ICD-10-CM 2027 diagnosis code

Q90Down syndrome

Not billable — use a more specific code

Q90 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 Q90

Q90 is the ICD-10-CM diagnosis code for down syndrome. It belongs to block Q90-Q99 (chromosomal abnormalities, not elsewhere classified) 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: Q90.0 (nondisjunction)), Q90.1 (nondisjunction)), Q90.2 (translocation) and Q90.9 (unspecified).

Use an additional code(s) to identify any associated degree of intellectual disabilities (F70-F79).

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 Q90

Coding notes

Use additional codeAdd a secondary code to fully describe the condition

code(s) to identify any associated degree of intellectual disabilities (F70-F79)

Code alsoTwo codes may be needed; sequencing depends on circumstances

associated physical condition(s), such as atrioventricular septal defect (Q21.2-)

Notes that apply from higher levels

Instructions written at a parent level also apply to Q90.

Broader instructions also apply from Q90-Q99 Chromosomal abnormalities, not elsewhere classified and Chapter 17: Congenital malformations, deformations, chromosomal abnormalities, and genetic disorders.

Codes whose notes reference Q90

D84.81Code first
E25Excludes1
Q92Excludes1
Z15Excludes1

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 Q90

Is Q90 billable?: No. Q90 is a header code. Report one of its more specific subcodes instead.