ICD-10 Code F91.3 – Oppositional defiant disorder (2026): Diagnosis, Symptoms & Billing Guide
2026 ICD-10-CM Diagnosis Code F91.3 – Oppositional defiant disorder
What it is
F91.3 identifies oppositional defiant disorder, a childhood behavioral disorder marked by a persistent pattern of angry, argumentative, or defiant behavior toward authority figures. Use it when documentation specifically names this diagnosis.
Clinical signs
Typical findings include frequent irritability, arguing with adults, refusing rules, and deliberate annoyance of others. Clinical features vary; refer to documentation.
When to use this code
Use F91.3 when the provider documents oppositional defiant disorder as the confirmed diagnosis. It may also fit when the record describes a chronic pattern of defiance and hostility consistent with that diagnosis. If the note is unclear, check documentation before coding.
Do not use for
Do not use this code for normal misbehavior, isolated anger, or vague “behavior problems” without a documented diagnosis. Check documentation if conduct disorder, ADHD, or another condition better explains the behavior.
Coding tip
Code F91.3 only when the diagnosis is clearly stated or well supported in the assessment.