ICD-10 Code F21 – Schizotypal disorder (2026): Diagnosis, Symptoms & Billing Guide
2026 ICD-10-CM Diagnosis Code F21 – Schizotypal disorder
What it is
F21 identifies schizotypal disorder, a condition marked by persistent odd beliefs, eccentric behavior, and social discomfort. Use it when documentation describes a schizotypal pattern rather than a primary psychotic episode.
Clinical signs
Typical features include unusual thinking, suspiciousness, odd speech, and limited close relationships. Clinical features vary; refer to documentation when the record does not clearly describe the pattern.
When to use this code
Use F21 when the provider documents schizotypal disorder or schizotypal personality disorder. It also fits records describing longstanding eccentricity, social isolation, and cognitive or perceptual distortions without meeting criteria for another psychotic disorder.
Do not use for
Do not use this code for schizophrenia, delusional disorder, or transient psychotic symptoms unless the record specifically supports schizotypal disorder. Check documentation if the diagnosis is unclear.
Coding tip
Code from the provider’s exact diagnosis wording and confirm whether the condition is described as schizotypal disorder or a different psychotic-spectrum diagnosis.