ICD-10-CM 2027
ICD-10 code for neonatal pneumonia
From the official ICD-10-CM alphabetic index entry “Pneumonia (acute) (double) (migratory) (purulent) (septic) (unresolved) › neonatal”. Page updated September 29, 2026.
About coding neonatal pneumonia
The ICD-10-CM code for neonatal pneumonia is P23.9 (Congenital pneumonia, unspecified).
Within P23, choose P23.9 (unspecified) only when documentation doesn't support a more specific option: due to viral agent (P23.0), due to Chlamydia (P23.1), due to staphylococcus (P23.2), due to streptococcus, group B (P23.3), due to Escherichia coli (P23.4), due to Pseudomonas (P23.5), due to other bacterial agents (P23.6) and due to other organisms (P23.8).
As a secondary diagnosis it is an MCC (major complication or comorbidity), which can move an inpatient stay into the highest-paying "with MCC" MS-DRG of its family, unless the principal diagnosis excludes it.
In MS-DRG v44.0, it is part of the grouping logic for DRG 791 (Prematurity with Major Problems, relative weight 4.1075) and DRG 793 (Full Term Neonate with Major Problems, relative weight 4.2195), in MDC 15 (Newborns and Other Neonates with Conditions Originating in the Perinatal Period), as a principal or secondary diagnosis. The DRG a claim lands in depends on the principal diagnosis, procedures and any CC/MCC secondary diagnoses.
More specific neonatal pneumonia codes (official index)
- aspiration
Common questions about neonatal pneumonia ICD-10 codes
What is the ICD-10 code for neonatal pneumonia?
- P23.9 — Congenital pneumonia, unspecified.
Is P23.9 billable?
- Yes. P23.9 is a billable/specific ICD-10-CM code valid for FY2027 (October 1, 2026 – September 30, 2027).
Can P23.9 be used as a principal diagnosis?
- Yes. The Medicare Code Editor doesn't restrict P23.9 as a principal diagnosis.
Is P23.9 a CC or MCC?
- P23.9 is an MCC (major complication or comorbidity) under MS-DRG v44.0, unless excluded by the principal diagnosis.