk adjustment. Missed HCC captures are the #1 revenue leak in Medicare Advantage risk programs.
Medicare LCD Coverage for J42
Local Coverage Determinations (LCDs) from CMS MACs that list J42 as a covered diagnosis.
Showing top 10 of 365 total . Click a CPT for full coverage scope.
Commercial Payer Coverage
Coverage policies from major commercial payers referencing J42.
2 Aetna
5 Medicare
CPT Codes Commonly Billed with J42
Procedures frequently paired with this diagnosis based on PayerReady's Dx↔Px linkage data.
- 94620 Pulmonary function testing for respiratory symptoms Internal Medicine
Convert J42 to ICD-9-CM
Per CMS General Equivalence Mappings (GEMs), useful for legacy data review and historical claim analysis.
| ICD-10 | ICD-9 | Mapping Flags |
|---|---|---|
| J42 | 4919 | 00000 |
Flags format (5 digits): Approximate · No Map · Combination · Scenario · Choice List. Source: CMS 2017 GEMs (final version).
Codes Adjacent To J42
Other codes in section J40-J4A (Chronic lower respiratory diseases).
ICD-10 J42, Billing FAQ
Is ICD-10 code J42 billable? +
Yes, J42 is a billable ICD-10-CM code that can appear as a primary or secondary diagnosis on claims.
What other names or terms map to J42? +
ICD-10 J42 includes: Chronic bronchitis NOS; Chronic tracheitis; Chronic tracheobronchitis.
What codes are Type 1 Excludes for J42? +
Type 1 Excludes (never code together with J42): bronchiolitis obliterans and bronchiolitis obliterans syndrome (J44.81); chronic asthmatic bronchitis (J44.-); chronic bronchitis with airways obstruction (J44.-)
Does J42 affect Medicare Advantage HCC risk adjustment? +
Yes. J42 maps to CMS-HCC v28 category 111. Capture this diagnosis annually for accurate Medicare Advantage risk score.
What CPT codes are commonly billed with J42? +
Procedures frequently paired with J42 include: 94620.
What ICD-9 codes does J42 map to? +
Per CMS GEMs, J42 maps to ICD-9 codes: 4919. Useful for legacy data review and historical claim analysis.
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Reviewed by the PayerReady Medical Coding Team
Verified against the CMS 2026 code set on July 17, 2026.
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