Q21.1
⚠ Non-billable
Atrial septal defect
ICD-10-CM · FY2026 · Congenital Malformations, Deformations and Chromosomal Abnormalities
Code
Q21.1
System
ICD-10-CM
Billable
No — use specific code
Effective
FY2026
Chapter
Congenital Malformations, Deformations and Chromosomal Abnormalities
Source
CMS / CDC NCHS
⚠ Verify before billing. Confirm against the current CMS/NCHS ICD-10-CM files and your payer's rules before claims submission.
Frequently asked questions
What is ICD-10 code Q21.1?
ICD-10-CM code Q21.1 represents Atrial septal defect. It is a non-billable header code requiring a more specific subcategory in the Congenital Malformations, Deformations and Chromosomal Abnormalities chapter, effective October 1, 2025 – September 30, 2026.
Is Q21.1 billable?
No. Q21.1 is a non-billable header. Select a more specific subcategory for claims submission.
What chapter is Q21.1 in?
Q21.1 belongs to the Congenital Malformations, Deformations and Chromosomal Abnormalities chapter (Q00–Q99) of ICD-10-CM.
Related codes in the Q21 category
Q21
Congenital malformations of cardiac septa
Non-billable
Q21.0
Ventricular septal defect
Billable
Q21.2
Atrioventricular septal defect
Non-billable
Q21.3
Tetralogy of Fallot
Billable
Q21.4
Aortopulmonary septal defect
Billable
Q21.8
Other congenital malformations of cardiac septa
Billable
Q21.9
Congenital malformation of cardiac septum, unspecified
Billable
Q21.10
Atrial septal defect, unspecified
Billable
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