2026 ICD-10-CM Diagnosis Code J13Pneumonia due to Streptococcus pneumoniae
ICD-10-CM Codes›J00–J99›J09-J18›J13
- Billable — Valid for Submission
- MCC — Major Complication or Comorbidity
- Not Chronic
J13 is a billable ICD-10-CM diagnosis code for pneumonia due to Streptococcus pneumoniae. It is valid on HIPAA claims for fiscal year 2026 (October 1, 2025 through September 30, 2026) and groups to MS-DRG 193 through 195, 791, 793, 974 through 976. As a secondary diagnosis, it counts as a major complication or comorbidity (MCC) and places an inpatient stay in the highest severity level of its MS-DRG family. It does not count, however, when the principal diagnosis is one of 129 closely related codes. In AHRQ's Clinical Classifications Software (CCSR), this diagnosis falls under Bacterial infections and Pneumonia (except that caused by tuberculosis).
J13 no longer risk-adjusts for Medicare Advantage: it mapped to HCC 115 under the retired CMS-HCC V24 model through payment year 2025 but maps to no category in the live V28 model. It still risk-adjusts in the PACE (CMS-HCC V22) category 115, ESRD (V21) category 115, and ESRD (V24) category 115 for payment year 2026.
Code Identity
Code Classification
Medicare Risk Adjustment (HCC)Billing
J13 no longer risk-adjusts for Medicare Advantage: it maps to no payment category in the live CMS-HCC V28 model, although it still risk-adjusts in the other CMS models shown below.
Source: CMS Payment Year 2026 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.
- Bacterial pneumonia co-occurrent with human immunodeficiency virus infection
- Bacterial pneumonia with AIDS
- Bronchopneumonia caused by Streptococcus
- Bronchopneumonia caused by Streptococcus pneumoniae
- Disorder of respiratory system co-occurrent with human immunodeficiency virus infection
- Lobar pneumonia
- Pneumococcal bronchitis
- Pneumococcal lobar pneumonia
- Pneumococcal pneumonia
- Pneumococcal pneumonia with AIDS
- Pneumonia with AIDS
- Respiratory disorder with AIDS
Tabular List NotesGuidance
Coding notes and annotation back-references applicable to this code.
Inclusion Terms
- Bronchopneumonia due to S. pneumoniae
Code First
Code Also
Type 1 Excludes
- congenital pneumonia due to S. pneumoniae P23.6
- lobar pneumonia, unspecified organism J18.1
- pneumonia due to other streptococci J15.3 J15.4
These terms are the conditions for which that code is to be used. The terms may be synonyms of the code title, or, in the case of "other specified" codes, the terms are a list of the various conditions assigned to that code. The inclusion terms are not necessarily exhaustive. Additional terms found only in the Alphabetic Index may also be assigned to a code.
Certain conditions have both an underlying etiology and multiple body system manifestations due to the underlying etiology. For such conditions, the ICD-10-CM has a coding convention that requires the underlying condition be sequenced first followed by the manifestation. Wherever such a combination exists, there is a "use additional code" note at the etiology code, and a "code first" note at the manifestation code. These instructional notes indicate the proper sequencing order of the codes, etiology followed by manifestation.
A "code also" note instructs that two codes may be required to fully describe a condition, but this note does not provide sequencing direction.
A type 1 excludes note is a pure excludes note. It means "NOT CODED HERE!" An Excludes1 note indicates that the code excluded should never be used at the same time as the code above the Excludes1 note. An Excludes1 is used when two conditions cannot occur together, such as a congenital form versus an acquired form of the same condition.
Index to Diseases and InjuriesGuidance
Alphabetical index entries that point to this code.
Pneumonia (acute) (double) (migratory) (purulent) (septic) (unresolved) J18.9
Clinical ClassificationClinical
AHRQ’s CCSR groups this code into broader clinical categories.
Clinical InformationClinical
Pneumococcal Pneumonia
pneumonia that is attributed to the bacteria streptococcus pneumonia.
Patient EducationClinical
Pneumococcal Infections
Pneumococci are a type of streptococcus bacteria. The bacteria spread through contact with people who are ill or by healthy people who carry the bacteria in the back of their nose. Pneumococcal infections can be mild or severe. The most common types of infections are:
Read the full article at MedlinePlus
Courtesy of MedlinePlus, a service of the U.S. National Library of Medicine.
Convert J13 to ICD-9-CMHistory
The closest ICD-9-CM equivalents under the General Equivalence Mappings.
Code HistoryHistory
Questions About J13Overview
What is the ICD-10 code for pneumonia due to Streptococcus pneumoniae?
The ICD-10-CM code for pneumonia due to Streptococcus pneumoniae is J13. It is billable on HIPAA-covered claims from October 1, 2025 through September 30, 2026.
Is J13 (Pneumonia due to Streptococcus pneumoniae) a billable code?
Yes. This is a billable ICD-10-CM code, specific enough to report pneumonia due to Streptococcus pneumoniae on HIPAA-covered claims from October 1, 2025 through September 30, 2026.
What MS-DRG does J13 group to?
When pneumonia due to Streptococcus pneumoniae is the principal diagnosis on an inpatient stay, it groups to MS-DRG 193, 194, 195, 791, 793, 974, 975, 976, with relative weights from 0.6285 to 4.1696 depending on complications. Higher weights mean higher Medicare reimbursement.
Is J13 a CC or MCC?
CMS lists J13 as an MCC (major complication or comorbidity) for FY 2026. Reported as a secondary diagnosis, it places the inpatient stay in the highest-weighted DRG of its severity family. It does not count when the principal diagnosis is one of the 129 closely related codes in its exclusion list.
What is the ICD-9 equivalent of J13?
Under the General Equivalence Mappings, pneumonia due to Streptococcus pneumoniae converts to ICD-9-CM 481 (pneumococcal pneumonia). The mapping is approximate, so confirm the match fits the documentation.
Does J13 risk-adjust for Medicare Advantage payment?
Not for Medicare Advantage. J13 mapped to HCC 115 in the retired CMS-HCC V24 model, which last determined payment in 2025, but it maps to no category in the live V28 model; see all codes that no longer risk-adjust. It still risk-adjusts in the PACE (CMS-HCC V22) category 115 (Pneumococcal Pneumonia/Empyema/Lung Abscess), ESRD (V21) category 115 (Pneumococcal Pneumonia/Empyema/Lung Abscess), and ESRD (V24) category 115 (Pneumococcal Pneumonia/Empyema/Lung Abscess).
