Q21.3: Tetralogy of Fallot
Q21.3 is the billable ICD-10-CM diagnosis code for Tetralogy of Fallot. It is a fully specified code, so it can be reported on a claim (subject to clinical documentation and your payer's rules).
Frequently asked questions
What is ICD-10-CM code Q21.3?
Q21.3 is the ICD-10-CM diagnosis code for Tetralogy of Fallot. It belongs to category Q21 (Congenital malformations of cardiac septa).
Is Q21.3 a billable code?
Yes. Q21.3 is a billable, fully specified ICD-10-CM code, so it can be used on a claim (subject to documentation and payer rules).
What category does Q21.3 belong to?
Q21.3 is part of ICD-10-CM category Q21 — Congenital malformations of cardiac septa, which has 34 billable codes.
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Informational only, not coding or medical advice. Verify against the official ICD-10-CM (FY2026) and your payer's guidelines.
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