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FY2027

ICD-10 Code for Down syndrome

The ICD-10-CM code for down syndrome is Q90.9Down syndrome, unspecified. This is the code the Alphabetic Index gives for down syndrome with no further qualifier, valid for FY2027 (October 1, 2026September 30, 2027).

BillableUnspecified

Q90.9 is billable but unspecified. If the documentation names a type, site or cause, one of the more specific codes below is likely expected.

Which down syndrome code should you use?

The Alphabetic Index lists 4 codes under Down syndrome. Which one applies depends on the qualifier documented in the record — the type, site, cause, or associated condition. Find the qualifier below, then verify the code in the Tabular List before using it.

By type

meiotic nondisjunctionQ90.0Trisomy 21, nonmosaicism (meiotic nondisjunction)
mitotic nondisjunctionQ90.1Trisomy 21, mosaicism (mitotic nondisjunction)
mosaicismQ90.1Trisomy 21, mosaicism (mitotic nondisjunction)
translocationQ90.2Trisomy 21, translocation

Index terms and codes are reproduced from the official ICD-10-CM FY2027 release. The Alphabetic Index is a finding aid — a code must always be verified in the Tabular List before it is reported. Data sources