2026 ICD-10-CM Diagnosis Code Q03Congenital hydrocephalus

ICD-10-CM Codes›Q00-Q99›Q00-Q07›Q03

ICD-10-CM Q03
CMSSource: CMS FY 2026 ICD-10-CM dataset · Effective Oct 1, 2025 – Sep 30, 2026

Q03 is a non-billable ICD-10-CM category code for congenital hydrocephalus, so it cannot be submitted on claims. Use a more specific code from this category instead, such as Q03.0, Q03.1, Q03.8, and Q03.9.

Code Identity

ICD-10-CM Code
Q03
Billable Status
No — Non-Billable Category
Code Describes
Congenital hydrocephalus
Chapter
Q00-Q07
Congenital malformations of the nervous system

Code Classification

ChapterQ00-Q99Congenital malformations, deformations and chromosomal abnormalities
SectionQ00-Q07Congenital malformations of the nervous system
CategoryQ03Congenital hydrocephalus
This CodeQ03Congenital hydrocephalus

Specific Coding for Congenital hydrocephalusOverview

Non-specific codes like Q03 require more characters. Use one of these billable codes instead:

  • Use Q03.0 for Malformations of aqueduct of Sylvius

  • Use Q03.1 for Atresia of foramina of Magendie and Luschka

  • Use Q03.8 for Other congenital hydrocephalus

  • Use Q03.9 for Congenital hydrocephalus, unspecified

Tabular List NotesGuidance

Coding notes and annotation back-references applicable to this code.

Includes

  • hydrocephalus in newborn

Type 1 Excludes

  • Arnold-Chiari syndrome, type II Q07.0
  • acquired hydrocephalus G91
  • hydrocephalus due to congenital toxoplasmosis P37.1
  • hydrocephalus with spina bifida Q05.0 Q05.4

Clinical InformationClinical

  • Congenital Hydrocephalus

    hydrocephalus that is present at birth.

Patient EducationClinical

Hydrocephalus

Hydrocephalus is the buildup of too much cerebrospinal fluid in the brain. Normally, this fluid cushions your brain. When you have too much, though, it puts harmful pressure on your brain.

Read the full article at MedlinePlus

Courtesy of MedlinePlus, a service of the U.S. National Library of Medicine.

Code HistoryHistory

FY 2016AddedAdded to the ICD-10-CM code setEffective October 1, 2015, the first year of ICD-10-CM.
FY 2017–2025No changes
FY 2026CurrentCurrent code set, no changesEffective October 1, 2025 through September 30, 2026.

Questions About Q03Overview

Is Q03 (Congenital hydrocephalus) a billable code?

No. This is a category header that groups the codes for congenital hydrocephalus, and headers cannot be submitted on claims. Claims for congenital hydrocephalus need a more specific code from this category, such as Q03.0, Q03.1, and Q03.8.