ICD-10-CM 2027 diagnosis code
Q03Congenital hydrocephalus
Q03 is a header code, so it can't be reported by itself. Choose one of the 4 more specific codes beneath it.
Code unchanged since ICD-10-CM took effect on October 1, 2015. Source: official FY2027 ICD-10-CM release from CDC/NCHS and CMS. Page updated September 29, 2026. About our data
About Q03
Q03 is the ICD-10-CM diagnosis code for congenital hydrocephalus. It belongs to block Q00-Q07 (congenital malformations of the nervous system) and chapter 17 (congenital malformations, deformations, chromosomal abnormalities, and genetic disorders). It is a header code, so it can't be reported by itself; one of its 4 subcodes must be used instead.
To report this condition, pick the subcode that matches the documentation: Q03.0 (Sylvius), Q03.1 (Luschka), Q03.8 (hydrocephalus) and Q03.9 (unspecified).
Don't report Q03 together with the conditions in its Excludes1 note: Arnold-Chiari syndrome, type II (Q07.0-), acquired hydrocephalus (G91.-), hydrocephalus due to congenital toxoplasmosis (P37.1) and hydrocephalus with spina bifida (Q05.0-Q05.4).
It has been part of ICD-10-CM since the code set took effect on October 1, 2015 and hasn't changed since.
Specific codes under Q03
Coding notes
- hydrocephalus in newborn
Notes that apply from higher levels
Instructions written at a parent level also apply to Q03.
Broader instructions also apply from Chapter 17: Congenital malformations, deformations, chromosomal abnormalities, and genetic disorders.
Codes whose notes reference Q03
Code history
- 2016
- 2017
- 2018
- 2019
- 2020
- 2021
- 2022
- 2023
- 2024
- 2025
- 2026
- 2027
- FY2016 (effective 10/1/2015): Added (first year of ICD-10-CM)
- No changes since FY2016.
Common questions about Q03
Is Q03 billable?
- No. Q03 is a header code. Report one of its more specific subcodes instead.